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ABOUT THE HEAT PUMP
(Dual Fuel Models Only)
Your heat pump is a unique, all weather comfort-control appliance
that will heat and cool your building year round and provide
energy saving comfort. It’s an unknown fact that heat is always
in the air, even when the outside temperature is below freezing.
The heat pump uses this basic law of physics to provide energy
saving heat during the winter months.
In colder temperatures, the heat pump performs like an air
conditioner run in reverse. Available heat energy outside the
building is absorbed by the refrigerant and exhausted inside.
This efficient process means you only pay for “moving” the heat
from the outdoors to the indoor area. You do not pay to generate
the heat, as is the case with more traditional furnace designs.
During summer, the heat pump reverses the flow of the heat-
absorbing refrigerant to become an energy-efficient, central air
conditioner. Excess heat energy inside the home is absorbed
by the refrigerant and exhausted outside the building.
OPERATING INSTRUCTIONS
A thermostat with fossil fuel back-up heat capability is required
to operate the Dual Fuel iHybrid™ heat pump system. The
thermostat should be mounted about 5 feet above the floor on
an inside wall and not on an outside wall or other location where
its operation may be adversely affected by radiant heat from
fireplaces, sunlight, or lighting fixtures, and convective heat from
warm air registers or electrical appliances.
Thermostat styles vary. Some models will not include the AUTO
mode and others will have the AUTO in place of the HEAT
and COOL. Others may include all three. Please refer to the
thermostat’s User Manual for detailed programming instructions.
NOTE: If the temperature level is re-adjusted, or the system
mode is reset, the fan and compressor in the outdoor unit
may not start immediately. A protective timer circuit holds the
compressor and the outdoor fan off for approximately 5 minutes
following a previous operation or the interruption of the main
electrical power.
Cooling Operation (1 or 2 Stage Operation)
1. Set the thermostat system mode to COOL and the thermostat
fan mode to AUTO. See Figure 1.
2. Set the thermostat temperature selector to the desired
temperature level. The outdoor fan, compressor, and
indoor blower will all cycle on and off to maintain the indoor
temperature at the desired cooling level.
NOTE: If Stage 1 cool does not satisfy the thermostat demand,
stage 2 cool will energize. The outdoor compressor and indoor
blower will ramp to high speed.
Heating Operation - Heat Pump Mode
1. Set the thermostat’s system mode to HEAT or AUTO and
change the fan mode to AUTO. See Figure 1 (pg 3).
2. Set the temperature selector to the desired temperature level.
The compressor, outdoor fan, and blower motor will cycle
on and off to maintain the indoor temperature at the desired
heating level.
NOTES:
• If Stage 1 heat does not satisfy the thermostat demand, stage
2 heat will energize. The outdoor compressor and indoor
blower will ramp to high speed.
• On some thermostats, if the heating load on the conditioned
space is not met in a normal period of time or the difference
between the thermostat set point and room temperature is
large, the heat pump will automatically shut off and the gas
heat will operate until the thermostat demand for heat is met.
Emergency Heat - Gas Heat mode
Heat pump thermostats include a system mode called EM HT or
AUX HT, etc. This is a back-up heating mode that should only
be used if a problem is suspected. With the mode set to EM HT,
etc., the compressor and outdoor fan will be locked off and the
gas furnace will be used as a source of heat. Sustained use of
gas heat in place of the heat pump will result in an increase in
this utility cost. Refer to the thermostat manual for more info.
Defrost Operation
During cold weather heating operation, the outdoor unit will
develop a coating of snow and ice on the heat transfer coil.
This is normal and the unit will defrost itself. This unit features
Demand Defrost that monitors ambient and coil temperatures
to regulate the defrost function accordingly.
At the beginning of the defrost cycle, both the outdoor condenser
fan and compressor will turn off. After approximately 30 seconds,
the compressor will turn on and begin to heat the outdoor coil
causing the ice and snow to melt.
During the defrost period, the gas funace will energize and
produce warm air to offset the heat pump operation while in its
reverse cycle. Initially the air out of the supply registers may
be slightly cooler since the heat pump has reversed its cycle
and is now in the cooling mode to aide in the defrosting of the
outdoor coil. The air will rise in temperature as the gas furnace
continues to operate and the blower speed increases.
NOTE: While the ice and snow is melting, some steam may
rise from the outdoor unit as the warm coil causes the melting
frost to evaporate. When defrost is completed, the outdoor
fan motor will start, and the compressor will turn off again. In
approximately 30 seconds the compressor will start up again
and continue normal operation. The gas heat will shut down at
the end of the defrost cycle.
Automatic Heat Pump Operation (Cooling &
Heating)
1. Set the thermostat system mode to AUTO and the thermostat
fan mode to AUTO. See Figure 1 (page 3).
2. Set the thermostat’s temperature selector to the desired
heating and cooling temperature level(s). The outdoor unit and
the indoor blower will then cycle on and off in either the heating
or cooling mode of operation as required to automatically
maintain the indoor temperature within the desired limits.
Continuous Indoor Blower Operation
The continuous indoor blower operation is typically used to
circulate the indoor air to equalize a temperature imbalance
due to a solar load, cooking, or fireplace operation.
Set the thermostat fan mode to ON (see Figure 1). The indoor
blower will start immediately and will run continually until the fan
switch is reset to AUTO. NOTE: On some thermostat models
the setting may be called CONT.
Continuous indoor blower
operation can be obtained with the thermostat system switch
set in any position, including OFF.
System Shutdown
Set the thermostat system mode to OFF and the thermostat fan
mode to AUTO. See Figure 1. NOTE: The system will not operate,
regardless of the thermostat temperature selector’s setting.
DUAL FUEL UNITS - GAS HEAT / ELECTRIC HEAT PUMP