Comfort-Aire TPRG Series - Manual (Page 7)

7
HEAT PUMP UNITS
ABOUT THE HEAT PUMP
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 basic laws 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.
This unit uses environmentally friendly R-410A refrigerant.
OPERATING INSTRUCTIONS
Thermostat styles vary. Some models may not include an AUTO
heat/cool changeover mode and others will have the AUTO heat/
cool changeover in addition to HEAT & COOL. Please refer to the
thermostat’s User manual for detailed programming instructions.
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.
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. 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.
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.
NOTE:
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 electric heat will operate
until the thermostat demand for heat is met.
Emergency Heat - Electric 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 electric heat
will be used as a source of heat. Sustained use of electric 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 will monitor 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 electric heat 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 electric heat continues to operate.
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 electric heat will shut down at the end of the defrost cycle.
Automatic Cooling & Heating Operation
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.
Operating the Indoor Blower Continuously
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
(Figure 1) to ON (or CONT on some thermostat models). The indoor
blower will start immediately, and will run continually until the fan
mode is reset to AUTO.The continuous indoor blower operation can
be obtained with the thermostat system mode set in any position,
including OFF.
System Shutdown
Set the thermostat system mode (Figure 1) to OFF and the thermostat
fan mode to AUTO.
NOTE: The system will not operate, regardless
of the thermostat temperature selector’s setting.