Evening all. This has probably been discussed to death but I can’t seem to cure this problem. The water comes in the flow side the TRV red hot. The problem is that it doesn’t
fully heat the whole rad. Have tried bleeding it and got some air out but still joy. The water at the other end of the rad at the valve is still cold. Should I try to completely drain the rad out or just bleed again. The rad is a double 1200x600 stelrad on a pressurised system. All the rest of the rads
work no problem. Thanks for any advice
Cold rad on bottom but hot on top
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Bob225
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Re: Cold rad on bottom but hot on top
stuck valve - open the valve fully and give it a tap, it could be sludged up, Take the rad off and flush it with a hose, when was the system last treated and/or flushed, do you have a magna-clean ?
Are both valves on the bottom of the rad ?
I'm just a diyer
Are both valves on the bottom of the rad ?
I'm just a diyer
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wine~o
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Re: Cold rad on bottom but hot on top
Sounds like a sludged up Rad, remove flush through, replace. As an aside are your TRV's Bi-directional ? (Is there an arrow on the TRV body ?)
Verwood Handyman
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Someone-Else
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Re: Cold rad on bottom but hot on top
As said, your rad is full of sludge, it has to go somewhere, and you have now found it. Clean rad (Outside, not in the house) put it back refill add inhibitor.
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Someone-Else
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Re: Cold rad on bottom but hot on top
Turn it upside down and bang it with a rubber hammer as well. (You will be surprised what comes out)
Above are my opinions Below is my signature.
Would you hit a nail with a shoe because you don't have a hammer? of course not, then why work on anything electrical without a means of testing Click Here to buy a "tester" just because it works, does NOT mean it is safe.
If gloom had a voice, it would be me.
Click Here for a video how to add/change pictures
Inept people use the QUOTE BUTTON instead of the QUICK REPLY section
Would you hit a nail with a shoe because you don't have a hammer? of course not, then why work on anything electrical without a means of testing Click Here to buy a "tester" just because it works, does NOT mean it is safe.
If gloom had a voice, it would be me. Click Here for a video how to add/change picturesInept people use the QUOTE BUTTON instead of the QUICK REPLY section
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arco_iris
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Re: Cold rad on bottom but hot on top
How old / what make / can we see picture of the TRV? Old style Drayton TRVs have a habit of the pin sticking, and may have been fitted on the flow side, not necessarily with a bi-directional arrow on the valve body.
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If the trv head appears to be held on with a clip, like a jubilee clip but with a screw & nut, undo it, wiggle the head off the valve, grip the exposed pin with pliers, work it in and out a couple of times to free it. It only moves a small amount.
Other makes suffer similarly - undo the knurled ring that holds the head to the valve, do the same. I had this issue regularly at a previous property & it was nothing to do with sludge.
)))
(((
If the trv head appears to be held on with a clip, like a jubilee clip but with a screw & nut, undo it, wiggle the head off the valve, grip the exposed pin with pliers, work it in and out a couple of times to free it. It only moves a small amount.
Other makes suffer similarly - undo the knurled ring that holds the head to the valve, do the same. I had this issue regularly at a previous property & it was nothing to do with sludge.
)))