Rad valve connection size is different from valve

6 Oct 2008
Reaction score
United Kingdom
The drayton TRV 4valve I have purchased has a 15mm connnector to the rad. The rad however has an existing connector which is 3/4 If I try and remove this existing connector I am afraid that it may break. Is there a way to keep the existing rad connecotr in place and connect to a Drayton valve? Thanks
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Thanks...I don't want to risk replacing the tail so guess it is the valve option. Do you know of Drayton have such a valve?
don't know any trv's that are 3/4 fitting.

why do you think it will break. if you use the allen key to remove it it will either undo or not you shouldn't damage it either way.
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The connection appears to be corroded internally so not sure the allen key will connect and so nervous about trying to remove it, thought it might be easier to leave in place and find another option...but also wanted to install a TRV rather than a plane valve.
whats the other end like ?
you could use a bi directional valve and put it on the outlet of the rad if that better.
Good idea did not look at the other end...the valve is a drayton trv4 which says it is bidirectional

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