TRV 3 or 4?

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Woodco987

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• 21 Feb 2015

• #1

Hi

I need to replace a Drayton TRV that is not working but I am not sure if it is a TRV 3 or 4. Can anybody tell from the picture or advise how I find out?

Many thanks

Untitled

• Woodco987
• 21 Feb 2015
• 1

 

Dan Robinson

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• 21 Feb 2015

• #2

Looks like a 4

 

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D_Hailsham

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• 21 Feb 2015

• #3

Untitled

• Woodco987
• 21 Feb 2015
• 1

TRV3. There is a single arrow on the body, pointing towards the rad. TRV4's have two arrows.

Is it the valve body or the head which is faulty?

If the head, you can get a TRV4c head, part no 07-94-012.

 

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Woodco987

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• 21 Feb 2015

• #4

Thanks for the quick reply. I think it is just the head as the pin still moves up and down in the body if I press it. Radiator is just on full hot regardless of what number the dial is set to and the temperature of the room. Should changing the head fix this? Thanks.

 

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D_Hailsham

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• 21 Feb 2015

• #5

Do you have a clamp, or something similar to hold the pin down?

If so, this will prove if the valve body is working OK.

The conversion head is available on Ebay for £19.99 with free click-an-collect at your local Argos.

 

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Agile

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• 21 Feb 2015

• #6

Bearing in mind that is the same price as a new TRV4 which are far better, my action if it was mine would be to control the rad from the lockshield ( or the decorator cap on the TRV if you still have it.

Then replace all the TRV3s with TRV4s when you have the time and money.

The TRV3s used to be favourite for sticking off!

Tony

 

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Woodco987

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• 21 Feb 2015

• #7

Holding the pin down seems to turn the rad off so I think it must be the head that is the issue. I think I will try the conversion head first as replacing the whole TRV is probably a beyond my DIY skills! Thanks for all the advice.