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Hi, our Vitodens 100 Combi was working fine until I removed a radiator whilst decorating. The radiator was off for 2 days during which time I turned the CH dial off, the DHW was still on. After re-fitting the radiator the water pressure had dropped to 0 Bar. I brought the pressure back up to 1.2 Bar in the normal way.
Now, on CH or DHW demand the boiler will not ignite but shows an F9 Fault code.
In all cases, the pump starts, but nothing else happens until about a minute later when the F9 code appears. Re-setting it does not solve anything.
I have checked that the air pressure switch operates ok and that the fan is free to rotate, so I concluded that the fan is not getting a signal to start.
The main fan connector is seeing 240v but the small 3 wire connector is reading 8.5v and 1.0v measured between each outer terminal and the centre. See photo attached.
Does anyone know if this sounds OK or could this be the problem?
Under the F9 fault code the manual says "check the fan, check the fan cables, check the fan control" What is the fan control and and how do you check that?
Any suggestions gratefully received.
Many thanks in advance.
UPDATED 1/5/24
I read somewhere that with the main 240V plug in place but the small plug disconnected as shown, the fan should run at full speed. Does anyone know if that is correct?
In our case it does not run at all, so I guess it means that the fan is faulty rather than the circuit board.
Now, on CH or DHW demand the boiler will not ignite but shows an F9 Fault code.
In all cases, the pump starts, but nothing else happens until about a minute later when the F9 code appears. Re-setting it does not solve anything.
I have checked that the air pressure switch operates ok and that the fan is free to rotate, so I concluded that the fan is not getting a signal to start.
The main fan connector is seeing 240v but the small 3 wire connector is reading 8.5v and 1.0v measured between each outer terminal and the centre. See photo attached.
Does anyone know if this sounds OK or could this be the problem?
Under the F9 fault code the manual says "check the fan, check the fan cables, check the fan control" What is the fan control and and how do you check that?
Any suggestions gratefully received.
Many thanks in advance.
UPDATED 1/5/24
I read somewhere that with the main 240V plug in place but the small plug disconnected as shown, the fan should run at full speed. Does anyone know if that is correct?
In our case it does not run at all, so I guess it means that the fan is faulty rather than the circuit board.
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