Pressure rises on my central heating system.

[Terry Jones]

Hi all,

Wonder if you could help me with an on going problem I've got. I've recently had two Gas Safe engineers out and neither have been able to assist.

I have a Worcester Greenstar 28i junior that when run on heating after a while the pressure climbs to 3 bar and starts to dump it's water. I had the boiler serviced and when the engineer carried this out he recharged the expansion vessel but the problem remained, he came back but was at a loss. I had a subsequent guy out who could not fully diagnose the problem other than say it was likely a blockage in the boiler somewhere close to the expansion vessel but he couldn't guarantee this. He said it'd be quite a bit of work to remedy if this was the case. As he was a little doubtful I thought I'd ask your advice before taking the plunge. Is there any other possibility that it could be anything else?

Yours in advance,

Terry

 

[Terry Jones]

Sorry, one other thing I forgot to mention was that my boiler had sprung a leak prior to me having it serviced and a manifold (according to my paperwork) was replaced. I'm not sure where in the boiler this is but it seemed to be from the lower left hand side as you looked at it. I can't say if this ties in with the issue with the pressure but I don't recall seeing water coming from the discharge pipe outside prior to having that replaced.

 

[jamesgmg]

Same problem here on an 18 month old worcester 32cdi compact. Just has secondary heat exchanger replaced and pressure vessel recharged (was actually too high). Suspected pin hole on heat exchanger allowing mains water into central heating.

It's only just been done so I'm monitoring the pressure at the moment, so not sure if it's resolved yet.

 

[hazetimesfive]

If you turn the cold water inlet off then you will know without guessing.

 

[Terry Jones]

Ah, I see when it's cold that the pressure is at 2.5, where a day or so ago it was set at 1, that makes sense!!!! Thanks for the advice.

 

[hazetimesfive]

I dont know what you just said.

 

[Terry Jones]

Sorry I meant that it sounds like my DHW HE has got a leak in it as the pressure has risen.