Draining the central heating system

Postby yrrab » Sun Sep 26, 2010 11:05 am

I have been having problems draining my central heating system. I have two draincocks in the garage underneath my combination boiler. One is 1100mm from the floor, the other is 200mm up. I have no problems with the higher draincock and water flows out as soon as I open it. Nothing drains out of the bottom draincock however, which means that I can't empty the radiators downstairs. I am about to change the radiator in the hall which will involve some adjustments of the pipework. Obviously I won't be able to do this work if I can't empty the lower half of the system.
Has anybody got any ideas why the lower draincock won't work? Is there something obvious that I am not doing?
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Simply Build It

Postby htg engineer » Sun Sep 26, 2010 4:05 pm

The rubber seal may have become dis-lodged, try putting a thin screwdriver in and move it about, have hose ready, and you may have to renew rubber washer on drain valve before refilling.

htg engineer
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Postby yrrab » Sun Sep 26, 2010 7:39 pm

Thanks for that reply. I'll have a look at the rubber washer and see if I can sort it out.
Posts: 19
Joined: Thu Apr 09, 2009 3:52 pm

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