Old vaillant boiler - ignites but keeps clicking to try to ignite

[azc]

Hi all,

In my office (which is subject to a full and repairing lease unfortunately), I have a Vaillant Thermocompact VC 142. It has always been a bit dicky when it is first started with the winter season, but on this occasion, it won't play ball at all.

My local heating engineer tells me that it has been obsolete in 2019, so it is hard for him to get support on it. So I'm trying to research and find the problem, then get him to change parts (I don't want to pay for his time to do the research!).

The problem is that the boiler ignites, and you see a flame, but it keeps clicking like it's trying to ignite. It then locks out. If you reset the lockout, it just does the same again.

The air pressure switch is working, and the fan control module is working. I've been told that the electrodes are OK as well and don't look dirty.

Can anyone offer any assistance please? I was told that the next step was the flame control module, but that's not a cheap bit.

I suppose that it's cheaper than having to buy a brand new boiler for the landlord to benefit from though!

Thanks in advance!

 

[wannocks]

This is a gas related question, and tricky to diagnose correctly from afar, so you're better off sticking with the engineer's advice.
This is an old boiler (very good in its time) and has some obsolete parts, so you can't guarantee anything.
Fixed price repair from vaillant is no longer available for these.

 

[Harry Bloomfield]

The problem is that the boiler ignites, and you see a flame, but it keeps clicking like it's trying to ignite. It then locks out. If you reset the lockout, it just does the same again.

The air pressure switch is working, and the fan control module is working. I've been told that the electrodes are OK as well and don't look dirty.

Can anyone offer any assistance please? I was told that the next step was the flame control module, but that's not a cheap bit.

I would guess at the flame sensor, or flame control module. Begin with the cheaper part, the flame sensor.

There is a manual here - https://www.acwilgar.co.uk/Boiler-Manual-PDF/Vaillant/Thermocompct VC GB112EH 142EH 112EB 142EB.pdf

 

[azc]

I would guess at the flame sensor, or flame control module. Begin with the cheaper part, the flame sensor.

There is a manual here - https://www.acwilgar.co.uk/Boiler-Manual-PDF/Vaillant/Thermocompct VC GB112EH 142EH 112EB 142EB.pdf

Thank you. I've ordered a new flame control module (only £35 off ebay), so we will see how we get on. I will look for the sensor as well.