C1 Fan Error on Worcester Bosch 28 HE Boiler

7 Apr 2023
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United Kingdom
The C1 code is showing (error with fan) after I first first hear brief whirring-ticking, like the fan motor is trying to get going, so possibly more likely the motor as the display is normal until I attempt to run the boiler?

I realise this is possibly down to a faulty PCB, which could have been caused from electric surge if the fan itself is not faulty. The code occurred after turning the boiler on at the mains after it was off for over a week while on holiday. Can a simply manual on/off at the supply switch cause a surge and damage the PCB? Any better using the on/off switch on the boiler itself instead?

The issue has occurred before, after a kitchen refurb, so the boiler was disconnected and then when reinstalled the fan didn't work. Both now and then the boiler/fan gave about 9-10 years of good service.

Or could the fan not running for a period of time just seize up, making it difficult to get started cold?
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Usually pretty accurate and probably fan fault, but get a gas safe registered engineer to check and or replace.
If it is a fan fault, what was the relationship between it failing after the boiler had been switched off and out of action for 10 days?
Power surge, some boilers don’t like being turned off, stupid I know, but i’s the truth. Could be fan pcb.
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Best thing to do is get Worcester out under their fixed price repair scheme
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I will be calling an engineer but would like to know what's going on if anyone can advise: C1 is a fan error code but in the video below there is an odd ticking sound that occurs for a few seconds after switching on the boiler and/or activating heating. It doesn't make that sound again (as you might expect if it's repeating an attempt to get the fan started) unless switching on heat again from off. The sound does not seem to have anything to do with fan itself as I disconnected it and the same issue/sound still occurred. The pump is running fine and is what can be heard in the video.

The ticking sound is the diverter valve motor, it is supposed to do that when you switch the power on and off
The ticking sound is the diverter valve motor, it is supposed to do that when you switch the power on and off
It didn't make that sound when switching on/off before the fault started....
I have a diverter valve on a conventional boiler? I'll look it up in the installer diagram. Definitely not a combi.
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