One radiator not getting hot

17 Jan 2013
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West Midlands
United Kingdom
Hi there,

I know absolutely nothing about plumbing/radiators/etc. However, there is one radiator in our house that does not work. I tried bleeding it at the top and nothing happened. The thermostat is on high and the pipes from the wall are boiling but the radiator itself does not seem to get hot.

I also opened up the valve on the opposite side from the thermostat on the bottom left and water starting gushing out. I let about half a jug full out. Once I did this, the whole radiator got hot and I thought I'd fixed it but when I came back to it later, cold again.

Does anyone know what the problem is?


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Weird looking setup.

Is that a drain-off valve shoved in where the return pipe should go???
If both pipes coming out of the wall are hot then the valve on the right has failed - it's supposed to have an injector inside it to force water into the radiator but these corrode and fall off, leading to a short circuit through the valve. To the best of my knowledge you can't buy these valves any more - the radiator will need re-piping so that one pipe goes to the left hand side, and new valves putting on
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