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Slight leak from combi boiler?

Hi, I have a small leak from what I think is the pressure relief valve on my combi boiler in our new house- I can supply a photo.
On the day we got the keys the pressure was a little below one bar so feeling clever I opened the valve to increase the system pressure - unfortunately it went up a bit too quickly, the pressure is now on the recommended line (about 1 bar from memory) but there is a small leak (less than a cup per day).
Hoping someone can help.

3 Answers from MyBuilder Plumbers

Best Answer

You have two options: a short turn of the head on the pressure reducing valve will release a small burst of water, possibly clearing a small piece of debris, which will not allow the valve to fully close. Option 2 would be to replace the pressure reducing valve if option 1 does not work, this would require a professional. I reccommend that your pressure is set between 1.2 and 1.5 bar when the system is fully cold and that you remove your filling loop once done.


Answered 18th Jun 2011

Sounds like you may need to replace the pressure relief valve, you could try flushing it through with clean water


Answered 10th Jun 2011

Disconnect the filling loop (the braded pipe that puts the water into the boiler).
Check to see if the water is coming from the boiler end of pipe or the mains.
If boiler then the preasur valve seat has not sat down properly and just needs a burst of water (not tooo much) to re align it.
If coming from the mains side just turn the valve of fully.
any thing else just ask.
Please not that the filling hose must be disconected after filling(Local water by law requiers this).
regards Ashley


Answered 11th Jun 2011

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