Service and Parts Manual (2018, 2019, 2020, 2021, 2022)

28 PB
24
Digital Control Operation
Figure 29
Digital Control Panel
Cooling Mode
Emergency Heat Operation
FRP029
Pressing the “Cool” button after turn the unit on will put the unit into
cooling mode. Press “UP” or “DOWN” button to adjust the set point, the
unit will start the compressor and run appropriate frequency to maintain a
comfortable room temperature. The compressor will come on anytime that
the room temperature is 2℉above the set point. The fan will come on with
compressor.
Heating Mode
After turn on the unit, press the “Heat” button will put the unit into heating
mode.
Heat Pump Models (PVH)
When the “Heat” button is pressed initially the unit may call for electric
strips to bring the room to the set point. When the room temperature falls
2℉below the set point, the unit will turn on the compressor or electric
strip. The fan will run with compressor or electric strips. When the outdoor
ambient temperature falls below 32°F or outdoor coil temperature drops to
5℉, the unit will operate the electric strip instead of heat pump. During
heat pump mode, CPU detects the outdoor coil gets freeze, unit will go to
defrost. During the defrost operation (10min at most), there will be no
heating provide. After finishing defrost, electric heating will come on to
warm the room quickly.
In the event of a compressor failure in heat pump mode, the compressor
may be locked out to provide heat through the electric strip heater
automatically. This feature ensures that even in the unlikely event of a
compressor failure, the room temperature can be maintained until the
compressor can be serviced. If the unit still can’t run electric heater stably,
switch Dip switch 2 to OFF, it controls the emergency heat setting.
Constant Fan
Pressing the “Constant Fan” button will provide constant or cycle fan
operation in cooling or heating modes. The fan speed selection is
made by pressing either “High” or “Low” fan speed button.
OPERATION
Digital Control User Input Conguration