Inside the Vara 2 Plus

Installation &
Operating Instructions
Inside the Vara 2 Plus
Engineering Specifications
Vertical
Forced Air
EV 38 thru 68 Series
Vara 2 Plus Vertical Unit
Air Filter
Air Coil
Transformer
Intelligent
5/10 kW
Electric
Elements
Variable
Speed
ECM
Blower
Contactor
Controller
Reversing
Valve
Thermostatic
Expansion Valve
Two-Step
Scroll
Compressor
Desuperheater
(Optional)
Air Pad
Key to Model Numbers
Legend for Tables
BTU/hr
CAP
COP
CFM
DB
DHW
DWR
dP
EER
EWT
FLA
GND
GPM
Heating or cooling capacity
Capacity
Coefficient of performance (BTU/hr out  BTU/hr in)
Cubic feet per minute
Dry-bulb entering air temperature
Domestic hot water
Domestic hot water, extra capacity
Pressure drop across heat pump (in feet of water and psi)
Energy efficiency ratio (BTU/hr CAP  watts in)
Entering water temperature (in degrees Fahrenheit)
Full-load amperage
Ground
Gallons per minute of water flow
HE
HR
HYD
KW
LRA
MBTU/hr
RLA
SR
SUP
VA
WB
Heat extracted
Heat rejected
Hydronic
Kilowatt input
Locked-rotor amperage
Btu/hr X 1000
Rated-load amperage
Sensible Ratio (sensible cooling capacity 
total cooling capacity)
Supplemental domestic water heating
Volt-amperes
Wet-bulb entering air temperature
All Pressure Drop Ratings are for Pure Water.
See last page for Correction Factors.
Performance values are +/- 10%, and are subject to change without notice.
TABLE OF CONTENTS
Section
Title
I.
II.
Introduction to ECONAR Heat Pumps
Vara 2 Plus Features
A. Two-Step Compressor Operation
B. Variable Speed ECM Blower
C. Intelligent Electric Resistance Elements
D. R-410a Refrigerant
Unit Sizing
A. Building Heat Loss / Heat Gain
B. Ground Sources & Design Water Temperatures
1. Ground Loop Applications
2. Ground Water Applications
C. Temperature Limitations
Unit Location / Mounting
Condensate Drain
Duct System / Blower
Ground Source Design
A. Ground Loop Installation
B. Ground Water Installation
1. Ground Water Freeze Protection Switch
2. Water Coil Maintenance
Electrical Service
24 Volt Control Circuit
A. Transformer
B. Thermostat
C. Controller
Startup / Checkout
Service
A. Air Filter
B. Lockout Lights
C. Preseason Inspection
Room Thermostat Operation
Desuperheater (Optional)
Performance Ratings Configuration Options
Performance Data
Fan Performance & Physical Data
Unit Dimensions
Electrical & Correctional Factors
Pressure Drop Ratings
Wiring Diagrams
Troubleshooting Guide for Lockout Conditions
Troubleshooting Guide for Unit Operation
Troubleshooting Guide for ECM Blower
Additional Figures
III.
IV.
V.
VI.
VII.
VIII.
IX.
X.
XI.
XII.
XIII.
XIV.
XV.
XVI.
XVII.
XVIII.
XIX.
XX.
XXI.
XXII.
XXIII.
XXIV.
Page
2
2
3
4
5
5
6
9
9
11
12
13
13
15
16
19
19
20
21
22
23
24
26
27
1
I.
INTRODUCTION TO ECONAR
HEAT PUMPS
personnel should install, repair or service. The installer is
responsible to ensure that all local electrical, plumbing,
heating and air conditioning codes are followed.
Enertech Global, LLC, is home to ECONAR geothermal
heat pumps, a brand that has been in Minnesota for over
twenty years. The cold winter climate has driven the
design of ECONAR’s heating and cooling equipment to
what is known as a "ColdClimate" geothermal heat pump.
This cold climate technology focuses on maximizing the
energy savings available in heating dominated regions
without sacrificing comfort. Extremely efficient heating,
cooling, dehumidification and optional domestic hot
water heating are provided in one neatly packaged
system.
WARNING – ELECTRICAL SHOCK CAN CAUSE
Enertech produces three types of ECONAR heat pumps:
hydronic, which transfers energy from water to water;
forced air, which transfers energy from water to air; and
combination, which incorporates the hydronic heating
unit into a forced air unit. Geothermal heat pumps get
their name from the transfer of energy to and from the
ground. The ground-coupled heat exchanger (geothermal
loop) supplies the source energy for heating and absorbs
the discharged energy from cooling. The system uses a
compression cycle, much like your refrigerator, to collect
the ground’s energy supplied by the sun and uses it to
heat your home. Since the process only moves energy,
and does not create it, the efficiencies are three to four
times higher than most efficient fossil fuel systems.
CAUTION – Ground loops must be freeze protected.
Insufficient amounts of antifreeze may cause severe
damage and may void warranty. Never operate with
ground loop flow rates less than specified. Continuous
operation at low flow rates, or no flow, may cause severe
damage and may void warranty.
Safety and comfort are designed into every ECONAR
geothermal heat pump. Since the system runs completely
on electrical energy, the entire home can have the safety
of being gas-free. The best engineering and quality
control is in every heat pump. Proper application and
correct installation will ensure excellent performance and
customer satisfaction. The Enertech commitment to
quality is written on the side of every heat pump built.
Throughout the manufacturing process, the technicians
who assemble each unit sign their names to the quality
assurance label after completing their inspections. As a
final quality test, every unit goes through a full run-test
where the performance and operation is verified in both
the heating and cooling modes. No other manufacturer
goes as far as to run a full performance check to ensure
system quality.
This guide discusses the Vara 2 Plus series heat pumps
that are equipped with a two-step scroll compressor, a
variable speed ECM blower motor, and electric resistance
elements to provide varying capacities of heating and
cooling within the same unit. These heat pumps also
utilize R-410A, an HFC refrigerant, which is
environmentally friendly to earth’s protective ozone layer.
WARNING – Service of refrigerant- based equipment
can be hazardous due to elevated system pressures and
hazardous voltages. Only trained and qualified service
2
PERSONAL INJURY OR DEATH. Disconnect all
power supplies before installing or servicing electrical
devices. Only trained and qualified service personnel
should install, repair or service this equipment.
WARNING – Verify refrigerant type before servicing.
The nameplate on the heat pump identifies the type and
the amount of refrigerant. All refrigerant removed from
these units must be reclaimed by following accepted
industry and agency procedures.
CAUTION – R410A refrigerant requires extra
precaution when service work is being performed. The
operating pressures are approximately 150% higher than
R-22 – which can cause personal injury. Invasion into
the refrigerant system must be a last resort. Ensure all
other diagnosis and methods have been used before
attaching refrigerant instruments and before opening the
refrigerant system. Synthetic oil (POE) is extremely
hydroscopic, meaning it has a strong chemical attraction
to moisture. Brief exposure to ambient air could cause
POE to absorb enough moisture that a typical vacuum
may not remove.
COMMON ACRONYMS
CFM
DHW
dP
EAT
ECM
EWT
GPM/gpm
Ground Loop
Ground Water
GTF
HP
kW
LP
P/T
VA
Cubic Feet per Minute
Domestic Hot Water
Pressure Differential
Entering Air Temperature
Electronically Commutated Motor
Entering Water Temperature
Gallons per Minute
Also known as Closed Loop
Also known as Open Loop
GeoThermal Transfer Fluid
High Pressure
Kilowatts
Low Pressure
Pressure/Temperature
Volt Amperes
II.Vara 2 Plus Features
The Vara 2 Plus is one of Enertechs’ most advanced
ECONAR geothermal heat pumps offering unique and
innovative features to optimize efficiency, comfort and
reliability of a home space conditioning system.
The Vara 2 Plus is a 3-Heat/2-Cool unit, which uses a
two-step modulating compressor to provide forced air
heating and cooling of the living space. This unit is
available with or without a factory-installed
desuperheater, which provides supplemental domestic hot
water heating. This option can typically supply up to 65%
of a home’s hot water needs throughout the year.
A. Two-Step Compressor Operation
The Vara 2 Plus heat pump uses a Copeland Scroll twostep compressor. This compressor has the ability to be run
at full-load operation, which provides 100% capacity, or it
can be run at part-load operation, which provides
approximately 75% of full-load capacity. This technology
provides these very important operating features:
1) The ability to run at part-load capacity, which will
handle the majority of a home’s heating and
cooling needs, while providing much more
energy-efficient operation.
2) Extended runtimes without interruptions to
maintain the highest comfort possible.
3) High heating output and moderate cooling output
with staged capacity to precisely fit the heating
and cooling loads of homes in cold climates.
B. Variable Speed ECM Blower
A variable speed blower motor is used on the Vara 2 Plus
series heat pump to keep the three-stage operation of the
system operating comfortably, with very low electrical
usage. The Electronically Commutated Motor (ECM)
converts 230 Volt AC power to DC power internally. The
DC power is then modulated to turn the motor at a variety
of speeds.
The room thermostat determines the blower’s speed. If
the thermostat is calling for only the FAN to operate, the
blower will deliver a low amount of airflow in cubic feet
per minute (CFM). This low CFM gently circulates air
throughout the house, eliminating hot or cold spots, and
actually reduces the need for mechanical heating or
cooling at certain times of the year.
When the thermostat calls for first stage heating or
cooling, the blower speed will increase to its medium-low
speed setting. When the thermostat calls for second stage
heating or cooling, the blower increases to medium-high
speed. If third stage heating or Emergency Heat is calling,
the blower will run at its high speed setting. The air coil
has a minimum CFM requirement to operate properly
based on stage of operation in which the unit is running.
With first stage heating or cooling running, the mediumlow speed setting must supply enough airflow. With
second stage running, the medium-high speed setting is
required. The blower speeds of the Vara 2 Plus heat
pumps are factory-set to provide the highest efficiency at
each stage of operation.
The blower is also programmed to provide soft starting to
reduce air noise, delays after compressor shutdown to
distribute all the heat output from the compressor to the
heated space, and ramped speed changes. All these
features are designed for quiet, comfortable, efficient
operation.
C. Intelligent Electric Resistance
Elements
The Vara 2 Plus vertical top discharge units are equipped
with factory-installed electric resistance elements. These
elements provide an extra five kilowatts (approximately
17,000 BTU/hr) of supplemental heat when the room
thermostat calls for auxiliary heat. They also provide 10
kilowatts (approximately 34,000 BTU/hr) of backup heat
when the room thermostat is set to the emergency heat
mode. The heater can also be wired to supply the full
10kW during either supplemental or emergency heat
modes.
In order to provide greater comfort, the third stage signal
will “latch” to the second stage call from the thermostat.
This will allow the elements to run until second stage of
the thermostat is satisfied, causing the room temperature
to be closer to the thermostat setpoint.
Also, on units equipped with a desuperheater, a third
stage call will de-energize the desuperheater pump. This
allows the full capacity of the heat pump to be used to
heat the living space.
The Vara 2 Plus Horizontal and Bottom Discharge units
do not have factory installed internal electric elements.
D. R-410a Refrigerant
The Vara 2 Plus utilizes R-410A refrigerant. R-410a is a
zero-ozone depleting refrigerant, making the Vara 2 Plus
even more Earth friendly.
CAUTION – R-410A refrigerant has approximately
150% higher operating pressures than R-22 and requires
extra precaution during servicing. Also, never leave the
refrigerant system open to atmosphere longer than
absolutely necessary, because of the hydroscopic
properties of the refrigerant oil.
III. UNIT SIZING
Selecting the unit capacity of a forced air geothermal heat
pump requires three things:
A) Building Heat Loss/Heat Gain.
B) Ground Sources and Design Water Temperatures.
C) Temperature Limitations.
A. Building Heat Loss/Heat Gain
3
The space load must be estimated accurately for any
successful HVAC installation. There are many guides or
computer programs available for load estimation
including the Geothermal Heat Pump Handbook, Manual
J, and others. After the heat loss and heat gain analysis is
completed and loop EWT are established, the heat pump
can now be selected using forced air heat pump data in
the Engineering Specifications. Choose the capacity of the
heat pump based on both heating and cooling loads.
B. Ground-Sources and Design Water
Temperatures
Ground sources include the Ground Water (typically a
well) and the Ground Loop varieties. Water flow-rate
requirements vary based on configuration. ECONAR
Engineering Specifications provide capacities at different
loop water temperatures. Note: Table 1 shows the waterflow (GPM) requirements and water-flow pressure
differential (dP) for the heat exchanger, and Table 2
shows the dP multiplier for various levels of freeze
protection.
Table 1 – Groundside Flow Rate Requirements
Ground Loop
50oF Ground Water
Flow
dP*
Flow
dP*
(gpm)
(psig)
(gpm)
(psig)
9
3.1
6
1.6
GV38
12
5.3
7
2.4
GV48
15
4.9
10
3.0
GV58
* dP (psig) heat exchanger pressure drops are for pure water.
Note: dP values are for standard heat exchanger configurations. Cupro
Nickel heat exchanger configurations for Ground Water applications
have higher dP.
Series
Table 2 – Heat Exchanger Pressure Differential (dP)
Correction Factors for Freeze Protection (Typical)
AntiFreeze
(1)
Percent
Volume
Freeze
Level
dP Multiplier
25oF
35oF
90oF
110oF
o
GTF
50% GTF
12 F
125% 123% N/a
N/a
Propylene
20%
18oF
136% 133% 118% 114%
Glycol
25%
15oF
145% 142% N/a
N/a
(1) GTF = GeoThermal Transfer Fluid. 60% water, 40%
methanol.
1. Ground Loop Systems
Loop systems use a high-density polyethylene pipe buried
underground to supply a tempered water solution back to
the heat pump. Ground loops operate at higher flow rates
than ground water systems because the entering water
temperature (EWT) is lower. EWT affects the capacity of
the unit in the heating mode, and loops in cold climates
are normally sized to supply wintertime EWT to the heat
pump down to 25oF.
When selecting the heat pump, choose a unit that will
supply the necessary heating or cooling capacity at the
minimum and maximum ground loop EWT conditions
respectively. Example; if a residential system requires
45,000 Btu/hr to heat a house on an earth loop system
(designed for 32oF minimum wintertime EWT), and
40,000 Btu/hr to cool the house on an earth loop
4
(designed for 77oF summertime EWT), a GV48 Vara
Plus heat pump is required.
2
2. Ground Water Systems
Note: If a heat pump is installed with ground water, it
should have a Cupro-Nickel water coil (GVxxx-x-V02N).
Cupro-Nickel coils withstand well water much better than
standard water coils.
The design water temperature will be the well water
temperature in your geographic region for ground water
systems. Typical well water temperatures are in the 50 oF
range in many cold climates. If well water temperatures
are lower than 50oF (Canadian well water can be as low as
40oF) the flow rate must be increased to avoid leaving
water temperatures below the freezing point. If well water
temperatures are above 50oF (Some southern states are
above 70oF) the flow rates may need to be increased to
dump heat more efficiently in the cooling mode.
Varying well water temperatures will have little effect on
unit capacity in the cooling mode (since the well is
connected to the heat pump condenser), but can have
large effects on the capacity in the heating mode (since
the well is connected to the evaporator). If well water
temperatures are to exceed 70oF, special considerations,
such as ground loop systems, should be considered.
C. Temperature Limitations
Be aware of the operating range of the geothermal system
when sizing the particular heat pump to avoid premature
equipment failure. Operating outside of these limitations
may cause severe damage to the equipment and may void
warranty.
CAUTIONS:
–The acceptable Ground Loop EWT is 15oF to 70oF for
heating and 40oF to 95oF for cooling.
–The acceptable Ground Water EWT is 45oF minimum in
heating and 70oF maximum in cooling.
IV. UNIT LOCATION /
MOUNTING
CAUTION – Units must be kept in an upright position
during transportation or installation, or severe internal
damage may occur.
Important – To ensure easy removal and replacement
of access panels, leave panels secured in place until the
unit is set in place and leveled.
Important – Locate the unit in an indoor area where
the ambient temperature will remain above 45 oF. Service
is done primarily from the front. Top and rear access is
desirable and should be provided when possible.
Important – A field installed drain pan is required
under the entire unit where accidental water discharge
could damage surrounding floors, walls or ceilings.
CAUTION – Do not use this unit during construction.
Dust and debris may quickly contaminate electrical and
mechanical components; resulting in damage.
CAUTION – Before driving screws into the cabinet,
check on the inside of the unit to ensure the screw will not
damage electrical, water, or refrigeration lines.
Important – Units must be mounted on a vibrationabsorbing pad slightly larger than the base to provide
isolation between the unit and the floor. Water supply
pumps should not be hard plumbed directly to the unit
with copper pipe; this could transfer vibration from the
water pump to the refrigeration circuit, causing a
resonating sound. Hard plumbing must be isolated from
building structures that could also transfer vibration noise
from the unit through the piping to the living space.
CAUTION – Always use plastic male fittings into
plastic female or into metal female fittings. Never use
metal male fittings into plastic female fittings. On metalto-metal fittings; use pipe thread compound, do not use
pipe thread tape, hand tighten first, and then only tighten
an additional ½ turn with a tool if necessary. On plastic
fittings, always use 2 to 3 wraps of pipe thread tape, do
not use pipe thread compound, hand tighten first, and then
only tighten an additional ½ turn with a tool if necessary.
Do not over-tighten, or damage may occur.
V. CONDENSATE DRAIN
Condensate traps are built into every Vara 2 Plus Vertical
Top Discharge unit, so an external trap should not be
installed.
Important – Vertical units must be installed level to
ensure proper condensate drainage.
CAUTION – Horizontal units require an external
condensate trap in order to drain water from the heat
pump and must also be mounted level in order for the
condensate to drain.
CAUTION – Bottom Discharge (downflow) units have
two ½” MPT drains; one for the condensate, and one for
the cabinet. Each drain requires a separate external ¾”
condensate-vented trap, and the unit must be elevated
enough to provide clearance for the drain traps.
The condensate line leaving the U bend of the condensate
trap must be at least 3” below the base of the heat pump.
This requires the U bend to be 6” below the unit to give
the upward portion of the U bend a 3” lift. The condensate
trap should be vented after the U bend. The condensate
line should be pitched away from the unit a minimum of
1/8” per foot. If the unit produces an odor in the cooling
mode, the condensate trap or line may be plugged, or the
unit may not be pitched correctly. Bleach may be poured
down the condensate drain in the heat pump to kill any
bacterial growth in the condensate line.
Vented condensate traps are necessary to break the
negative pressure in the air chamber and allow the
condensate to flow. Construct condensate traps to the
following diagram.
Heat Pump
Base
Heat Pump
Base
Air Vent
6" drop
minimum
3" Rise
To drain
with 1/8"
per foot
minimum
pitch
Horizontal Units
Air Vent
6" drop
minimum
3" Rise
Bottom Discharge
Figure 1 – Condensate Drain - Horizontal and Bottom
Discharge Units Only
VI. DUCT SYSTEM/BLOWER
For the duct system, metal ductwork should be used, and
flexible connectors are required for discharge and return
air duct connections. An air inlet collar is provided on all
Vara 2 Plus units to facilitate duct connections. For
acceptable duct sizes, see Table 3.
If the duct system is installed in an uninsulated space, the
metal ductwork should be insulated on the outside to
prevent heat loss, absorb noise, and prevent condensation
from collecting on the ductwork.
Important – If the unit is connected to existing
ductwork, the ductwork must have the capacity to handle
the air volume required by the heat pump. Undersized
ductwork will cause noisy operation due to high air
velocity, and poor operating efficiencies.
The Vara 2 Plus heat pump uses a variable speed ECM
blower motor. The controller provides a total of 16 blower
speed set points. There are four different CFM outputs in
each of the four blower speed ranges (Low, MediumLow, Medium-High, and High). The settings and CFM
outputs are shown in Table 4.
Important – The blower will not operate properly if
ductwork is not attached. The ductwork supplies static
pressure to give the blower motor a load to work against.
The blower compartment access door must also be on for
the unit to run properly. Blower motors may overheat
without a load if run for an extended period of time.
Note – If problems occur, refer to the ECM Blower
Motor Troubleshooting Guide near the back of this
manual (Section XVI).
5
Table 3 - Duct Sizing Chart
CFM
Acceptable Branch Duct Sizes
Round
Rectangular
Acceptable Main or Trunk Duct Sizes
Round
Rectangular
4”
4x4
50
5”
4x5, 4x6
75
6”
4x8, 4x6
100
7”
4x10, 5x8, 6x6
150
8”
5x10, 6x8, 4x14, 7x7
200
9”
6x10, 8x8, 4x16
250
10”
6x14, 8x10, 7x12
300
10”
6x20, 6x16, 9x10
350
12”
6x18, 10x10, 9x12
10”
4x20, 7x10, 6x12, 8x9
400
12”
6x20, 8x14, 9x12, 10x11
10”
5x20, 6x16, 9x10, 8x12
450
10”
10x10, 6x18, 8x12, 7x14
500
12”
6x20, 7x18, 8x16, 10x12
600
12”
8x18, 9x15, 10x14, 12x12
800
14”
10x18, 12x14, 8x24
1000
16”
10x20, 12x18, 14x15
1200
16”
10x25, 12x20, 14x18, 15x16
1400
18”
10x30, 15x18, 14x20
1600
20”
10x35, 15x20, 16x19, 12x30, 14x25
1800
20”
10x40, 12x30, 15x25, 18x20
2000
Tables calculated for 0.05 to 0.10 inches of water friction per 100’ of duct. At these duct design conditions, along with the pressure drop through the filter,
the total design external static pressure is 0.20 inches of water.
Table 4 – Blower Speed Settings
TAP
B (58 Series)
C (48 Series)
D (38 Series)
Low (G)
815
740
520
Medium-Low (Y)
1425
1295
910
Medium-High (Y2)
1850
1680
1180
High (W2/E)
1920
1800
1300
Note: Adjust Tap set to “+” will increase these numbers by 10%
Adjust Tap set to “-” will decrease these numbers by 10%
VII. GROUND SOURCE
DESIGN
Since water is the source of energy in the wintertime and
the energy sinks in the summertime, good water supply is
possibly the most important requirement of a geothermal
heat pump system installation.
A. Ground Loop Installation
In a Ground Loop system the same water/antifreeze
solution is circulated through a closed system of highdensity polyethylene pipe buried underground. As the
solution passes through the pipe, it collects energy (in the
heating mode) that is being transferred from the relatively
warm surrounding soil through the pipe and into the
relatively cold solution. The solution is circulated to the
heat pump, which transfers energy out of the solution, and
then the solution circulates back through the ground to
extract more energy.
The Vara 2 Plus is designed to operate on either vertical
or horizontal ground loop applications. Vertical loops are
typically installed with a well drilling rig up to 200 feet
deep, or more. Horizontal loops are installed with
excavating or trenching equipment to a depth of about six
to eight feet deep, depending on geographic location and
length of pipe used. Earth Loops must be sized properly
6
for each particular geographic area, soil type, and
individual capacity requirements. Contact your local
installer or the Enertech Customer Support Line for help
with loop sizing requirements in your area.
Typical winter operating EWT to the heat pump ranges
from 25oF to 32oF.
CAUTION – Ground Loops must be properly freeze
protected. Insufficient amounts of antifreeze may result in a
freeze rupture of the unit or can cause unit shutdown
problems during cold weather operation. Propylene glycol
and Geothermal Transfer Fluid (GTF) are common
antifreeze solutions. GTF is methanol-based antifreeze and
should be mixed 50% with water to achieve freeze protection
of 12oF. Propylene glycol antifreeze solution should be
mixed 25% with water to obtain a 15oF freeze protection.
Important – Do not mix more than 25% propylene
glycol with water in an attempt to achieve a lower than
15oF freeze protection, since more concentrated mixtures
of propylene glycol become too viscous at low
temperatures and cannot be pumped through the earth
loop. Horizontal loops typically use GTF, and vertical
loops typically use propylene glycol. Note – Always
check state and local codes for any special requirements
on antifreeze solutions.
Flow rate requirements for ground loops are higher (see
Table 1) than ground water systems because water
temperatures are generally lower.
CAUTION – Never operate with flow rates less than
specified. Low flow rates, or no flow, may cause the unit
to shut down on a pressure lockout or may cause a freeze
rupture of the heat exchanger.
Important – Figure 4 shows that Pressure/Temperature
(P/T) ports must be installed in the entering and leaving
water lines of the heat pump. A thermometer can be
inserted into the P/T ports to check entering and leaving
water temperatures. A pressure gauge can also be inserted
into these P/T ports to determine the pressure differential
between the entering and leaving water. This pressure
differential can then be compared to the specification data
on each particular heat pump to confirm the proper flow
rate of the system.
An individually sized Enertech flow center can supply
pumping requirements for the Ground Loop fluid, and can
also be used to purge the loop system. Note – Refer to
instructions included with the flow center for detail for
properly purging the ground loop.
Important – the pump must be installed to supply fluid
into the heat pump.
Filling and purging a loop system are very important steps
to assure proper heat pump operation. Each loop must be
purged with enough water flow to assure a two-feet-persecond flow rate in each circuit on the loop. This
normally requires a 1½ to 3 HP high head pump to
circulate fluid through the loop to remove all the air out of
the loop and into a purging tank. Allow the pump to run
10 to 15 minutes after the last air bubbles have been
removed. After purging is completed, add the calculated
proper amount of antifreeze to give a 12 oF to 15oF freeze
protection. After antifreeze has been installed and
thoroughly circulated, it should be measured with a
hydrometer, refractometer or any other suitable device to
determine the actual freezing point of the solution.
The purge pump can be used to pressurize the system to a
final static pressure of 30-40 psig after the loop pipe has
had enough time to stretch. In order to achieve the 30 to
40 psig final pressure, the loop may need to be
pressurized to 60 to 65 psi. This static pressure will
fluctuate 10 psig from heating to cooling season, but the
pressure should always remain above 20 psig, so
circulation pumps do not cavitate or pull air into the
system. Contact your local installer, distributor or
factory representative for more information.
B. Ground Water Installation
A Ground Water system gets its name from the open
discharge of water after it has been used by the heat
pump. A well must be available that can supply all of the
water requirements (see Table 1) of the heat pump for up
to 24 hours/day on the coldest winter day plus any other
water requirements drawing off that same well.
Figure 5 shows the necessary components for ground
water piping. First, a bladder type pressure tank with a
“draw down” of at least 1½ times the well pump capacity
must be installed on the supply side of the heat pump.
Shut off valves and boiler drains on the entering and
leaving water lines are necessary for future maintenance
issues.
Important – A screen strainer must be placed on the
supply line with a mesh size of 40 or 60 and enough
surface area to allow for particle buildup between
cleanings.
Important – Pressure/Temperature (P/T) ports must be
placed in the supply and discharge lines so that
thermometers or pressure gauges can be inserted into the
water stream.
Important – A visual flow meter must be installed to
allow visual inspection of the flow to determine when
maintenance is required. (If you can’t read the flow,
cleaning is required. See Water Coil Maintenance for
cleaning instructions.)
A solenoid control valve must be installed on water
discharge side of the heat pump to regulate the flow
through the unit. Wire the solenoid to the “Plug
Accessory” connector on the controller. This valve opens
when the unit is running and closes when the unit stops.
Schedule 40 PVC piping, copper tubing, polyethylene or
rubber hose can be used for supply and discharge water
lines. Make sure line sizes are large enough to supply the
required flow with a reasonable pressure drop (generally
1” diameter minimum).
Water discharge is generally made to a drain field, stream,
pond, surface discharge, tile line, or storm sewer.
Important – ensure the discharge line has a pitch of at
least three inches per 12 feet, has a minimum 2 feet of
unobstructed freefall at the end of the line, and has at least
100 feet of grade sloping away from the discharge outlet.
CAUTION – A drain field requires soil conditions and
adequate sizing to assure rapid percolation. Consult local
codes and ordinances to assure compliance. DO NOT
discharge the water into a septic system.
CAUTION – Never operate with flow rates less than
specified. Low flow rates, or no flow, may cause the unit
to shut down on a pressure lockout or may cause a freeze
rupture of the heat exchanger.
1. Ground Water Freeze Protection
CAUTION – Only specifically ordered equipment with
a factory-installed 60 psig low-pressure switch can be
used on ground water applications. (The low-pressure
switch on a R410a ground loop system has a 35 psig
(previously 50) nominal cutout pressure.) If the water
supply to the heat pump were interrupted for any reason,
continued operation of the compressor would cause the
water remaining in the heat exchanger to freeze and
rupture the heat exchanger and may void warranty.
2. Water Coil Maintenance
Water quality is a major concern for ground water
7
systems. Problems can occur from scaling, particle
buildup, suspended solids, corrosion, pH levels outside
the 7-9 range, biological growth, or water hardness of
greater than 100-PPM. If poor water quality is known to
exist in your area, a cupro-nickel water coil may be
required when ordering the system; or installing a ground
loop system may be the best application. Water coil
cleaning on ground water systems may be necessary on a
regular basis. Depending on the specific water quality
issue, the water coil can be cleaned by the following
methods (Note – always remember to clean the strainer.):
a. Chlorine Cleaning (Bacterial Growth)
1. Turn off all power to the heat pump during this
procedure.
2. Close the shut-off valves upstream and downstream of
the heat exchanger.
3. Connect a submersible pump to the hose bibs on the
entering and leaving water sides of the heat exchanger.
4. Submerse the pump in a five-gallon pail of water with
enough chlorine bleach to kill the bacteria. Suggested
mixture is 1 part chlorine bleach to 4 parts water.
5. Open the hose bibs to allow circulation of the solution.
6. Start the pump and circulate the solution through the
heat exchanger for 15 to 60 minutes. The solution
should change color to indicate the chlorine is killing
and removing the bacteria from the heat exchanger.
7. Flush the used solution down a drain by adding a fresh
water supply to the pail. Flush until the leaving water
is clear.
8. Repeat this procedure until the solution runs clear
through the chlorine circulation process.
This procedure can be repeated annually, semiannually, or
as often as it takes to keep bacteria out of the heat
exchanger, or when bacteria appears in a visual flowmeter
to the point the flow cannot be read.
Another alternative to bacteria problems is to shock your
entire well. Shocking your well may give longer term
relief from bacteria problems than cleaning your heat
exchanger, but will probably need to be repeated, possibly
every three to five years. Contact a well driller in your
area for more information.
b. Muriatic Acid Cleaning (Difficult Scaling and
Particle Buildup Problems)
1. WARNING – Consult installer because of the
dangerous nature of acids. Only an experienced and
trained professional should perform this procedure.
(Note – CLR, Iron-Out or other de-scaling products
may be a better alternative before using muriatic acid.)
2. Turn off all power to the heat pump during this
procedure.
3. Close the shut-off valves upstream and downstream of
the heat exchanger.
4. Connect a submersible circulating pump to the hose
bibs on the entering and leaving water sides of the heat
exchanger. Note – these are corrosive chemicals, so
use a disposable or a suitable pump.
5. Submerse the pump in a five-gallon pail of water with
8
6.
7.
8.
9.
a small amount of muratic acid to create a final
concentration of 5% muratic acid.
WARNING – Always add acid to water; never add
water to acid.
Open the hose bibs to allow circulation.
Start the pump and circulate the solution through the
heat exchanger for about 5 minutes until there are no
longer any air bubbles.
Stop the pump, and let the solution stand for about 15
minutes.
Flush the solution by adding a fresh water supply to
the pail. Flush until the leaving water is clear. Note –
observe local codes for disposal.
c. Freeze Cleaning (Scale/Particle Buildup)
This applies only to cupro nickel heat exchangers,
cylinder shape, used on ground water applications.
WARNING – Never attempt this process on a braze
plate heat exchanger. It could cause the braze plate heat
exchanger to rupture and may void warranty.
I. Before using the freeze cleaning procedure, verify it
needs to be done by answering the following questions.
1. Determine and verify that the required water flow rate
in GPM is both present and correct.
2. Determine the temperature differential of the water.
Under normal conditions in the cooling mode, there
should be a temperature difference of about 10-15°F
between the supply side and discharge side. If the
temperature difference is 8°F or less, consideration
should be given to cleaning the water coil.
II. If the water coil requires cleaning, carefully use the
following steps for the freeze cleaning method.
1. Turn off the heat pump and its water supply.
2. Open a plumbing connection on the water supply side,
if possible, to break the system vacuum and allow
easier drainage of the system and water coil.
3. Drain the water out of the system and water coil via the
boiler drains on the entering and leaving water lines,
and the drain on the heat exchanger.
WARNING – FAILURE TO COMPLETELY DRAIN
THE WATER COIL HEAT EXCHANGER COULD
POSSIBLY RESULT IN A FREEZE RUPTURE!
4. Set the thermostat to "Heat" to start the heat pump in
the heating mode and quickly freeze the coil.
5. Allow the heat pump to run until it automatically shuts
off on low pressure and then turn the thermostat to the
"Off" position.
6. Recap the water coil drain and tighten any plumbing
connections that may have been loosened.
7. If so equipped, open the field installed drain cock on
the water discharge side of the heat pump, and install a
short piece of rubber hose to drain into a drain or
bucket. A drain cock on the discharge side allows
water flow to bypass the solenoid valve, flow valve,
flow meter, or any other item that may be clogged by
mineral debris. Draining to a bucket helps prevent
clogging of drains and allows observing effectiveness
of the procedure.
8. Turn on the water supply to the heat pump to start the
process of flushing any mineral debris from the unit.
9. Set the thermostat to "Cool" and start the heat pump in
the cooling mode to quickly thaw out the water coil.
10. Run the heat pump until the water coil is completely
thawed out and loosened scale, mineral deposits, or
other debris is flushed completely from the water coil.
Allow at least five minutes of operation to ensure that
the water coil is thoroughly thawed out.
11. If the water still contains mineral debris, and if the
flow through the unit did not improve along with an
increase in the temperature difference between the
water supply and water discharge, repeat the entire
procedure.
12. Reset the heat pump for normal operation.
VIII. ELECTRICAL SERVICE
 Note – Always refer to the inside of the electrical box
cover for the correct wiring diagram, and always refer
to the nameplate on the exterior of the cabinet for the
correct electrical specifications.
WARNING – ELECTRICAL SHOCK CAN CAUSE
PERSONAL INJURY OR DEATH. Disconnect all
power supplies before installing or servicing electrical
devices. Only trained and qualified service personnel
should install, repair or service this equipment.
WARNING – THE UNIT MUST BE PROPERLY
GROUNDED!
The main electrical service must be protected by a fuse or
circuit breaker, and be capable of providing the amperes
required by the unit at nameplate voltage. All wiring shall
comply with the national electrical code and/or any local
codes that may apply. Access to the line voltage contactor
is gained through the knockouts provided on either side of
the heat pump next to the front corner. Route EMT or
flexible conduit with appropriate size and type of wire.
Ensure adequate supply wiring to minimize the level of
dimming lights during compressor startup on single-phase
installations. Some dimming is normal, and a variety of
start-assist accessories are available if dimming is
objectionable. Important – some models may already
have a factory-installed start assist. Do not add additional
start assists to those units.
CAUTION – Route field electrical wiring to avoid
contact with electrically live bare metal parts inside the
electrical box and to avoid contact with the surface of the
factory-installed start assist (if provided).
CAUTION – Disconnect power from the unit before
removing or replacing any connectors, or servicing the
ECM motor. To avoid electric shock from the motor’s
internal capacitors, disconnect the power and wait at least
5 minutes before opening the motor.
CAUTION – Three-phase units must be wired properly
to ensure proper compressor rotation. Improper rotation
may result in compressor damage. An electronic phase
sequence indicator must be used to check supply-wiring
phases. Also, the “Wild” leg of the three-phase power
must be connected to the middle leg on the contactor.
Important – Only 208Vac FlowCenters can be wired
directly to the compressor contactor and can be grounded
in the grounding lug for 208/230Vac. An alternative loop
pump or a pump for a different supply voltage must be
powered from a separate fused power supply and
controlled through an isolation relay that has its coil wired
to the contactor circuit.
Important – Units with internal installed Supplemental
Electric Heat require a separate power supply for the
Supplemental Electric Heat.
IX. 24 VOLT CONTROL
CIRCUIT
Note – Always refer to the inside of the electrical box
cover for the correct wiring diagram
There are three basic sections of the low voltage circuit;
transformer, thermostat, and controller.
A. Transformer
An internal transformer provides 24Vac for all control
features of the heat pump. Even though the transformer is
larger than the industry standard, it is in a warm electrical
box and can be overloaded quickly. Table 5 shows the
transformer usage for the Vara 2 Plus heat pumps.
Table 5 – Transformer Usage (VA)
Component
Contactor
Reversing Valve
Compressor Solenoid
Controller 20-1038
Thermostat
Blower Motor
Elec. Heat Relay
Plug Accessory (PA)
Total
Transformer VA size
VA
7
8
4
2
1
2
6
10
40 VA
50
Important - If the system’s external controls require
more than shown in table 5, an external transformer and
isolation relays should be used.
Important – Miswiring of 24Vac control voltage on
system controls can result in transformer burnout.
Important – Units with a dual voltage rating (example,
208/230) are factory-wired for the higher voltage
(example, 230). If connected to a power supply having the
lower voltage, change the wiring to the transformer
primary to the correct lead; otherwise premature failure,
or inability to operate the control components may occur.
B. Thermostat
9
A 3-heat/2-cool thermostat must be used with every Vara
2 Plus heat pump. This thermostat controls all stages of
operation of the heat pump. Initiation of each stage is
implemented based on the recovery rate of the actual
temperature to the set point temperature. This means that
switching to a higher stage will require time (sometimes
15 minutes or more) for the thermostat to calculate rate of
change. Consult the instructions in the thermostat box for
proper mounting and operation.
Important – Be careful to select a thermostat location
where external temperature sources will not affect sensed
temperature.
Important – If a single thermostat controls multiple
heat pumps, the control wiring of the heat pumps must be
isolated from each other. This will prevent the heat
pumps from receiving high voltage through the common
wiring if it is turned off at the circuit breaker for service.
Important – Thermostat cable with at least nine
conductors must be run from the heat pump to the
thermostat. Power is supplied to the thermostat by
connecting the R and X (C) terminals to the heat pump
terminal strip.
C. Controller
The controller receives a signal from the thermostat and
initiates the correct sequence of operations for the heat
pump. The controller performs the following functions:
1) Compressor Anti-Short-Cycle
2) Ground Loop Pump / Ground Water Pump Initiation
3) ECM Blower Operation and Speed Control
4) Compressor Operation for 1st Stage Heat/Cool
5) Compressor Operation for 2nd Stage Heat/Cool
6) Supplemental Electric Heat Operation
7) 4-Way Valve Control
8) Compressor Lockouts
9) Defrost
10) System Diagnostics
11) 24Vac Fuse
12) Plug Accessory
13) Alarm Output
1. Compressor Anti-Short-Cycle
An anti-short-cycle is a delay period between the times a
compressor shuts down and when that compressor is
allowed to come on again. This protects the compressor
and avoids nuisance lockout conditions. Anti-shortcycles occur after these three conditions;
1. A 70 to 130-second random time-out period occurs
before a re-start after the last shut down.
2. A 4-minute/25-second to 4-minute/45-second randomstart delay occurs immediately after power is applied
to the heat pump. This occurs only after reapplying
power to the unit. To avoid this timeout while
servicing the unit, apply power, disconnect and
reapply power very quickly to shorten the delay.
Note – The thermostat supplied with the heat pump is
factory programmed to have a five-minute delay period
after compressor shutdown before it will start again. A
10
“Wait” indicator on the thermostat shows this delay. This
delay can be reprogrammed to be from zero to five minutes.
2. Ground Loop Pump / Ground Water
Initiation
On ground loop systems, a M1 output from the controller
will energize the contactor, starting the compressor and
the ground loop pump. On ground water systems, a M1
output from the controller will energize the ground water
solenoid valve through the “Plug Accessory” connector.
3. ECM Blower Operation and Speed
Control
A signal on the G terminal from the thermostat to the
controller will tell the controller to energize the blower. A
G signal alone puts the motor in low speed operation. If
the thermostat sends a G and Y signal to the controller for
1st stage operation, the controller bumps the blower speed
up to Medium-Low. When the thermostat sends a G, Y,
and Y2 signal for 2nd stage operation, the controller
bumps the blower speed up to Medium-High. An input to
W2 (3rd stage heat) or E (Emergency heat) from the
thermostat energizes the blower in High speed. These
configurations are shown in Table 4.
The CFM outputs are factory set, and should not be
changed in the field. There is an “Adjust” setting, which
allows the blower to be operated at +/-10% of the factory
setting. For example, if the Adjust tap is set to the “-,”all
the speeds will operate at 90% of the factory setting. If the
“Adjust” tap is set to the “+,” all the speeds will operate at
110% of the factory setting. The Adjust tap is the only tap
on the blower speed controller that should ever be moved
from the factory setting.
Important – Power to the unit will have to be reset
before the new settings are enabled. The blower motor
also provides internal circuitry that will try to maintain
the setpoint CFM when changes occur in the external
static pressure, such as the filter getting dirty over time.
The motor does this by increasing its torque output to
compensate for external resistance changes.
Important – The ECM motor is Factory programmed
with delay profiles for start and stop to ensure the blower
motor slowly ramps up to the proper CFM output and
backs down after the run time is complete. Ramping of
the ECM motor allows for quieter operation and increased
comfort. It may take a few seconds for the blower to start
when the thermostat initially calls for heating or cooling,
and for the blower to stop after the thermostat is satisfied.
4. Compressor Operation for 1st Stage
Heat/Cool
A Y input from the thermostat will ask the controller to
initiate 1st stage heating or cooling (when combined with
an O input). The controller then decides, based on lockout
and anti-short-cycle periods, when to bring the
compressor on. The M1 output of the controller energizes
the compressor contactor, and the compressor stays on
until the 24Vac is removed from the Y terminal.
5. Compressor Operation for 2nd Stage
Heat/Cool
An input to Y2 from the thermostat will ask the controller
to initiate 2nd stage heating or cooling. The unit will then
energize the solenoid coil on the compressor, allowing
full compressor capacity.
6. Supplemental Electric Heat Operation
Top discharge vertical units have the option of factoryinstalled supplemental electric heat (Use a separate ductinstalled heater for Bottom Discharge and Horizontal
applications.) There is a jumper plug on the 20-1038
controller marked J2 that ties a W2 signal to E. This
jumper must be removed for 5 kW of supplemental heat,
and 10 kW of emergency heat. If the J2 jumper is not
removed from the control board the heater will supply the
full 10 kW during either supplemental or emergency heat
modes.
When the electric elements are energized, a third-stage
latch wired to W2 on the controller is also energized. The
third-stage latch enables the auxiliary heat stage of the
room thermostat to assist in cycling the compressor to
reduce the long periods of uninterrupted compressor
operation. Once energized, the latch remains on until the
Y2 stage is satisfied on the thermostat.
air filter or airside heat exchanger, may result in an iced
up air coil and/or a low-pressure lockout. The controller
will automatically switch the heat pump to defrost mode
if this occurs. While in the cooling mode if the lowpressure switch opens for two continuous seconds the O
input will be taken away to start the unit in heating. This
defrost mode will last for approximately 80 seconds, then
the unit will go to the power up anti-short cycle time
delay. After the unit has timed out, the heat pump will be
able to resume normal operation.
CAUTION – If the heat pump continually goes to
defrost mode, the cause of the low-pressure lockout must
be determined. A service technician should be called
immediately to resolve the issue.
10. System Diagnostics
The controller is equipped with diagnostic LED lights,
which indicate the system status at any particular time.
The lights indicate the following conditions:
1. 24 Volt system power
GREEN
2. Fault or Lockout
YELLOW
3. Anti-short-cycle mode
RED
If a room thermostat installed with the heat pump system
has a lockout indicator, the controller will send a signal
from “L” on the terminal strip to a LED on the thermostat
to indicate a lockout condition.
11. 24 Vac Fuse
When 24Vac is applied to O terminal on the wiring block,
the controller energizes its O output to provide 24Vac
power to the 4-way reversing valve (VR) in order to
switch the refrigerant circuit to the cooling mode.
The controller has a glass-cartridge fuse located on the
circuit board adjacent to the 24Vac power connector. The
green system power LED will be off if this fuse is open.
A spare fuse is located in the saddle attached to the side of
the 24Vac power connector.Note – Ensure the new fuse
fits tightly in the fuse clips after replacement.
8. Compressor Lockouts
12. Plug Accessory (PA)
7. 4-Way Valve Control
The controller will lock out the compressor if either the
high-pressure 600 psig or the low-pressure 35 psig
(previously 50) on ground loop or 60 psig on ground
water switch opens. This lockout condition means that the
unit has shut down to protect itself, and will not come
back on until power has been disconnected (via the circuit
breaker) to the heat pump for one minute. Problems that
could cause a lockout situation include:
1. Water flow or temperature problems
2. Air flow or temperature problems
3. Cold ambient air temperature conditions
4. Internal heat pump operation problems
If a lockout condition exists, the heat pump should not
be reset more than once; and a service technician should
be called immediately.
CAUTION – Repeated reset may cause severe damage
to the system and may void warranty. The cause of the
lockout must be determined and corrected.
9. Defrost
Restricted airflow in the cooling mode, caused by a dirty
The Plug Accessory output is internally connected to the
M1 output and is energized whenever M1 turns on the
compressor contactor. The maximum rating of this output
is 10VA sealed and 20VA inrush and is typically intended
to power a 24Vac ground water solenoid valve.
13. Alarm Output
This output is a two-position screw terminal connector
identified as “Fault Test” on the controller board and as
DO on the wiring diagram. It is an isolated dry contract
output (0.1 ohm resistance) that closes during a controller
lockout and is intended for use as an input to a dial-out
type of monitoring system. The maximum electrical rating
is 2mA up to 30Vac or 50mA up to 40Vdc.
X. STARTUP / CHECKOUT
Before applying power to the heat pump, check the
following items:
 Water supply plumbing to the heat pump is
11


completed and operating. Manually open the water
valve on well systems to check flow. Make sure all
valves are open and air has been purged from a loop
system. Never operate the system without correct
water flow.
All high voltage and low voltage wiring is correct
and checked out, including wire sizes, fuses and
breakers, set thermostat to the “OFF” position.
The heat pump is located in a warm area (above
45oF). Starting the system with low ambient
temperature conditions is more difficult; do not leave
until the space is brought up to operating
temperatures.
You may now apply power to the unit. A 4 minute 35
second delay on power up is programmed into the heat
pump before the compressor will operate. During this
time you can verify airflow with the following procedure:
 Place the thermostat in the “FAN ON” position. The
blower should start in low speed. Check airflow at
the registers to make sure that they are open and that
air is being distributed throughout the house. When
airflow has been checked, move the thermostat to the
“FAN AUTO” position. The blower should stop.
The following steps will assure that your system is
heating and cooling properly. After the initial time-out
period, the red indicator light on the internal controller
will shut off. The heat pump is now ready for operation.
 With the thermostat in the “HEAT” mode, turn the
thermostat up to its highest temperature setting. The
compressor should start, with the blower starting a
few seconds later. The thermostat may cause its own
compressor delay at this time (shown by “Wait” on
the thermostat) but the compressor will start after all
delays.
 After running the unit for five minutes, check the
airside return and supply temperatures. An air
temperature rise of 20oF to 30oF is normal in the
heating mode, but variations in water temperature
and water flow rate can cause variations outside the
normal range. Use a single pressure gauge to check
the fluid pressure drop through the heat exchangers to
ensure proper flow for the system.
 Turn the thermostat to the “OFF” mode. The
compressor will shut down in a few seconds, with the
blower stopping shortly after.
 Next, set the thermostat to “COOL” and turn down to
its lowest setting. The compressor will start after an
anti-short cycle period of 70 to 130 seconds from its
last shutdown, and the blower will start a few
seconds later. The anti-short cycle period is indicated
by the red light (labeled ASC) on the controller.
 After the unit has run in cooling for five minutes,
check the airside return and supply temperatures. An
air temperature drop of 15oF to 20oF is normal in the
cooling mode but airflow and humidity can affect
temperature drop. Use a single pressure gauge to
check the fluid pressure drop through the heat
12


exchangers to ensure proper flow for the system.
Set the thermostat for normal operation.
Instruct the owner on correct operation of the entire
heat pump system. The unit is now operational.
XI. SERVICE
Properly installed, the ECONAR Vara 2 Plus heat pump
requires only minor maintenance such as periodic
cleaning of the air coil, air filter, and the ground water
heat exchanger on a Ground Water system. Setting up
regular service checkups with your Enertech dealer
should be considered. Any major problems with the heat
pump system operation will be indicated on the lockout
lights.
CAUTION – During evacuation of refrigerant of a
system not having antifreeze protection of a water-side
heat exchanger, water in the unprotected heat exchanger
must be removed or continuously flowing to avoid a
potential heat exchanger failure caused by freeze rupture.
CAUTION – Service on systems using R410A
refrigerant requires special consideration (Refer to
ECONAR Instruction 10-2016 for more detail.). Always
install a new filter/dryer after replacing a refrigeration
component (compressor, etc.) and evacuate down to 150
microns.
A. Air Filter
The Vara 2 Plus heat pump includes an electrostatic air
filter. This filter can be cleaned and reused after it
becomes dirty. This filter should normally be cleaned
once a month during normal usage. During extreme usage
or if system performance has decreased, the filter should
be cleaned more often.
A dirty filter will increase static pressure to the system.
This increase in static pressure will cause the variable
speed blower to increase its speed in order to maintain
airflow levels. This increase in speed will consume more
power than normal, reducing the efficiency of the system.
In extreme cases, the blower will not be able produce the
correct amount of airflow. In the heating mode, reduced
airflow may increase the cost of operation and, in extreme
cases, cause system lockout due to high refrigerant
pressures. In the cooling mode, reduced airflow may
reduce cooling capacity and, in extreme cases, ice the air
coil over causing system shutdown due to low refrigerant
pressures.
This washable electrostatic air filter can be cleaned by
spraying water through the filter in the opposite direction
of the indicated airflow. This can be done outside or in a
garage with a garden hose, or in a large sink. Soap may
also be used to provide extra cleaning. Light dirt may be
vacuumed off.
If a different filter is used in place of the factory-supplied
filter, it should also be cleaned or changed in a timely
manner. Be careful in selecting optional filters so that
excessive external resistance to airflow is not induced.
B. Lockout Lights
The heat pump controller and room thermostat will
display a system lockout. If lockout occurs, follow the
procedure below:
1. Determine and record which indicator lights on the
Controller are illuminated. (Refer to Section XIV for
more information on possible causes of Lockout
Conditions.)
2. Check for a clean air filter and correct water supply
from the ground loop or ground water system.
3. Reset the system by disconnecting power at the
circuit breaker for one minute, and then reapplying
power.
4. If shutdown reoccurs,  call your Enertech dealer.
Do not continuously reset the lockout condition or
damage may occur. Note – Improper fluid flow,
airflow, or incorrect antifreeze levels are the cause
of almost all lockouts.
C. Preseason Inspection
Before each season, the air coil, drain pan, and condensate
drain should be inspected and cleaned as follows:
 Turn off the circuit breakers.
 Remove the access panels.
 Clean the air coil by vacuuming it with a soft-brush
attachment.
 Remove any foreign matter from the drain pan.
 Flush the pan and drain tube with clear water.
 Replace the access panels and return power to the
unit.
XII. ROOM THERMOSTAT
OPERATION
Installations may include a wide variation of available
electronic room thermostats, and most of them require to
be configured by the Installer (according to the
Installation Guide included with the thermostat) and
checked out after being installed.
Important – At a minimum:
1. Ensure the thermostat is set up for the “System Type”
it is installed on.
2. Ensure the thermostat is configured for “Manual
Heat/Cool Changeover.”
3. Change other Installer Settings only if necessary.
4. Remember to press “Done” to save the settings and to
exit “Installer Setup.”
5. Run the system through all modes of operation in the
thermostat instructions to ensure correct operation.
If you have additional questions about your thermostat,
please refer to the installation manual that was sent with
the thermostat.
XVI. DESUPERHEATER
(OPTIONAL)
A Vara 2 Plus heat pump equipped with a desuperheater
can provide supplemental heating of a home’s domestic
hot water. This is done by stripping heat from the
superheated gas leaving the compressor and transferring it
to a hot water tank. A desuperheater pump, manufactured
into the unit, circulates water from the domestic hot water
tank, heats it using a double walled water-to-refrigerant
heat exchanger, and returns it to the tank.
The desuperheater only provides supplemental heating
when the compressor is already running to heat or cool
the conditioned space. Because the desuperheater is using
some energy from the heat pump to heat water, the heat
pump’s capacity in the winter is about 10% less than a
unit without a desuperheater. During extremely cold
weather, or if the heat pump cannot keep up with heating
the space, the desuperheater fuse may be removed to get
full heating capacity out of the unit.
WARNING – Do not remove the desuperheater’s high
temperature cutout switch, or tank temperatures could
become dangerously high. The desuperheater's high
temperature cutout switch is located on the return line
from the water heater and is wired in series with the
desuperheater pump to disable it from circulating at
entering water temperature above 140oF. If the tank
temperatures become uncomfortably hot, move this
switch to the leaving water line, which will reduce the
tank maximum temperatures 10oF to 15oF.
CAUTION – Running the desuperheater pump without
water flow will damage the pump. A fuse is attached to
the fuseholder and must be inserted in the fuseholder
after the desuperheater is operational.
Important – Do not insert the fuse until water flow is
available, or the pump may be damaged. Remove the fuse
to disable the pump if the desuperheater isn’t in operation.
All air must be purged from the desuperheater plumbing
before the pump is engaged. To purge small amounts of
air from the lines, loosen the desuperheater pump from its
housing by turning the brass collar. Let water drip out of
the housing until flow is established, and re-tighten the
brass collar. Using 1/2-inch copper tubing from the tank
to the desuperheater inlet is recommended to keep water
velocities high, avoiding air pockets at the pump inlet. An
air vent in the inlet line can also help systems where air is
a problem. If one is used (we recommend a Watts
Regulator brand FV-4 or Spirovent) mount it near the
desuperheater inlet roughly 2-1/2 inches above the
horizontal pipe. Shutoff valves allow access to the
desuperheater plumbing without draining the hot water
13
tank. Keep valves open when the pump is running.
Desuperheater maintenance includes periodically opening
the drain on the hot water tank to remove deposits. If hard
water, scale, or buildup causes regular problems in hot
water tanks in your area, it may result in a loss of
desuperheater effectiveness. This may require periodic
cleaning with Iron Out or similar products.
CAUTION – Insulated copper tubing must be used to
run from the hot water tank to the desuperheater
connections on the side of the unit.
The built-in desuperheater pump can provide the proper
flow to the desuperheater if the total equivalent length of
straight pipe and connections is kept to a maximum of 90
feet of ½-inch type L copper tubing (or a combination of
approximately 60 feet with typical elbows and fittings).
This tubing can be connected to the water tank in two
ways:
14
METHOD 1
Using a desuperheater tee installed in the drain at the
bottom of the water heater (See Figure 6). This is the
preferred method for ease of installation, comfort and
efficiency. The tee eliminates the need to tap into the
domestic hot water lines and eliminates household water
supply temperature variations that could occur from
connecting to the hot water pipes. Poor water quality may
restrict the effectiveness of using the desuperheater tee by
plugging the entrance with scale or buildup from the
bottom of the tank, restricting water flow.
METHOD 2
Taking water from the bottom drain and returning it to
the cold water supply line (See Figure 7). This method
maintains the same comfort and efficiency levels but
increases installation time and costs.
Important – This method requires a check valve in the
return line to the cold water supply to prevent water from
flowing backwards through the desuperheater when the
tank is filling. Water passing through the pump
backwards damages the rotor’s bearing, which reduces
pump life and causes noise problems in the pump.
Note – A spring-type check valve with a pressure-drop
rating of 1/2 psig or less is recommended.
XIV. Performance Ratings
Ground Loop
AHRI/ISO 13256-1
MODELS
EV 380/381
EV 480/481
EV 580/581
1st Stage
CFM
910
GPM
9
2nd Stage
1,180
9
EV 580/581
30,500
38,000
3.5
HEATING
41oF EWT
BTU/hr COP
23,300
3.9
COOLING
68oF EWT
BTU/hr
EER
28,900
22.0
14.4
--
--
--
-23.9
1st Stage
1,295
12
--
--
--
--
31,500
3.9
40,000
1,680
12
39,800
3.4
49,000
15.8
--
--
--
--
1st Stage
1,400
15
--
--
--
--
37,500
3.8
49,000
22.5
2nd Stage
1,800
15
48,600
3.4
60,000
15.5
--
--
--
--
Ground Water
EV 480/481
COOLING
77oF EWT
BTU/hr
EER
---
2nd Stage
AHRI/ISO 13256-1
MODELS
EV 380/381
HEATING
32oF EWT
BTU/hr COP
---
1st Stage
CFM
900
GPM
9
HEATING
50oF EWT
BTU/hr
COP
---
COOLING
59oF EWT
BTU/hr
EER
---
HEATING
50oF EWT
BTU/hr
COP
27,000
4.4
COOLING
59oF EWT
BTU/hr
EER
32,000
27.0
2nd Stage
1150
9
38,000
4.1
43,000
20.9
--
--
--
--
1st Stage
1,295
12
--
--
--
--
35,000
4.2
41,000
27.0
2nd Stage
1,680
12
50,000
4.0
53,000
19.0
--
--
--
--
1st Stage
1,400
15
--
--
--
--
44,000
4.2
51,000
26.9
2nd Stage
1,800
15
62,000
3.9
64,000
19.4
--
--
--
--
Configuration Options
Model Suffix
Description
Standard, No Desuperheater
Exxx0-x-Vxxx
Desuperheater
Exxx1-x-Vxxx
Standard, 208/230-1, 60 Hz
Exxxx-1-Vxxx
208/230-3, 60Hz
Exxxx-2-Vxxx
Standard, Vertical Left Side Air Return
EVxxx-x-VOxx
Right Side Return
EVxxx-x-VRxx
Bottom Discharge (right return)
EVxxx-x-VBCx
Standard Earth Loop Coil
Exxxx-x-VxxO
Cupro-Nickel Well Water Coil
Exxxx-x-VxxN
Note: All Vara 2 Plus units are 208/230 VAC, Single Phase, 60 Hz
38
*





48
*





58
*





1
*
1
*
1
*
1
Brazed Plate Ground Loop Heat Exchanger
 Standard
 Special Order
15
XV. Performance Data
EV 380/381
Loop
EWT
15
20
25
30
35
45
50
60
70
Loop
EWT
40
50
60
70
75
80
85
90
95
Loop
GPM
8
9
10
8
9
10
8
9
10
8
9
10
8
9
10
5
6
9
5
6
9
5
6
9
5
6
9
Loop
GPM
5
6
9
5
6
9
5
6
9
5
6
9
8
9
10
8
9
10
8
9
10
8
9
10
8
9
10
dP
ft
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
2.8
3.7
7.2
2.8
3.7
7.2
2.8
3.7
7.2
2.8
3.7
7.2
dP
ft
2.8
3.7
7.2
2.8
3.7
7.2
2.8
3.7
7.2
2.8
3.7
7.2
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
5.8
7.2
8.8
dP
psi
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
1.2
1.6
3.1
1.2
1.6
3.1
1.2
1.6
3.1
1.2
1.6
3.1
dP
psi
1.2
1.6
3.1
1.2
1.6
3.1
1.2
1.6
3.1
1.2
1.6
3.1
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
2.5
3.1
3.8
MBTU/hr
14.1
14.2
14.4
15.8
16.0
16.1
17.5
17.7
17.9
19.3
19.5
19.7
21.0
21.2
21.4
23.3
23.7
24.7
24.9
25.4
26.5
28.5
28.8
30.0
31.8
32.1
33.5
Heating @ 68oF EAT
First Stage @ 900 cfm
Suct
Head
KW
COP
Press
Press
1.7
2.3
63-73
280-300
1.7
2.3
64-74
285-305
1.7
2.3
65-75
290-310
1.8
2.6
71-81
290-310
1.8
2.6
72-82
295-315
1.8
2.6
73-83
300-320
1.8
2.9
78-88
300-320
1.8
2.9
79-89
305-325
1.8
3.0
80-90
310-330
1.8
3.2
85-95
310-330
1.8
3.2
86-96
315-335
1.8
3.3
87-97
320-340
1.8
3.5
92-102
320-340
1.9
3.5
93-103
325-345
1.9
3.6
94-104
330-350
1.9
4.0
107-117 335-355
1.9
4.1
108-118 340-360
1.9
4.2
110-120 350-370
1.9
4.4
102-112 320-340
1.9
4.5
103-113 325-345
1.9
4.6
105-115 330-350
1.9
4.9
115-125 335-355
2.0
5.0
116-126 340-360
2.0
5.1
118-128 345-365
2.0
5.5
129-139 355-375
2.0
5.6
130-140 360-380
2.1
5.7
132-142 365-385
MBTU/hr
35.1
35.4
35.7
33.6
33.9
34.2
32.1
32.4
32.7
30.6
30.9
31.2
30.2
30.5
30.8
29.4
29.7
30.0
28.7
29.0
29.3
28.0
28.2
28.5
27.2
27.5
27.8
COOLING @ 80oF DB/67oF WB
First Stage @ 900 cfm
Suct
Head
KW
EER
Press
Press
0.8
34.8
134-144 185-205
0.8
36.3
134-144 180-200
0.8
38.1
134-144 175-195
1.0
31.2
134-144 205-225
0.9
32.5
134-144 200-220
0.9
34.1
134-144 195-215
1.1
27.5
134-144 225-245
1.1
28.7
134-144 220-240
1.1
30.1
134-144 215-235
1.3
23.9
134-144 255-275
1.3
24.9
134-144 250-270
1.3
26.1
134-144 245-265
1.4
23.6
134-144 260-280
1.3
24.1
134-144 255-275
1.3
24.6
134-144 250-270
1.4
21.6
134-144 275-295
1.4
22.1
134-144 270-290
1.4
22.5
134-144 265-285
1.5
19.7
134-144 285-305
1.5
20.1
134-144 280-300
1.5
20.5
134-144 275-295
1.6
17.7
134-144 295-315
1.6
18.1
134-144 290-310
1.6
18.5
134-144 285-305
1.7
15.8
134-144 305-325
1.7
16.1
134-144 300-320
1.7
16.4
134-144 295-315
Note: dP pressure drops apply to standard coils, and cupro-nickel ground water coils have higher pressure drops
16
MBTU/hr
23.4
23.6
23.8
25.5
25.8
26.0
27.6
27.9
28.2
29.8
30.1
30.4
31.9
32.2
32.5
35.1
35.8
36.5
37.2
37.9
38.7
41.7
42.1
43.0
45.9
46.4
47.3
Second Stage @ 1180 cfm
Suct
KW
COP
Press
2.5
3.0
57-67
2.6
3.0
58-68
2.6
3.1
59-69
2.6
3.1
64-74
2.6
3.2
65-75
2.6
3.2
66-76
2.7
3.3
71-81
2.7
3.3
72-82
2.7
3.4
73-83
2.7
3.5
77-87
2.7
3.5
78-88
2.8
3.5
79-89
2.8
3.6
84-94
2.8
3.6
85-95
2.8
3.7
86-96
2.9
3.8
95-105
2.9
3.9
96-106
2.9
4.0
98-108
2.7
4.0
102-112
2.7
4.1
103-113
3.0
4.1
105-115
3.1
4.3
115-125
3.1
4.4
116-126
3.1
4.4
118-128
3.2
4.6
129-139
3.2
4.7
130-140
3.2
4.7
132-142
Head
Press
280-300
285-305
290-310
290-310
295-315
300-320
300-320
305-325
310-330
310-330
315-335
320-340
320-340
325-345
330-350
335-355
340-360
345-365
345-365
350-370
355-375
365-385
370-390
375-395
385-405
390-410
395-415
MBTU/hr
44.4
44.8
46.6
43.0
43.4
45.1
41.5
41.9
43.6
40.1
40.5
42.1
40.9
41.4
41.8
40.2
40.6
41.0
39.5
39.9
40.3
38.7
39.1
39.5
38.0
38.4
38.7
Second Stage @ 1180 cfm
Suct
KW
EER
Press
1.7
25.2
125-135
1.7
26.3
125-135
1.6
27.6
126-136
1.9
22.1
126-136
1.9
23.0
126-136
1.9
24.2
127-137
2.2
19.0
129-139
2.1
19.8
129-139
2.1
20.8
128-138
2.4
15.9
128-138
2.4
16.5
128-138
2.3
17.4
127-137
2.5
15.4
130-140
2.4
15.7
130-140
2.4
16.0
130-140
2.6
13.7
130-140
2.6
14.0
130-140
2.5
14.2
130-140
2.7
12.0
131-141
2.7
12.3
131-141
2.6
12.5
131-141
2.8
10.4
131-141
2.8
10.6
131-141
2.8
10.8
131-141
2.9
8.7
132-142
2.9
8.9
132-142
2.9
9.0
132-142
Head
Press
165-185
160-180
150-170
205-225
200-220
190-210
250-270
245-265
235-255
290-310
285-305
275-295
295-315
295-315
290-310
315-335
315-335
310-330
340-360
340-360
335-355
360-380
360-380
355-375
380-400
380-400
375-395
EV 480/481
Loop
EWT
15
20
25
30
35
45
50
60
70
Loop
EWT
40
50
60
70
75
80
85
90
95
Loop
GPM
11
12
13
11
12
13
11
12
13
11
12
13
11
12
13
6
7
12
6
7
12
6
7
12
6
7
12
Loop
GPM
6
7
12
6
7
12
6
7
12
6
7
12
11
12
13
11
12
13
11
12
13
11
12
13
11
12
13
dP
ft
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
3.7
4.6
12.2
3.7
4.6
12.2
3.7
4.6
12.2
3.7
4.6
12.2
dP
ft
3.7
4.6
12.2
3.7
4.6
12.2
3.7
4.6
12.2
3.7
4.6
12.2
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
10.6
12.2
14.1
dP
psi
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
1.6
2
5.3
1.6
2
5.3
1.6
2
5.3
1.6
2
5.3
dP
psi
1.6
2
5.3
1.6
2
5.3
1.6
2
5.3
1.6
2
5.3
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
4.6
5.3
6.1
MBTU/hr
20.0
20.2
20.4
22.2
22.4
22.6
24.3
24.6
24.8
26.5
26.7
27.0
28.6
28.9
29.2
31.3
31.6
33.2
33.3
33.6
35.4
37.4
37.7
39.7
41.4
41.9
44.1
Heating @ 68oF EAT
First Stage @ 1295 cfm
Suct
Head
KW
COP
Press
Press
2.3
2.9
54-64
270-290
2.3
2.9
55-65
275-295
2.3
2.9
56-66
280-300
2.4
3.1
62-72
275-295
2.4
3.1
63-73
280-300
2.4
3.1
64-74
285-305
2.4
3.2
70-80
285-305
2.4
3.3
71-81
290-310
2.4
3.3
72-82
295-315
2.4
3.4
79-89
290-310
2.5
3.5
80-90
295-315
2.5
3.5
81-91
300-320
2.5
3.6
87-97
295-315
2.5
3.7
88-98
300-320
2.5
3.7
89-99
305-325
2.5
3.9
98-108
300-320
2.6
3.9
99-109
305-325
2.6
4.1
105-115 315-335
2.6
4.1
106-116 305-325
2.6
4.1
107-117 310-330
2.7
4.3
113-123 320-340
2.7
4.5
123-133 320-340
2.7
4.5
124-134 325-345
2.7
4.6
130-140 335-355
2.7
4.8
139-149 335-355
2.8
4.9
140-150 340-360
2.8
5.0
146-156 350-370
MBTU/hr
41.5
42.0
42.8
40.6
41.0
41.9
39.7
40.1
40.9
38.8
39.2
40.0
39.1
39.5
39.9
38.7
39.1
39.4
38.2
38.6
39.0
37.7
38.1
38.5
37.3
37.6
38.0
COOLING @ 80oF DB/67oF WB
First Stage @ 1295 cfm
Suct
Head
KW
EER
Press
Press
1.3
30.4
134-144 155-175
1.2
31.1
133-143 150-170
1.2
33.8
129-139 120-140
1.5
27.3
135-145 190-210
1.4
27.8
134-144 185-205
1.3
30.3
130-140 155-175
1.7
24.1
136-146 225-245
1.6
24.6
135-145 220-240
1.5
26.8
131-141 190-210
1.9
21.0
136-146 255-275
1.8
21.4
135-145 250-270
1.7
23.3
131-142 220-240
1.8
21.1
133-143 245-265
1.8
21.5
132-142 240-260
1.8
21.9
131-141 235-255
1.9
19.4
134-144 260-280
1.9
19.8
133-143 255-275
1.9
20.2
132-142 250-270
2.0
17.6
135-145 275-295
2.0
18.0
134-144 270-290
2.0
18.4
133-143 265-285
2.1
15.9
135-145 295-315
2.1
16.3
134-144 290-310
2.1
16.6
133-143 285-305
2.2
14.2
136-146 310-330
2.2
14.5
135-145 305-325
2.1
14.8
134-144 300-320
MBTU/hr
29.3
29.6
29.9
32.2
32.6
32.9
35.2
35.6
35.9
38.2
38.6
38.9
41.1
41.6
42.0
44.7
45.2
47.6
47.6
48.0
50.6
53.2
53.7
56.6
58.8
59.4
62.6
Second Stage @ 1680 cfm
Suct
KW
COP
Press
3.3
2.9
53-63
3.3
2.9
54-64
3.3
3.0
55-65
3.4
3.1
60-70
3.4
3.1
61-71
3.4
3.1
62-72
3.5
3.2
68-78
3.5
3.3
69-79
3.5
3.3
70-80
3.6
3.4
75-85
3.6
3.4
76-86
3.6
3.4
77-87
3.7
3.5
83-93
3.7
3.6
84-94
3.7
3.6
85-95
3.8
3.7
91-101
3.8
3.8
92-102
3.9
3.9
99-109
3.9
3.9
98-108
3.9
3.9
99-109
4.0
4.0
106-116
4.1
4.2
113-123
4.1
4.2
114-124
4.2
4.3
121-131
4.2
4.5
128-138
4.3
4.5
129-139
4.4
4.7
136-146
Head
Press
265-286
270-290
275-295
275-295
280-300
285-305
285-305
290-310
295-315
300-320
305-325
310-330
310-330
315-335
320-340
300-320
305-325
340-360
310-330
315-335
350-370
335-355
340-360
375-395
355-375
360-380
395-415
MBTU/hr
57.4
58.0
59.2
55.0
55.6
56.7
52.6
53.1
54.2
50.2
50.7
51.7
50.0
50.5
51.0
48.7
49.2
49.7
47.5
48.0
48.4
46.2
46.7
47.2
45.0
45.5
45.9
Second Stage @ 1680 cfm
Suct
KW
EER
Press
2.2
23.6
123-133
2.2
24.0
122-132
2.1
26.1
117-127
2.6
21.0
125-135
2.5
21.4
124-134
2.4
23.3
119-129
2.9
18.5
127-137
2.8
18.9
126-136
2.6
20.5
121-131
3.2
15.9
129-139
3.1
16.3
128-138
2.9
17.7
123-133
3.1
16.0
126-136
3.1
16.3
125-135
3.1
16.6
124-134
3.3
14.6
127-137
3.2
14.9
126-136
3.2
15.2
125-135
3.4
13.2
128-138
3.4
13.5
127-137
3.3
13.7
126-136
3.6
11.8
129-139
3.5
12.1
128-138
3.5
12.3
127-137
3.7
10.4
130-140
3.7
10.6
129-139
3.6
10.9
128-138
Head
Press
175-195
170-190
130-150
210-230
205-225
165-185
245-265
240-260
200-220
285-305
280-300
240-260
260-280
255-275
250-270
280-300
275-295
270-290
295-315
290-310
285-305
315-335
310-330
305-325
335-355
330-350
325-345
Note: dP pressure drops apply to standard coils, and cupro-nickel ground water coils have higher pressure drops
17
EV 580/581
Loop
EWT
15
20
25
30
35
45
50
60
70
Loop
EWT
40
50
60
70
75
80
85
90
95
Loop
GPM
14
15
16
14
15
16
14
15
16
14
15
16
14
15
16
9
10
15
9
10
15
9
10
15
9
10
15
Loop
GPM
9
10
15
9
10
15
9
10
15
9
10
15
14
15
16
14
15
16
14
15
16
14
15
16
14
15
16
dP
ft
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
5.8
6.9
11.3
5.8
6.9
11.3
5.8
6.9
11.3
5.8
6.9
11.3
dP
ft
5.8
6.9
11.3
5.8
6.9
11.3
5.8
6.9
11.3
5.8
6.9
11.3
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
9.9
11.3
12.9
dP
psi
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
2.5
3
4.9
2.5
3
4.9
2.5
3
4.9
2.5
3
4.9
dP
psi
2.5
3
4.9
2.5
3
4.9
2.5
3
4.9
2.5
3
4.9
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
4.3
4.9
5.6
MBTU/hr
24.2
24.5
24.7
26.7
27.0
27.3
29.2
29.5
29.8
31.7
32.0
32.3
34.1
34.5
34.8
37.5
37.9
39.5
39.9
40.3
42.0
44.7
45.1
47.0
49.4
49.9
52.0
Heating @ 68oF EAT
First Stage @ 1400 cfm
Suct
Head
KW
COP
Press
Press
2.5
3.0
46-56
255-275
2.5
3.0
47-57
260-280
2.5
3.1
48-58
265-285
2.6
3.1
56-66
260-280
2.6
3.2
57-67
265-285
2.6
3.2
58-68
270-290
2.7
3.3
66-76
270-290
2.8
3.3
67-77
275-295
2.8
3.4
68-78
280-300
2.8
3.4
75-85
280-300
2.9
3.5
76-86
285-305
2.9
3.5
77-87
290-310
3.0
3.6
85-95
290-310
3.0
3.6
86-96
295-315
3.0
3.7
87-97
300-320
3.1
3.8
100-110 305-325
3.2
3.8
101-111 305-325
3.2
3.9
106-116 310-330
3.7
3.9
110-120 310-330
3.8
4.0
111-121 315-335
3.8
4.1
116-126 320-340
3.5
4.2
129-139 325-345
3.5
4.3
130-140 330-350
3.6
4.4
135-145 335-355
3.7
4.5
149-159 345-365
3.8
4.6
150-160 350-370
3.8
4.7
155-165 355-375
MBTU/hr
55.0
55.6
56.7
52.6
53.1
54.2
50.2
50.7
51.7
47.7
48.2
49.2
47.5
48.0
48.4
46.2
46.7
47.2
45.0
45.5
45.9
43.8
44.2
44.7
42.5
43.0
43.4
COOLING @ 80oF DB/67oF WB
First Stage @ 1400 cfm
Suct
Head
KW
EER
Press
Press
1.5
31.6
131-141 145-165
1.5
32.2
130-140 140-160
1.4
34.6
129-139 130-150
1.8
27.9
132-142 180-200
1.8
28.5
131-141 175-195
1.7
30.6
130-140 165-185
2.1
24.3
133-143 215-235
2.0
24.8
132-142 210-230
1.9
26.6
131-141 200-220
2.3
20.6
134-144 245-265
2.3
21.0
133-143 240-260
2.2
22.6
132-142 230-250
2.3
20.2
134-144 255-275
2.3
20.6
133-143 250-270
2.3
21.0
132-142 245-265
2.5
18.3
134-144 270-290
2.4
18.6
133-143 265-285
2.4
19.0
132-142 260-280
2.6
16.3
135-145 285-305
2.6
16.6
134-144 280-300
2.5
17.0
133-143 275-295
2.7
14.3
135-145 305-325
2.7
14.6
134-144 300-320
2.7
14.9
133-143 295-315
2.9
12.4
136-146 320-340
2.8
12.6
135-145 315-335
2.8
12.9
134-144 310-330
Note: dP pressure drops apply to standard coils. Cupro-nickel ground water coils have higher pressure drops.
18
MBTU/hr
37.2
37.6
37.9
40.4
40.8
41.2
43.6
44.1
44.5
46.8
47.3
47.8
50.1
50.6
51.1
54.2
54.8
57.1
57.3
57.9
60.3
63.5
64.1
66.8
69.7
70.4
73.3
Second Stage @ 1800 cfm
Suct
KW
COP
Press
4.1
2.9
47-57
4.1
2.9
48-58
4.1
3.0
49-59
4.2
3.0
66-76
4.3
3.1
67-77
4.3
3.1
68-78
4.4
3.2
64-74
4.4
3.2
65-75
4.4
3.2
66-76
4.5
3.3
73-83
4.5
3.3
74-84
4.5
3.3
75-85
4.6
3.4
81-91
4.7
3.4
82-92
4.7
3.5
83-93
4.8
3.6
91-101
4.8
3.6
92-102
4.9
3.7
99-109
4.9
3.7
100-110
5.0
3.7
101-111
5.1
3.8
108-118
5.2
3.9
117-127
5.2
4.0
118-128
5.4
4.1
125-135
5.5
4.2
134-144
5.5
4.2
135-145
5.6
4.3
142-152
Head
Press
265-285
270-290
275-295
275-295
280-300
285-305
285-305
290-310
295-315
300-320
305-325
310-330
310-330
315-335
320-340
325-345
330-350
340-360
335-355
340-360
350-370
360-380
365-385
375-395
380-400
385-405
395-415
MBTU/hr
66.7
67.4
68.7
64.5
65.2
66.5
62.4
63.0
64.3
60.2
60.8
62.1
60.3
60.9
61.5
59.2
59.8
60.4
58.1
58.7
59.3
57.0
57.6
58.2
55.9
56.5
57.0
Second Stage @ 1800 cfm
Suct
KW
EER
Press
2.9
20.9
119-129
2.9
21.4
118-128
2.7
23.0
115-125
3.2
19.2
122-132
3.2
19.6
121-131
3.1
21.1
118-128
3.6
17.5
124-134
3.5
17.8
123-133
3.4
19.2
120-130
3.9
15.8
127-137
3.9
16.1
126-136
3.7
17.3
123-133
3.9
16.0
125-135
3.8
16.3
124-134
3.8
16.7
123-133
4.0
15.1
127-137
4.0
15.4
126-136
3.9
15.7
125-135
4.2
14.1
128-138
4.1
14.4
127-137
4.1
14.7
126-136
4.3
13.2
130-140
4.3
13.5
129-139
4.3
13.8
128-138
4.5
12.3
131-141
4.5
12.5
130-140
4.4
12.8
129-139
Head
Press
160-180
155-175
140-160
195-215
190-210
175-195
230-250
225-245
210-230
265-285
260-280
245-265
270-290
265-285
260-280
285-305
280-300
275-295
305-325
300-320
295-315
325-345
320-340
315-335
340-360
335-355
330-350
XVI. Fan Performance Data
UNIT SIZE
EV 380/381
EV 480/481
EV 580/581
Low (G)
520
740
800
Medium (Y)
910
1295
1400
Medium-High (Y2)
1180
1680
1800
High (W2, E)
1300
1800
1900
Physical Data
Vara 2 Plus
48
58
Compliant Scroll
Thermostatic
High Density
4
4
5
10x8
Variable Speed ECM
3/4
1.0
1/150 HP
55
340
350
365
38
Compressor
Expansion Device
Air Coil Type
No. of Air Coil Rows
Fan Wheel (dia. x width)
Fan Motor Type
Fan Motor (HP)
Desuperheater Pump
Transformer (VA)
Weight (lbs)
XVII. Dimensions – EV Vertical Top Discharge Models
A
B
C
E
F
Access Panels
3.0"
0.88" Dia.
Knockouts
G
H
In from Ground
Loop
Condensate
Drain
Out to Ground
Loop
0.88" Dia.
Knockout
Out to Water
Heater
In from Water
Heater
Desuperheater
W
D
Model
Vara 38-48 Vxxx
Vara 58-68 Vxxx
Top-Discharge
Dimensions
H
W
D
Blower
Opening
A
B
Water
Inlets
Outlets
Cond.
Drain
Filter Size*
(Inches)
C
Other
Dimensions
E
F
G
I
53.1 27.0 31.1 12.00 10.25 1.0 FPT 1.0 FPT 1.0 FPT
21-5/8 x 29 (top load)
0.6 21.9 1.3 28.5 7.0
53.1 27.0 31.1 12.00 10.25 1.0 FPT 1.0 FPT 1.0 FPT
26-5/8 x 29 (top load)
0.6 26.9 1.3 28.5 7.0
*Note: Filter Rack extends 1-1/4” outward from the cabinet.
19
XVIII. Electrical Data (all HCAR-type circuit breaker per NEC)
Model
380/381
480/481
580/581
Voltage
Phase
Frequency (Hz)
208/230-1, 60
208/230-3, 60
208/230-1, 60
208/230-3, 60
208/230-1, 60
208/230-3, 60
Compressor
RLA
LRA
16.7
82
11.2
58
21.2
96
13.5
88
25.6
118
17.6
123
Blower
HP
FLA
3/4
6.8
3/4
6.8
3/4
6.8
3/4
6.8
1
9.1
1
9.1
Without FlowCenter
Total
Min.
Max
FLA
Amp.
Fuse
---18.0
20.8
30
---20.3
23.7
35
---26.7
31.1
45
FlowCenter
HP
FLA
1/3
3.6
--1/3
3.6
--1/2
5.4
---
Total
FLA
27.1
-31.6
-40.1
--
With FlowCenter
Min.
Max Fuse/
Amp.
Ckt Brk*
31.3
45
--36.9
55
--46.6
70
---
Correction Factors
EV Entering Air Temperature
ENTERING
AIR TEMP
60oF DB
65oF DB
70oF DB
o
75 F DB/63oF WB
80oF DB/67oF WB
85oF DB/71oF WB
HEATING
BTU/hr
KW
1.04
0.96
1.02
0.98
1.00
1.00
0.97
1.03
0.93
1.07
---
COOLING
BTU/hr
KW
--0.70
0.73
0.79
0.83
0.90
0.92
1.00
1.00
1.05
1.04
Ground Side Flow Rates
NOMINAL
GPM
50%
55%
60%
65%
70%
80%
90%
100%
110%
120%
130%
140%
150%
20
HEATING
BTU/hr
KW
0.90
0.97
0.91
0.97
0.92
0.98
0.93
0.98
0.94
0.98
0.96
0.99
0.98
0.99
1.00
1.00
1.02
1.00
1.04
1.00
1.06
1.01
1.07
1.01
1.08
1.02
COOLING
BTU/hr
KW
0.97
1.05
0.97
1.05
0.98
1.04
0.98
1.04
0.98
1.03
0.99
1.02
0.99
1.01
1.00
1.00
1.01
0.99
1.02
0.98
1.02
0.98
1.03
0.97
1.03
0.96
EV Airflow
NOMINAL
CFM
80%
85%
90%
95%
100%
105%
110%
HEATING
BTU/hr
KW
0.92
1.04
0.95
1.03
0.97
1.02
0.99
1.01
1.00
1.00
1.01
0.99
1.02
0.98
COOLING
BTU/hr
KW
0.96
0.97
0.97
0.98
0.98
0.98
0.99
0.99
1.00
1.00
1.01
1.01
1.02
1.02
XIX. Water Coil Pressure Drop Ratings (Pure Water)*
Flow
GPM
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
20
22
24
26
28
30
32
34
EV17
EH17
EV27
EH27
EV37
EH37
EV38
EH38
EV47
EH47
EV48
EH48
0.9
0.9
1.5
2.2
3.5
3.9
5.2
6.5
-
0.8
1.2
1.6
2.4
2.8
3.6
4.4
5.2
6.4
7.6
-
0.8
1.2
1.6
2.4
2.8
3.6
4.4
5.2
6.4
7.6
-
0.8
1.2
1.6
2.4
2.8
3.6
4.4
5.2
6.4
7.6
-
1.6
2.0
2.5
3.1
3.8
4.3
4.8
6.0
7.5
9.4
-
1.6
2.0
2.5
3.1
3.8
4.3
4.8
6.0
7.5
9.4
-
EV57
EH57
EV58
EH58
EV67
EH67
EV68
EH68
GH87
GH110
3.8
4.6
5.3
6.1
7.0
9.0
10.2
-
2.3
2.8
3.3
3.8
4.3
4.9
5.6
6.3
7.0
-
2.3
2.8
3.3
3.8
4.3
4.9
5.6
6.3
7.0
-
0.8
0.9
1.0
1.2
1.5
1.7
2.0
2.3
2.6
2.9
3.3
0.8
0.9
1.0
1.2
1.5
1.7
2.0
2.3
2.6
2.9
3.3
dP PSIG
3.8
4.6
5.3
6.1
7.0
9.0
10.2
-
*Note: dP Pressure Drops apply to standard coils, and cupro-nickel ground water coils have higher pressure drops.
Note: Head Loss = Pressure Drop in PSI x 2.31.
21
Wiring Diagram, Vara 2 Plus [E/G(V,H)xxx-x-Vxxx]
9GRN
6GRN/BLU
Heat Pump Thermostat
Y2 E R G O Y Aux L C
Optional
Slide-In Heater
1
2
3
4
5
DC
Blower
Motor
9 10 11 12 13 14 15 16
1 2 3 4 5 6 7 8
X W2 E
3GRN
2RED
12WHT/
BLU
8BLK
Equipment
Ground
R
A B C D A B C D A B C D
W2 E
1BLK
2GRN/
RED
10WHT
DO
4RED
7YEL
Wht
5WHT/BLU
Brn
Wht
TSL
3WHT/RED
2GRN/RED
Wht
Blu
1ORG
Blu
Y2
LOW
Y E W2
HIGH
MED
+
1-Phase
Power
-
Adjust
E R G O Y W2 L X
24V Transf
PWR
SP
J1
Red
X
Blu
WHT
208V Yel
F1
J2
R
BLK
J3
11BLU
X
ASC
RED
R
Blu
X
SA
Controller
RC
O
X
X
Blu
PA
LP/
FP
DT
M1
G
Blu
Yel
M1
HP
BLK
10VA Maximum
External Connected
Load (24Vac)
Blu
Blu
Blk
Org
VB
3
1
2
F2
HP
LP / FP
VR
COMPRESSOR
Desuperheater
Pump (Optional)
To PumpPAK
(Optional)
Wht
S
C
HL
Blu
Blk
Vara 2+ Heat Pump
Electrical Diagram
80-0040,K ECO 2011-134
R
Blk
Blu
FREEZE
STAT
(Optional)
BLU
RED
Blk
Factory Low Voltage
Factory Line Voltage
Field Line Voltage
Field Low Voltage
Three Phase
M1
B R
U D
L
2
B
K
L
1
L3
COMPRESSOR
DO
DT
F1
F2
FP
HL
HP
Dry Contact Output
Discharge Thermostat
Fuse, Transformer
Fuse, Desuperheater
Freeze Protection
High-Temp Limit
High-Press Switch
LP
M1
PA
RC
SA
Low-Press Switch
Contactor
Plug, Accessory
Run Capacitor
Start Assist (Some
Single Ph Models)
SP Spare Fuse
VR Valve, Reversing
VB Compressor Bypass
Valve (engergize for Y2)
TSL Third Stage Latch
J1 Remove for Hydronic
J2 Ties W2 to E
J3 Overflow Protection
BLOWER SPEEDS
A = 68 or 78 Series
B = 58 Series
C = 48 Series
D = 38 Series
+ = Incr CFM 10%
- = Decr CFM 10%
BLOWER MOTOR CONTROL WIRES
1 – 11BLU (X)
2 – 10WHT (W2)
3 – 12WHT/BLU (X)
4 – 2GRN/RED (Md)
5 – 3WHT/RED (Lo)
6 – 7YEL (Y)
7 – 10ORG (+/-)
11 – 5WHT/BLU (Hi)
12 – 4RED (R)
13 – 8BLK (E)
14 – 6GRN/BLU (Y2)
15 – 9GRN (G)
XXI. TROUBLESHOOTING GUIDE FOR LOCKOUT CONDITIONS
If the heat pump goes into lockout on a high or low
pressure switch, the cause of the lockout can be narrowed
down by knowing the operating mode and which pressure
switch the unit locked out on. The following table will
help track down the problem once this information is
CONDITION
AC power applied
AC power applied
AC power applied
Run cycle complete
LOW PRESSURE
INDICATOR
Heating or Cooling –
before Y1 call
INDICATOR LIGHTS
PWR ASC LP
HP
COMMENTS
Off
Off
Off
Off Blown fuse or power removed.
X
X
ASC indicator on for 4' 35" on power initialization.
X
Power applied - unit running or waiting for a call to run.
X
X
ASC indicator ON for 70 to 130 seconds after compressor shutdown.
X
X
Flash
X
X
X
-Check if Low Pressure switch is open.
-Check electrical connections between Low Pressure switch and Controller.
-Loss/lack of flow through ground-side heat exchanger.
-Low fluid temperature operation in ground-side heat exchanger.
-Freezing fluid in ground-side heat exchanger (lack of antifreeze).
-Dirty (fouled) ground-side heat exchanger (on ground water systems).
-Low ambient temperature at the heat pump.
-Undercharged / overcharged refrigerant circuit.
-Expansion valve / sensing bulb malfunction.
-Excessive low return air temperature.
-Freezing air coil (dirty air filter or air coil, undercharged refrigerant circuit)
-Missing blower compartment access panel.
-Loss-lack of airflow (dirty filter, closed vents, blower failure, restricted
ductwork, etc.)
-Low return air temperature.
-Low ambient temperature at the heat pump.
-Undercharged / overcharged refrigerant circuit.
-Expansion valve / sensing bulb malfunction.
-Excessively low fluid temperature in the ground side heat exchanger.
Heating – during Y1 call
X
Cooling – during Y1 call
HIGH PRESSURE
INDICATOR
Heating or Cooling –
before Y1 call
Cycle Blink
On
and
Off
every
few
min.
X
X
X
X
X
X
X
X
Heating – during Y1 call
Cooling – during Y1 call
known. Note – A lockout condition is a result of the
heat pump shutting itself off to protect itself, never bypass
the lockout circuit. Serious damage can be caused by the
system operating without lockout protection.
-Check if High Pressure switch is open.
-Check electrical connections between High Pressure switch and Controller.
-Missing blower compartment access panel.
-Loss/lack of airflow (dirty filter, closed vents, blower, restricted ductwork,
etc.)
-High return air temperatures.
-Overcharged refrigerant circuit.
-Expansion valve / sensing bulb malfunction.
-Dirty (fouled) air coil.
-Loss/lack of flow through the ground-side heat exchanger.
-High fluid temperature in the ground-side heat exchanger.
-Dirty (fouled) ground-side heat exchanger (on ground water systems).
-Overcharged refrigerant circuit.
-Expansion valve / sensing bulb malfunction.
23
XXII. TROUBLESHOOTING GUIDE FOR UNIT OPERATION
PROBLEM
POSSIBLE CAUSE
Blown Fuse/Tripped Circuit
Breaker
Blown Fuse on Controller
Broken or Loose Wires
Voltage Supply Low
Low Voltage Circuit
Entire unit
does not run Room Thermostat
Interruptible Power
Dirty Filter
Thermostat Improperly Set
Unit will not
Defective Thermostat
operate on
Incorrect Wiring
“heating”
Blower Motor Defective
Dirty Air Filter
Evaporator Airflow
(air coil) ices
over in
cooling mode Blower Speed Set too Low
Low Air Temperature
Room Thermostat
Wiring
Blown Fuse
High or Low Pressure Controls
Voltage Supply Low
Blower motor
runs but
Low Voltage Circuit
compressor
does not, or
compressor
short cycles Compressor Overload Open
Compressor Motor Grounded
Compressor Windings Open
Seized Compressor
Room Thermostat
Unit short
cycles
Wiring and Controls
Compressor Overload
Continued on next page.
24
CHECKS AND CORRECTIONS
Replace fuse or reset circuit breaker. (Check for correct size fuse or circuit breaker.)
Replace fuse on controller. (Check for correct size fuse.)
Replace or tighten the wires.
If voltage is below minimum voltage on data plate, contact local power company.
Check 24-volt transformer and fuse for burnout or voltage less than 18 volts.
Set thermostat on “Cool” and lowest temperature setting, unit should run. Set thermostat on
“Heat” and highest temperature setting, unit should run. If unit does not run in both cases, the
room thermostat could be faulty or incorrectly wired. To prove faulty or miswired thermostat,
disconnect thermostat wires at the unit and jumper between “R”, “Y1” and “G” terminals and unit
should run. Replace thermostat with correct heat pump thermostat only. A substitute may not
work properly.
Check incoming supply voltage.
Check filter. Clean or replace if found dirty.
Is it below room temperature? Check the thermostat setting.
Check thermostat operation. Replace if found defective.
Check for broken, loose, or incorrect wires.
Refer to Section XVI for blower motor troubleshooting. If it does not operate the compressor will
go off on high head pressure.
Check filter. Clean or replace if found dirty.
Lack of adequate airflow or improper distribution of air. Check the motor speed and duct sizing.
Check the filter, it should be inspected every month and changed if dirty. Check for closed
registers. Remove or add resistance accordingly.
Verify blower speed jumpers are in factory settings.
Room temperatures below 65oF may ice over the evaporator.
Check setting, calibration, and wiring.
Check for loose or broken wires at compressor, capacitor, or contactor.
Replace fuse or reset circuit breaker. (Check for correct size fuse or circuit breaker.)
The unit could be off on the high or low-pressure cutout control. Check water GPM, air CFM and
filter, ambient temperature and loss of refrigerant. If the unit still fails to run, check for faulty
pressure controls individually. Replace if defective.
If voltage is below minimum voltage specified on the data plate, contact local power company.
Check voltage at compressor for possible open terminal.
Check transformer and fuse for burn out or voltage less that 18 volts. With a voltmeter, check
signal from thermostat at Y1 to X, M1 on controller to X, check for 24 volts across the
compressor contactor. Replace component that does not energize.
In all cases an “internal” compressor overload is used. If the compressor motor is too hot, the
overload will not reset until the compressor cools down.
Internal winding grounded to the compressor shell. Replace the compressor. If compressor
burnout, replace inline filter drier.
Check continuity of the compressor windings with an ohmmeter. If the windings are open, replace
the compressor.
Try an auxiliary capacitor in parallel with the run capacitor momentarily. If the compressor still
does not start, replace it.
Improperly located thermostat (e.g. near kitchen, inaccurately sensing the comfort level in living
areas). Check anticipator setting. Should be 1.0 or 1.2.
Loose wiring connections, or control contactor defective.
Defective compressor overload, check and replace if necessary. If the compressor runs too hot, it
may be due to an insufficient refrigerant charge.
PROBLEM
POSSIBLE CAUSE
Unit does not Reversing Valve does not Shift
cool (Heats
Only)
Room Thermostat
Reversing Valve does not Shift,
the Valve is Stuck
Insufficient
cooling or
heating
Water
CHECKS AND CORRECTIONS
Defective solenoid valve will not energize. Replace solenoid coil.
Ensure that it is properly configured according to their own instructions for the “System Type”
they are installed on.
The solenoid valve is de-energized due to miswiring at the unit or thermostat-correct wiring.
Replace if valve is tight or frozen and will not move. Switch from heating to cooling a few times
to loosen valve.
Lack of sufficient pressure, temperature and/or quantity of water.
Unit Undersized
Water drips
from unit
Noisy
Operation
Recalculate heat gains or losses for space to be conditioned. If excessive, rectify by adding
insulation, shading, etc.
Loss of Conditioned Air by Leaks Check for leaks in ductwork or introduction of ambient air through doors/windows.
Room Thermostat
Improperly located thermostat (e.g. near kitchen, not sensing the comfort level in living areas).
Check anticipator setting (Should be 1.0 or 1.2).
Airflow
Lack of adequate airflow or improper distribution of air. Check the motor speed and duct sizing.
Check the filter, it should be inspected every month and cleaned if dirty. Remove or add resistance
accordingly.
Refrigerant Charge
Low on refrigerant charge causing inefficient operation. Adjust only after checking CFM,GPM,
and inlet/outlet temperatures.
Compressor
Check for defective compressor. If discharge pressure is too low and suction pressure is too high,
compressor is not pumping properly. Replace compressor.
Desuperheater
The desuperheater circuit (in-line fuse) should be disconnected during cold weather to allow full
heating load to the house.
Reversing Valve
Defective reversing valve creating bypass of refrigerant from discharge to suction side of
compressor. When it is necessary to replace the reversing valve, wrap it with a wet cloth and
direct the heat away. Excessive heat can damage the valve.
Unit not Level
Level vertical units.
Condensate Drain Line Kinked or Clean condensate drain. Make sure external condensate drain is installed with adequate drop and
Plugged
pitch.
Compressor
Make sure the compressor is not in direct contact with the base or sides of the cabinet. Cold
surroundings can cause liquid slugging, increase ambient temperature.
Blower and Blower Motor
Blower wheel hitting the casing, adjust for clearance and alignment. Bent blower, check and
replace if damaged. Loose blower wheel on shaft, check and tighten.
Contactor
A “clattering” or “humming” noise in the contactor could be due to control voltage less than 18
volts. Check for low supply voltage, low transformer output, or transformer tap setting. If the
contactor contacts are pitted or corroded or coil is defective, repair or replace.
Rattles and Vibrations
Check for loose screws, panels, or internal components. Tighten and secure. Copper piping could
be hitting the metal surfaces. Carefully readjust by bending slightly. Check that hard plumbing is
isolated from building structures.
Water and Airborne Noises
Undersized ductwork will cause high airflow velocities and noisy operation. Excessive water
through the water-cooled heat exchanger will cause a squealing sound. Check the water flow,
ensuring adequate flow for good operation but eliminating the noise.
Cavitating Pumps
Purge air from ground loop system.
25
XXIII. TROUBLESHOOTING GUIDE FOR ECM BLOWER
PROBLEM
Motor rocks
slightly when
starting
Motor won’t start
•No movement
Motor rocks, but
won’t start
CHECKS AND CORRECTIONS
•This is normal start-up for ECM
•Wait for completion of ramp-up at start
•Check power at motor
•Check low voltage (24 VAC R to X) at motor
•Check low voltage connections (G, Y, W2, R, X) at motor
•Check for unseated pins in connectors on motor harness
•Test with a temporary jumper between R and G
•Check motor for a tight shaft
•Perform Moisture Check*
•Check for loose or compliant motor mount
•Make sure blower wheel is tight on shaft
Motor starts, but
runs erratically
•Varies up and
down or
intermittent
•Check line voltage for variation or “sag”
•Check low voltage connections (G, Y, W2, R, X) at motor, unseated pins in motor harness connectors
•Check out system controls, thermostat
•Perform Moisture Check*
”Hunts” or “puffs”
at high CFM
(speed)
•Does removing panel or filter reduce puffing?
Reduce restriction
Stays at low CFM
despite call for
higher speed
•Check low voltage wires and connections
•Verify fan is not in delay mode; wait until delay complete
•”R” missing/not connected at motor
Stays at high CFM
•Verify fan is not in delay mode; wait until delay complete
•”R” missing/not connected at motor
•Power to the unit must be reset to enable the new settings
•Verify fan is not in delay mode; wait until delay complete
•”R” missing/not connected at motor
Blower won’t
change CFM after
adjusting the speed
control setting.
Blower won’t shut
off
Excessive noise
Air noise
Noisy blower or
cabinet
•Current leakage from controls into G, Y, or W?
•Determine if it’s air noise, cabinet, duct or motor noise
•High static creating high blower speed?
Does removing filter cause blower to slow down? Check filter
Use low-pressure drop filter
Check/correct duct restrictions
•Check for loose blower housing, panels, etc.
•High static creating high blower speed?
Check for air whistling through seams in ducts, cabinets, or panels
Check for cabinet/duct deformation
*Moisture Check
•Connectors are oriented as recommended by equipment manufacturer
•Check for low airflow (too much latent capacity)
•Check and plug leaks in return ducts, cabinet
•Is condensate drain plugged?
•Check for undercharged conditions
**Comfort Check
•Check proper airflow settings
•Set low continuous-fan CFM
•Low static pressure for low noise
•Thermostat in good location?
26
XXIV. ADDITIONAL FIGURES
Figure 3 – Electrical Diagram for ECONAR Intelligent Slide-In-Heater
IN
Out
Pressure/Temperature
(P/T) Ports
PumpPAK
To/From
Closed Loop
Figure 4 – Ground Loop Water Plumbing
27
From Bladder-Type
Pressure Tank
Shutoff
Valves
Boiler
Drains
Strainer
IN
Visual Flow
Meter
Solenoid
Valve
Pressure/Temperature
(P/T) Ports
Out
Flow Control
Valve
Discharge
Figure 5 – Ground Water Plumbing
COLD
HOT
1/2" or 3/4"
Copper Pipe
Air Vent
1/2" Copper Pipe
Desuperheater Tee
Shutoff Valves
Drain (Hang Down)
Figure 6 – Preferred Desuperheater Installation
28
COLD
Check Valve
HOT
1/2" or 3/4"
Copper Pipe
Air Vent
Drain (Hang Down)
1/2" Copper Pipe
Shutoff Valves
Figure 7 – Alternate Desuperheater Installation
29
Greenville, IL & Mitchell, SD
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90-1202 Rev B (2011-008) | 2012 Enertech Global, LLC. | All Rights Reserved