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Why so much water draining from upstairs radiator?

Postby kgb » Thu May 14, 2009 4:17 pm

Hello,I am in the middle of re-doing our bathroom. I want to change the radiator.

Trouble is I can not stop the water coming out of the radiator. Plumbing is not my strong point. This is what i have done

1 Turned off heating system
2 isolated water supply
3 Tried to drain old radiator

This is an upstairs radiator and i am not sure where it is fed from, it is the only upstairs radiator in the house.

If radiators are based on a feed and return system then why is water coming back up both feed and return pipes. It surely can not be draining the whole system if it is upstairs can it?

At the moment i have put a push fit connection on the supposed return pipe and draining it off into the sink waste pipe. this was done two hours ago and water is still coming out.

the pressure in the heating system can not be enough to push the water upstairs can it?

Can anyone help this rather soaked individual
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Postby rosebery » Thu May 14, 2009 10:14 pm

If you have a combi then unless you reduce the overall pressure in the system this is bound to happen until you have.

If you have a more conventional system with an F&E tank in the roof the feed will keep feeding until it is drained and if you haven't isolated it it will keep feeding until you feel ready to draw pension.

Yes the pressure in flow and return has to be the same and if you open both then it is bound to come out of both.

No you are not draining the "Whole" system but the water has to find a level and if that is still above the valves for the radiator then ..........

Do you think a plumber might be in order for this job?

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Postby htg engineer » Fri May 15, 2009 2:48 pm

What type of system do you have, the best bet is to drain from a downstairs radiator then you will drain upsatirs and all the pipeework above the down stairs radiators.

If it's still running after 2 hours then check you have isolated the water supply, your mains stop tap may be passing.

I don't think you will have a combi/pressurised system, as if the fill loop is turned off then it shouldn't run for 2 hours and the pressure would be lost after 2 minutes.

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Postby kgb » Fri May 15, 2009 5:02 pm

"Do you think a plumber might be in order for this job?" Lol, yes I do, but the bank balance says no.

I sorted it,

The header tank was knocked off via a bit of pipe under the float so no water was coming through there. what was confusing me was that when draining the hot water storage tank with the downstairs taps it emptied out, so i presumed that it was empty. Obviously the pipes feeding this radiator were much futher down the tank than the pipes feeding the downstairs taps. I think that is what was happening.

Thanks for the replies

BTW Im an ex bricklayer so it's no wonder i don't know what I'm doing :)
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