vaillant boiler cuts off

21 Oct 2010
Reaction score
United Kingdom
Hello everyone,

Posted yesterday but now my vaillant boiler model vc gb 110 h.

Now I can light the pilot but the boiler fires for 30 secs to 3 min then cuts out and switches off the pilot light. Can relight but happens again.

Had the expansion vessel and thermocouple replaced.

Any suggestions?

Thanx, Tony
Sponsored Links
haven't got the manual so not sure what components your boiler uses - is the pilot permanent when lit or does it come on intermittently eg/ when there's a demand from heating or hot water??

have you checked the pump?

Thanx for replying,

Pilot light is permenant. Pump is working as even when pilot light is out can hear it working.

Any suggestions?
what does the pressure gauge show? is there air in the system? is the system water dirty??

could be a few things but would be gas related
Sponsored Links
Pressure fine just above 1.

no idea on the rest. Do have a man who should be comming back to have a look (he replaced expansion vessel) but he said he didnt know what was wrong.

Any suggestions i could pass on?

you say the pump is working but hae you checked it fully?

could be a thermostat/thermistor fault

need to check eveything

I haven;t got the manual at the mo so can't see what components your boiler has
To be honest wouldnt know how, just sounds like its working.

Will pass this on to my guy along with other suggestions, Thanx.
This is now a gas fault mate it could b overheat stat/ interrupter fault or probably vitiating due to blocked fins on ht exch dont use until reg installer who knows what there doin looks at it it could b spilling co!!!!
Ok thanx,

Probably gonna need to get someone else in my guy is not returning my calls, so unreliable.

Thanx again

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Sponsored Links