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

42 PB
INSTALLATION
Install WRT2 Wireless Programmable Thermostat
To control the unit with a wall mounted thermostat follow
the steps below:
1. Restore power to the PTAC unit.
2. Under stand-by mode, press the “Cool” and “UP” buttons
simultaneously for three seconds, the digital displays
character“r”, and the beeper chime twice.
3. The unit is now controlled by the wall thermostat only.
4. If the accessory escutcheon kit (PDXRTB) is to be used,
install it over the existing control panel.
NOTE: The unit control panel no longer controls the unit.
To restore the control panel, press the “Cool” and “UP”
buttons simultaneously for three seconds, the digital displays
character “P”, and the beeper chime
(Figure 508) Control board with optional PDXRTB
escutcheon kit installed
(Figure 507) Control board
The unit is factory configured to display all temperatures in degrees
Fahrenheit (°F). To switch to degrees Celsius, press the “UP” and
“DOWN” buttons simultaneously for three seconds. The display will switch
to C degrees. To revert back to °F, press the “UP” and “ DOWN” buttons
simultaneously for three seconds. The display will switch toF degrees.
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 cycle the compressor on and off to maintain a comfortable room.
The compressor will cycle on anytime that the room temperature is 2 °F
above the set point. The fan will either be continuous or cycling, depends on
the “Constant Fan” selection. See Constant Fan section.
After turingn on the unit, pressing the“Heat” button willl put the unit into heating
mode.
When the “Heat” button is pressed initially the unit may call for heat pump or
electric strips (depends on different ambient temperature or DIP Switch 4
settings) to bring the room to the set point. When the roomtemperature falls
2 °
F below the set point, the unit will cycle the compressor or electric strip on. The
fan will either be continuous or cycling, depends on the “Constant
Fan” selection. See Constant Fan section. When the outdoor
coil temperature falls below 26 °F for 3 minutes, the unit will operate the
electric strip instead of heat pump. Only when the room temperature reaches
the set point and the outdoor coil temperature rises to 41 °F, the
compressor will be allowed to operate again.
After pressing the “Heat” button, adjust the set point and the unit will cycle
the electric strip on and off to maintain a comfortable room. The heater will
come on anytime that the room temperature is 2 ° F below the set point.
The fan will either continuous or cycling, depends on the “Constant Fan”
selection. See Constant Fan section.
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. 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. Dip switch 2 controls the emergency heat setting.
Constant Fa n
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” or “Auto” fan speed button.
Setting Temperature Limit
Hold "UP" and "High" fan speed buttons at the same time for 5s, digital
tube displayer will show R1-R8, default is R8. The temperature(° F)
ran
g
e as belo
w
:
R
1
:
63-86
R
2
:
6
5
-86
R
3
:
7
2
-90
R
4
:
7
2
-74
R
5
:
67-9
2
R
6
:
69-90
R
7
:
68-7
2
R
8
:
60-90