central heating problems

[dannib]

Hi.

I have a vaillant combination boiler, there is no model on it that I can see.

We are having problems in that the boiler is coming on, and hot water & heating work ok, but then central heating will just go off.

If we turn it off, turn pilot light out and then light it up again and turn it on it usually works again, but then after a while will just go out again.

We have bled the radiators, they all work fine when its working and I dont know what to do!!!!

I have 9 month old baby, a freezing cold house and its snowing!!! help!!!!

Thanks

Danni

 

[kevplumb]

if you bled the rads did you top the pressure back up to 1 bar

 

[dannib]

yep, pressure is back up, but still no heating!!!

Any ideas??

 

[kevplumb]

need the model there are at least 2 vaillant combis with pilots and they are totally different

describe the boiler

 

[dannib]

I've found some numbers not sure if is model or not though.

Its got: VCW GB221H

Is this it??

 

[kevplumb]

thats it

check the auto air vent on the pump (bottle thing ) with a black cap on it should be loose

is the pump running

is the heating going off after you run the hot water

 

[dannib]

Can't see a black cap on the pump (or a bottle type thing).

The pump runs, no problems. and the boiler makes noises, but just doesnt ignite.

No the heating doesnt go off after I run hot water.

Sorry i'm not very technical!

Thanks

 

[kevplumb]

my appologies its at the top of the case on the right make sure the cap is loose

 

[dannib]

found it, and yes it is loose.

 

[DP]

>>>>>No the heating doesnt go off after I run hot water. <<<< What do you mean? The heating cannot be on when you ask for hot water. This boiler (like all combis) will only give you hot water or central heatin- never both.

 

[kevplumb]

was thinking servo valve sticking dp

might be the high limit stat but i cant remember where it is on the boiler

 

[dannib]

sorry, thought you meant does turning hot water on make it go off completely and not come back on again!

sorry

 

[dannib]

thanks for your help anyway.

You've been very kind to help so far!!

Looks like i'm gonna have to call someone out.

Thanks again

Danni

 

[kevplumb]

just read your first post again whats going off the boiler or the pilot light

 

[dannib]

the pilot light stays on, and the boiler goes off.

If I turn pilot light off and then put back on again it will then work again though.

I just tried what you said about does it go off after hot water being on, and the heating has now gone off and radiators are now going cold.

Could this be something do with it??