Replacing TRV's (picture added)

[paraboy]

What size should I order, do I measure the width of the copper pipe going into my old TRV's. And what are the valves called on the opposite side of the rad. Sorry but not a plumber.

 

[denso13]

Lockshield valves on the opposite sides. Yes, you can measure - probably 15mm, 10mm or 8mm. Or post a piccy?

 

[muggles]

You might have old ¾" unions on one end, best to post some pictures so we can confirm and advise

 

[paraboy]

Will post a pic tomorrow, thanks.

 

[paraboy]

Hope you can help me with the photo, cheers.