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Discuss Radiator not heating up and loss of pressure in boiler in the Central Heating Forum area at PlumbersForums.net

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One of our radiators is not heating up, it just gets a little warm. We've also noticed loss of pressure in the boiler, we have to keep manually increasing the pressure.

Could both issues be related? We don't see any sign of water leak around the problem radiator.

Any advice will be appreciated.



Gas Engineer
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It could be the cause of the pressure loss if there’s a leak under the floor that feeds it. Check the copper pipe that exits outside, see if that drips. Radiator might just need bleeding for the loss of heat.
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Thanks for your reply.

There's no copper pipe. It has plastic pipes which run into the wall, not the floor. I've attached two photos of the pipes.

I tried to bleed the radiator but water immediately poured out. Does that mean there is no air trapped in it?


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We have basket under the boiler, which is never wet so I don't think any pipe is dripping. I've attached a photo of the pipes under the boiler, which one is the safety discharge pipe?

Any idea about the radiator? It doesn't have air in it and it doesn't visibly leak. It does for some reason gets slightly warm at the top but remains cold at the bottom.


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Its the one on right hand side check it outside to see if its dripping
Have you tried running heating with all radiators turned off except the one giving trouble? Also probable first take thermostatic head of valve on right hand side check pin under head moves easily tap gently to move.
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Pressure release valve could just be a faulty valve but there are other reasons it could have operated as I said needs competent gas safe registered engineer.

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