glow worm boiler 18si

Postby texmarshall » Wed Apr 08, 2009 11:20 am

My boiler has recently began to increse in pressure up to 4 bar. My central heating works fine for about 30 mins and then gradually increases in pressure. Water is coming out of the discharge pipe and the pressure is flashing with a red lamp. The only work I have had done on it recently was to have a 2 port valve head replaced about 2 months ago, as it had failed.
Do I need to get somebody out or is there a way I can release some of the system pressure?
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Simply Build It

Postby Steve the gas » Thu Apr 09, 2009 4:10 am


Yes - bleed some water out of any rad - the pressure will reduce, keep an eye on guage as you bleed.

Also is your filling loop valve open a little? This can sometimes be the cause of this. To prove - disconnect filling loop - which you should do by law anyway.

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Postby htg engineer » Fri Apr 10, 2009 10:16 am

Expansion vessel needs re-pressuring or renewing.

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Postby texmarshall » Fri Apr 10, 2009 11:02 am

Thanks for the advice and will be calling an engineer out soon as. Woke up this morning and water leaked all over the kitchen from base of boiler. Time to get on the phone I think.
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