TRV stuck can't get new body

Tim

You might try giving it a good hammering. I once worked at a company with TRVs, I forget the make. In spring as the need for heat finally disappeared, and people would close the valves, eventually to fully closed. Six months later, the building would echo to the sounds of hammering and banging as people tried to get the valves working again.

After a few years in that building, they had the valves replaced with another make entirely. Exactly the same thing happened.

If the ping springs up with no head on the valve, then it seems unlikely the valve body is the problem. If you leave the head off, does it warm up?

Have you tried bleeding the radiator?

If it's a sealed system, is it up to pressure? (Typically about 1 bar when cold, or more specifically, at least half a bar for every floor above the pressure gauge, plus half a bar extra.)

Thanks very much all. In response to the questions. I have tried tapping it with my grips and no joy unfortunately. Yes tried bleeding it no air on there. Also system is pressurised and at correct pressure. There is another identical radiator in the same room which is working fine.

Thanks again

Lee.

What happens when you run the system with the TRV head removed, and the pin raised manually -does the rad get hot then?

If not, are you sure that there isn't an air lock or blockage elsewhere which is preventing any water getting to the rad? Is the lockshield valve at least partially open?

You could try bleeding the radiator with each valve open in turn and the other one closed. You should get a flow of water both times. [If you disturb the lockshield, make a note of how many turns - and fractions - it takes to close it so that you can restore it to the same setting].

Incidentally, if the valve does need a new body, you can get them on Ebay - e.g.

Check that the lockshield valve on the other end of the rad is open (try fully opening it but count the turns so you can put it back where it was)

ditto full of sludge :-(

Dayton do a tool to dismantle the valve body

Oops

Lets try again

David snipped-for-privacy@nospam.com wrote in news:vkmboi$3kun3$ snipped-for-privacy@dont-email.me:

It's possible that tool may be for the next gen of 'self balancing' TRV4s to set the TRV end balancing setting and not necessarily for dismantling. Happy to be corrected.

Still not clear on what has failed in the o/p's case, the body to me is the element screwed into the radiator and containing pin operated valve. If that has failed then it is a drain down replacement for at 25 odd quid for a full replacement of body and head.

It's three tools in one. One of them is to unscrew the seal which holds the valve in the body. At £6 for two they're a bargain and essential for maintaining/repairing Dayton TRVs.

You can also buy the O rings which prevents the valve stems leaking, but Screwfix don't stock them.

Tapping is the way to go.

For some valves, the pin/valve assembly can be replaced. Either drain, or use this to exchange the valve assembly under pressure:

Don't know the name of the tool... the tool is expensive, but is available for rent at tool-hire places here.

Thomas Prufer

David snipped-for-privacy@nospam.com wrote in news:vknccd$3sm77$ snipped-for-privacy@dont-email.me:

Excellent info, thx for sharing/correcting. TRV4s are may fave TRVs.