Truma CP plus Operating Instructions Manual page 26

Troubleshooting guide
Fault Cause
code
E 112 H, Flame out or not detected,
E 121 H, Flame unstable during operation,
E 122 H, Gas supply interrupted
E 202 H,
E 211 H,
E 212 H
E122H Lack of fuel due to low tank level, tank is empty and / or
vehicle is on a slope
W 255 H Heater has no 12 V power supply
No connection between heater and control panel
W 301 H, 12 V power supply faulty (overvoltage)
W 417 H
W 302 H, 12 V power supply faulty (low voltage)
W 418 H
W 303 H, Risk of low voltage�
W 411 H Battery voltage too low < 10�4 V
W 401 H Hot water mode with empty water container
W 402 H Warning Air overheat condition
Not all warm air ducts are connected
Warm air outlets blocked
Circulated air intake blocked
W 407 H 230 V power supply faulty
26 EN
Remedy
Check that the gas supply has the correct operating pressure
(see Fault catalogue, gas supply)
Fill tank with fuel and then fill the fuel line (see operating instruc-
tions / initial start-up)
Check the 12 V power supply at the appliance input; to test, discon-
nect the power supply unit and the solar system from the on-board
power supply
Check the control panel cable and make sure there is connection be-
tween the heater and the control panel
Check the 12 V power supply at the appliance input; to test, discon-
nect the power supply unit and the solar system from the on-board
power supply
Charge battery and check contacts, replace old battery
Check the function with the motor running, check the power supply
unit or other batteries� Charge battery and check contacts, replace
old battery
Switch heater off and allow it to cool�
Fill the water container with water
Make sure that all warm air ducts are connected to the heater
Check whether the warm air ducts are damaged or kinked
Remove the blockage in the circulated air intake and ensure that the
installation space is sufficiently ventilated
Check the 230 V power supply at the appliance input
Have an expert check the 230 V 10 AF, H fuse and replace it if
necessary
Truma CP plus
34020-01385 · 00 · 07/2022