Trv valve doesn't look right

[Ramprat]

Hi,

Does anyone recognise this valve?

It had the same thermostatic head on it as the others in our house but the valve looks totally different, the others were Drayton types i think.

This rad is getting very hot no matter the setting, I took it apart thinking the pin was jammed but I don't think that middle bit is a pin, if it is its jammed tight as no give at all when wiggled with pliers.

Any ideas? I'd rather not have to replace the valve now as having some work done after Christmas which will require draining the system so do really want to do it twice but the room the rad is in is our bedroom and its so hot in there by the evening so need to try and fix, atleast temporarily.

Thanks

 

[pejoli]

Hi,

Does anyone recognise this valve?

It had the same thermostatic head on it as the others in our house but the valve looks totally different, the others were Drayton types i think.

This rad is getting very hot no matter the setting, I took it apart thinking the pin was jammed but I don't think that middle bit is a pin, if it is its jammed tight as no give at all when wiggled with pliers.

Any ideas? I'd rather not have to replace the valve now as having some work done after Christmas which will require draining the system so do really want to do it twice but the room the rad is in is our bedroom and its so hot in there by the evening so need to try and fix, atleast temporarily.

Thanks View attachment 46603View attachment 46604

Well that's weird - I was about to post about a similar problem, and I have exactly the same valves - all of mine have bulldog heads on them, so I assume that's the brand.

My symptoms are that I can turn the heads to 0, and the rad goes off (and I can push the 'nub' in and out ok) , but anything from '*' onwards is full-blast. Same problem ? It seems to be the same on every rad in my house.

 

[Timmy D]

Yes that’s the pin. Hit it with the persuader.

 

[Basher]

Or if you've got a lockshield valve on the other end of the radiator, you could turn that down (count the amount, so you can get it back roughly where it should be for balancing after Christmas).

 

[SimonG]

Pegler bulldog valve.

 

[Ramprat]

Well that's weird - I was about to post about a similar problem, and I have exactly the same valves - all of mine have bulldog heads on them, so I assume that's the brand.

My symptoms are that I can turn the heads to 0, and the rad goes off (and I can push the 'nub' in and out ok) , but anything from '*' onwards is full-blast. Same problem ? It seems to be the same on every rad in my house.

Mine doesn't move at all tried small hammer and wd40 but no joy going to try large hammer next ha ha.

Could you post a picture of yours so I can see how high the pin should be, also have a theory based on some info id seem else were that maybe the pin is to short for the head, either due to wear or incorrect head type, that might explain why when you turn yours up past 1 its full on as the pin rises to far? Its only a guess to be honest but seen elsewhere a couple of people have put small magnets ontop to act as an extension and it solved the issue but that was a Hive thermostatic head, don't know if that helps?
[automerge]1607428495[/automerge]

Yes that’s the pin. Hit it with the persuader.

Thanks good to know I'm whacking the right thing and going in the right direction in trying to free the pin, was just concerned that it might not be a trv and that it wasn't a pin before I went yanking it with pliers to try and free it up

 

[steadyon]

pejoli:
1. the TRV senses the temperature of the air in the room, not the temperature of the water in the radiator.
2. As the room air temperature rises to meet the temperature set on the TRV, the valve gradually closes. This restricts the flow through the radiator, and the amount of heat transferred to the room, until it closes.
3. The temperature of the water in the radiator, and hence its surface temperature, will only gradually decline as the valve closes, because the heat is being lost to the room. The temperature at the flow side of the radiator will remain virtually the same as the boiler flow temperature until the valve closes.