RV air conditioner error codes
RV roof air conditioners and their thermostats show codes for communication faults, sensor failures, or freeze protection.
Advent Air
Coleman-Mach
E1
The single-zone LCD thermostat has lost its communication link with the rooftop … E2
The indoor (room) temperature sensor reads as an open circuit or its value is ou… E3
The indoor (room) temperature sensor is reading as shorted. As with E2, the ther… E4
The outdoor temperature sensor (fitted on heat-pump-equipped models) is open or … E5
The evaporator freeze sensor is open or reading out of range. Because the thermo… Er
On the Coleman-Mach multi-zone LCD thermostat, 'Er' appears in the temperature a… Heat-pump strike condition
In electric-heat (heat-pump) mode the thermostat flashes the 'Elec' segment whil… HI
The thermostat senses a temperature above the top of its measurable range. On th… LO
The thermostat is showing the room temperature it senses is below the bottom of … PTC fuse open (no power)
The digital wall thermostat contains a self-resetting PTC (resettable) fuse on i… Short-cycle / compressor delay
On the digital wall thermostat, the HVAC state segment blinks to show a built-in… Wireless comms error
On older Coleman-Mach wireless thermostat systems, the green system LED on the c…
The single-zone LCD thermostat has lost its communication link with the rooftop … E2
The indoor (room) temperature sensor reads as an open circuit or its value is ou… E3
The indoor (room) temperature sensor is reading as shorted. As with E2, the ther… E4
The outdoor temperature sensor (fitted on heat-pump-equipped models) is open or … E5
The evaporator freeze sensor is open or reading out of range. Because the thermo… Er
On the Coleman-Mach multi-zone LCD thermostat, 'Er' appears in the temperature a… Heat-pump strike condition
In electric-heat (heat-pump) mode the thermostat flashes the 'Elec' segment whil… HI
The thermostat senses a temperature above the top of its measurable range. On th… LO
The thermostat is showing the room temperature it senses is below the bottom of … PTC fuse open (no power)
The digital wall thermostat contains a self-resetting PTC (resettable) fuse on i… Short-cycle / compressor delay
On the digital wall thermostat, the HVAC state segment blinks to show a built-in… Wireless comms error
On older Coleman-Mach wireless thermostat systems, the green system LED on the c…
Dometic
E0 / EA / EE
Electronics and drive faults on the FreshJet inverter board. E0 = communication … E1
The thermostat has lost its communication link with the air conditioner/heat pum… E2
The indoor (return-air) temperature sensor is reading open-circuit or out of ran… E3
The indoor (return-air) temperature sensor is reading as shorted. As with E2, al… E4
The outdoor temperature sensor (fitted on select heat-pump models) is reading op… E5
The freeze sensor is reading open-circuit or out of range (documented on the Sin… E6
The CCC2 thermostat reads an open circuit on the optional humidity sensor (only … E7
The CCC2 has lost 120 VAC line power to all of the air conditioner power module … E8
Invalid zone configuration: the heat pump and electric heat strip DIP switches a… E9
Invalid zone configuration: the dehumidifier DIP switch and either the heat pump… EL
LIN-BUS / CI-BUS communication failure. The air conditioner has lost the data-bu… P0
The inverter control module (IPM) has detected an over-temperature or over-curre… P1
Under-voltage protection. The unit has detected the incoming supply voltage is t… P2 / P3
P2 is AC over-current protection (the unit is drawing more current than allowed)… P4 / P5 / P6 / P7
Refrigerant-circuit temperature protections. P4 = discharge tube (compressor out… P9
Compressor drive abnormal, or the compressor fails to start. The inverter drive …
Electronics and drive faults on the FreshJet inverter board. E0 = communication … E1
The thermostat has lost its communication link with the air conditioner/heat pum… E2
The indoor (return-air) temperature sensor is reading open-circuit or out of ran… E3
The indoor (return-air) temperature sensor is reading as shorted. As with E2, al… E4
The outdoor temperature sensor (fitted on select heat-pump models) is reading op… E5
The freeze sensor is reading open-circuit or out of range (documented on the Sin… E6
The CCC2 thermostat reads an open circuit on the optional humidity sensor (only … E7
The CCC2 has lost 120 VAC line power to all of the air conditioner power module … E8
Invalid zone configuration: the heat pump and electric heat strip DIP switches a… E9
Invalid zone configuration: the dehumidifier DIP switch and either the heat pump… EL
LIN-BUS / CI-BUS communication failure. The air conditioner has lost the data-bu… P0
The inverter control module (IPM) has detected an over-temperature or over-curre… P1
Under-voltage protection. The unit has detected the incoming supply voltage is t… P2 / P3
P2 is AC over-current protection (the unit is drawing more current than allowed)… P4 / P5 / P6 / P7
Refrigerant-circuit temperature protections. P4 = discharge tube (compressor out… P9
Compressor drive abnormal, or the compressor fails to start. The inverter drive …