Combi Boiler and turning off water supply

OhGranny

Hi
I have been doing some work on my bathroom and have had to turn the water supply off a few times.
Now when I turn on the cold tap the boiler pump (or something inside) operates for a few seconds the pressure drops to .8 then goes back up to 1 bar. The boiler doesn't ignite but something runs inside. It never used to do this before!
I have always turned the boiler off when the water supply was off in case someone turned the hot water tap on accidently but I have never turned off the water supply to the boiler.
The boiler still give hot water but I am a bit worried now that something is running inside when I turn on the cold water tap. Something has changed.
I have a manual but can't see any advice or procedure to follow if disconnecting the water supply.
Any ideas or advice please?
G.

sooey · Posted: Sun Sep 20, 2009 7:54 am Post Subject:

Have you fitted mixer taps, or created a dead leg somewhere in the pipe work.

kevplumb · Posted: Sun Sep 20, 2009 8:12 am Post Subject:

run all the taps one at a time you have air in the pipework

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sooey · Posted: Sun Sep 20, 2009 8:30 am Post Subject:

It's obviously a combi, so any air can only be trapped in a dead leg.

kevplumb · Posted: Sun Sep 20, 2009 8:33 am Post Subject:

sooey wrote:

It's obviously a combi, so any air can only be trapped in a dead leg.

yup what would you call say a basin feed full of air

or a shower that hasn't been ran

might be obvious to me and you but we ain't there

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sooey · Posted: Sun Sep 20, 2009 8:35 am Post Subject:

Come on kev, you've got to assume that he's ran all his taps plenty, after doing new work and before posting on here.

sooey · Posted: Sun Sep 20, 2009 8:36 am Post Subject:

and stop editing your posts you b*****r.

kevplumb · Posted: Sun Sep 20, 2009 8:38 am Post Subject:

never assume anything on here

like my boiler wont work on heating

have you turned the selector to water / heating

oh thanks it worked

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sooey · Posted: Sun Sep 20, 2009 8:40 am Post Subject:

OhGranny · Posted: Sun Sep 20, 2009 8:47 am Post Subject:

Thanks lads that's put me at ease a bit at least the boilers not K********d.
I've got the bath out at the moment to plaster so the taps hadn't been run the bath pipes had air in.
I undid the taps and a large gush of air came out the combi seems O.K.
In future should I turn off the water supply to the combi boiler when I turn off the water?
G.

sooey · Posted: Sun Sep 20, 2009 8:50 am Post Subject:

Quote:

I've got the bath out at the moment to plaster so the taps hadn't been run the bath pipes had air in.
I undid the taps and a large gush of air came out the combi seems O.K.

Aaaarghh

Quote:

In future should I turn off the water supply to the combi boiler when I turn off the water?

No need if you turn off the water at the stopcock anyway.

kevplumb · Posted: Sun Sep 20, 2009 9:15 am Post Subject:

sooey wrote:

Quote:

I've got the bath out at the moment to plaster so the taps hadn't been run the bath pipes had air in.
I undid the taps and a large gush of air came out the combi seems O.K.

Aaaarghh

Quote:

In future should I turn off the water supply to the combi boiler when I turn off the water?

No need if you turn off the water at the stopcock anyway.

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sooey · Posted: Sun Sep 20, 2009 9:34 am Post Subject:

That's what I like about you kev, you're so subtle and debonair.

dextrous · Posted: Sun Sep 20, 2009 9:37 am Post Subject:

There's nothing like a good winner

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kevplumb · Posted: Sun Sep 20, 2009 9:38 am Post Subject:

sooey wrote:

That's what I like about you kev, you're so subtle and debonair.

yup and we have all been caught out at sometime

missing the freakin obvious

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