Identify TRV for me

[coursemyhorse]

I have this TRV in my house but it has never had a top head to it since we moved in. I want to buy one so I can turn the rad off to remove it. The measurements are 15mm pipe work, 28mm main large thread, 19mm across the large hex and 12mm across the internal small hex head bit. I think it is fitted on the return side but I only base this on that side getting hot last. Left side gets hot first when it comes on. There are arrows on the back pointing both down and to the right showing flow can presumably go either way. It also has what I think reads "DN15" on the back. Can I just go down Screwfix and buy some kind.of universal 28mm threaded TRV? If so which?

 

[Madrab]

Buy one of these, it's a decorators cap, it'll tighten down onto the top of the valve and shut the valve off.

 

[opps]

As above but sometimes I have used my nicotine gum to glue a pound coin in the top of the plastic cap to ensure that the pin was fully engaged. Sometimes the cap hits the outlet before fully screwing down.

I also use my gum to hold screws on to the end of long screw drivers when screwing in to deep holes. It sounds grim but it works for me....

 

[JohnD]

What do all the other TRVs in your house look like?

Probably one of the other heads will fit it. And will be identifable.

 

[CBW]

Looks like the stamp is CB which could be CenterBrand (Wolseley). M28 sounds like what you need, lots are compatible, but not all.

 

[coursemyhorse]

Buy one of these, it's a decorators cap, it'll tighten down onto the top of the valve and shut the valve off.

View attachment 282867

Thanks but all the decorator caps appear to be 30mm threads. I guess 28mm must be unusual and possibly older now, even though this rad would have only been installed around mid naughties.

What do all the other TRVs in your house look like?

Probably one of the other heads will fit it. And will be identifable.

They are completely different Danfoss ones without a threaded collar. Instead they have 4 point clip on style bottoms to the heads.

Looks like the stamp is CB which could be CenterBrand (Wolseley). M28 sounds like what you need, lots are compatible, but not all.

That stamp says GB but thanks.

 

[mcprinter]

DIYer
I think it might be a Myson.

You can get 28 to 30mm adapters so you could fit a 30mm TRV head.
Better to fit a decorating cap for rad removal to ensure it is off.

 

[coursemyhorse]

DIYer
I think it might be a Myson.

You can get 28 to 30mm adapters so you could fit a 30mm TRV head.
Better to fit a decorating cap for rad removal to ensure it is off.

Thanks, I ordered one of the myson adapters and a 30mm Myson head to see if this works. I don't know if normal decorators caps will fit but I can try and get one and see too.

 

[Ron In Thanet]

Had similar old trv valves and needed some heads myself.
This looks like your valve (may be wrong thou) https://www.ebay.co.uk/itm/264635764735

This company had compatible heads https://www.heatingcontrolsonline.c...siemens&description=true&category_id=0&page=3

The decorators cap, never heard of them Untill now

 

[coursemyhorse]

So the myson adapter doesn't fit. If I were to push it down super hard and thread it on, it would be permanently shut fully off after only a couple of threads. If I put the head on after that it can't work as the pin wouldn't budge.

Had similar old trv valves and needed some heads myself.
This looks like your valve (may be wrong thou) https://www.ebay.co.uk/itm/264635764735

This company had compatible heads https://www.heatingcontrolsonline.c...siemens&description=true&category_id=0&page=3

The decorators cap, never heard of them Untill now

Thanks yeah that does look like the one. I wonder why they are such oldies for a rad installed around 2005 I assume. I will try that one next

 

[CBW]

You could always change the valve?

 

[coursemyhorse]

You could always change the valve?

I think that involves draining the system and this is a downstairs radiator.

 

[CBW]

I think that involves draining the system and this is a downstairs radiator.

Sometimes it does, depends on the system.

 

[JohnD]

I think that involves draining the system and this is a downstairs radiator.

Does your boiler have a pressure gauge?

 

[coursemyhorse]

Does your boiler have a pressure gauge?

Yes. I also have a pressure guage in the airing cupboard with a fill loop. It's not a combi and I have no header tank.