Replacement TRV/heads for 10mm piping
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Replacement TRV/heads for 10mm piping

by MickySparker » Sat Apr 09, 2022 12:12 pm

We've a utility room radiator with 10mm pipework; fitted about 6 years ago it has a BOSS TRV which has failed (the sensor plunger just flops around - as if the wax sensor has leaked) and the radiator is always "on".
I don't consider 6 years a reasonable life so I'm reluctant to buy another BOSS head (or whole valve) only to have to replace it in another 6 years.
Alternative 10mm valves seem thin on the ground so I was tempted to change to a 15mm valve with a suitable pipe adaptor and use a known "good" brand TRV, but because the 10mm pipes come out of a stud wall about 35mm below the valves (via a 90 degree elbow) and within the wall the 10mm copper couples to plastic pipe - unsoldering the 10mm elbow & resoldering a 15mm one may well damage the concealed plastic/copper coupling.
Using a big-name valve with a 10/15mm fitting is out of the question because the short stub of 10mm pipe above the elbow would need the olive removing and cutting the pipe off below the olive wouldn't leave enough pipe for the adaptor & a new olive.
An unwelcome solution would be to cut a hole in the plasterboard to access the copper/plastic coupling before unsoldering and then make good the wall (wife extremely unhappy with this idea!).
A far easier/cheaper option (but no so practical for comfort) would be to leave as is and simply use the lockshield to limit the flow.
My questions are....
1. Are BOSS reliable and have I just been very unlucky? (and I can simply replace the head with another BOSS one!)
2. Does anyone know of a reliable brand whose sensor-head would be directly interchangeable?

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Re: Replacement TRV/heads for 10mm piping

by stoneyboy » Mon Apr 11, 2022 11:02 pm

Hi mickysparker,
Save yourself a lot of hassle and replace like for like.
Regards S

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