Gas Work Question

Worcester condensing boiler high pressure

My boiler pressure is too high, it is in the red zone on three and has been like this for around a month since returning from holiday. While I was away the weather was quite cold so thought maybe because I had thermostat turned right down this was why, but pressure seems to have been at 3 almost constantly. When I turn on taps or the washing machine is on, the pipes make a loud banging sound.
There is a tap to top up pressure that the fitter showed me but nothing I can see to release pressure. Any advice appreciated!

2 Answers

Best Answer


If you want to release pressure, bleed an easy accessible radiator. I had to do this on my own. If the pressure keeps increasing, see if the filling loos have been completely turned off.

Hope this helps regards John
Solid building services

Answered 2nd May 2013

Solid building services

Member since 22 Jan 2013

Try and find a drain cock on the heating pipework, attach a hose and run the hose outside, turn the drain cock very slowly until you hear water escaping, keep an eye on the pressure gauge until it reaches 1 bar. Turn off the drain cock and remove hose.

If however the pressure gauge continues to rise after then your boiler expansion vessel has ruptured, time then to phone your local Gas Safe installer to quote for repair.

One point of safety, make sure your boiler is turned off and cold before undertaking this simple drain-off exercise.

Link to a photo of a drain cock to help with location if you do not know what one looks like:

Just copy & paste URL into your web browser.

Answered 2nd May 2013

Boiler Homecare

Member since 6 Jan 2010

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