Radiator not heating up

10 Apr 2005
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United Kingdom

I have recently clear out our spare room and turned on the radiator . The radiator is about 2 and half years old , never teally used as is the trv and lockshield.

I have noticed that the rad is not getting very warm. I have put the trv on 5 and still its only getting lukewarm. I checked that the lockshield was open and it was and i’ve also opened it fully and still no joy. I have bled the radiator and still no real inprovement . I have taken off the the trv checked that the pin is miving up and down and it is . The pipe to the trv is warmish but coldish to the lockshield. The rad just wont get hot. All other rads in thehouse are fine

Can anyone help?

Also as a note i am a bit confused about the Lockshield that i have .. see photos i have attached as i am not sure this is a lockshield or just a manual trv. Its a wheel type. I read up that older rads may have these but this is not that old at all. I can’t seem to unscrew the wheel to take if the head.
Any help appreciated


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It's a lockshield on the left, and a TRV on the right - there isn't a manual TRV though. As Gordon has suggested, turn of the TRVs on the other rads, and see if the blockage clears. If the rad gets hot, then you know it's okay, so then set the lockshield to about 1 turn open, and then turn all the other lockshields down by about an 8th of a turn, and see if that shifts the balance of the heat into this rad. You may also need to turn down from 1 turn, or even slightly up.

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