Operating instructions

12
Low Ambient Heat Pump Lock Out
All heat pumps are constrained to operation at a temperature range
that is determined by outside conditions. Since all heat pumps lose
their efciency at low outside ambient temperatures, the Dometic
heat pump has a lock out feature that prevents heat pump mode
of operation when temperatures fall below 30 °F. If you have the
system set in the Auto Mode the fan will be turned OFF. Only the
fan will remain ON if the fan setting is set at Low or High, however
the compressor will not run and there will be no heat function below
30°F.
Power Interruption
In the event the power to the air conditioner or control is interrupted,
the system will restart with the previous set points once power is
restored.
LCD Error Code
When the system determines that one of the faults listed below has occurred an error
code will be displayed in the LCD.
Error Code:
E1 Loss of communication between the Single Zone LCD thermostat and the mod-
ule board. LCD will cycle between E1 and the previous mode setting. System
will shut down.
E2 Open circuit or out of range Indoor Temperature Sensor. Heating and cooling
operation will be locked out. Fan operation can continue to operate.
E3 Shorted Indoor Temperature Sensor. Heating and cooling operation will be
locked out. Fan operation can continue to operate.
E4 Open circuit or out of range Outdoor Temperature Sensor (select models). Heat
Pump operation will be locked out. Air Conditioner, Fan and Furnace operation
can continue to operate.
E5 Open circuit or out of range Freeze Sensor. Air conditioner mode of operation
will be locked out. Furnace, heat strip, heat pump and fan mode of operation can
continue to operate but displays the last temperature set-point.