TRV with 1/2 in BSP inlet

[Newman]

I need to replace a leaking TRV. Where can I purchase a reasonably priced angled TRV with a 1/2 inch BSP female inlet?

Regards

[John Rumm]

The BSP female input seems to be a thing from way back, I have not seen any new ones like that.

A TRV with a push fit base and slightly longer stem might make for an easy swap, if you can cut the pipe stem to the right length (and assuming its 15mm):

[Newman]

Thanks

It is 15mm. Does a 1/2in BSP fitting have an olive in the pipe?

[John Rumm]

No, a BSP fitting on an old rad valve was usually just a female threaded socket. You needed a male threaded connector to connect to it[1]. They would typically have a flat machined surface where a seal could be made with a fibre washer. Alternatively, one would use a tapered male fitting, and PTFE / Hemp or some other thread sealant to make a seal on the threads.

Modern rad valves usually have a 15mm compression fitting with its own back nut which does use an olive.

[1] Often a male BSP to 15mm compression adaptor would be used to in effect turn the TRV into a compression fitting. About the only time the BSP TRV would be useful directly would be on a system piped in "iron barrel" pipes with threaded connections. There it could screw directly onto a threaded pipe tail.

[Newman]

Thanks again.

So, if I remove the male BSP fitting from the pipe, that will leave a bare 15mm pipe to which I can then fit a normal 15mm right angled TRV?

[John Rumm]

Yup that sounds likely - post a photo somewhere we can see if it you want me to check...

However this was a photo someone posted a few weeks back:

It shows a rad valve with a female BSP socket that points down, and then a male BSP to compression adaptor screwed into it so that it can connect to the pipe. If yours is something like that, then yup. Chop off the pipe under the compression adaptor, and extend if necessary, then connect to new valve.

[Newman]

Thanks

It will be a couple of weeks before I am going to tackle this. I am just gathering info so that I have the correct fittings available to cover all bases.