Glow Worm 18Si

by **shearo** » Tue May 20, 2008 5:54 pm

Could anyone shed any light as to why my boiler has started to lose pressure? I have to re-pressurise almost everyday.I've bled the rads several times.......
Thanks

by **plumbbob** » Tue May 20, 2008 8:01 pm

You have a leak somewhere on the heating system. You will have to examine all the pipework to find the escape.

by **shearo** » Thu May 22, 2008 6:52 am

Thanks for that Plumbob...I've had a look and as yet cannot find a leak could it be something inside the boiler itself like a saftey valve blowing off???????

by **plumbbob** » Thu May 22, 2008 4:24 pm

There is a small copper pipe that will go through the wall to outside somewhere near the boiler see if that is dripping. It is not impossible for the boiler to be leaking internally, but there are more likely places for leaks to occur.

Remember you have a sealed system, and only a very small leak will cause the pressure to drop. Probably a mug full is sufficient so if the leak is slow, most of the water will evaporate and leave little trace.

Check radiator valves and the carpet or flooring where water might drip. Then examine closely any exposed pipework and joints.

You cold try a leak sealer, but I would exhaust every other route first.

by **shearo** » Tue Jun 03, 2008 6:50 am

Hey Plumbob...my boiler is leaking outside! I finally witnessed this , this morning. So what has gome wrong any ideas??? Many Thanks

by **htg engineer** » Tue Jun 03, 2008 3:51 pm

Heating on ? pressure rising - expansion vessel needs re-pressurising or replacing.

Heating off ? pressure rising - hole in plate heat-exchanger - or mains and heating water mixing.

htg

by **adamjoner** » Tue Jun 03, 2008 9:10 pm

hi shearo,
if u have noticed the boiler leaking to outside, then the pressure relief valve is passing and needs replacing, it could also be the charge of the pressure vessel which will allow the pressure to rise above recommended pressure 3bar when the boiler is in use, hope this helps

by **shearo** » Wed Jun 04, 2008 2:38 pm

Thanks adam I've just re-pressurised the system to 2 bar and without anything turning on I noticed the water coming out of the outside pipe.also the pressure has gone down...not surprisingly I suppose?????

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