Drayton TRV4 valves

[Stevelwg]

I have a mixture of Drayton TRV4 and Honeywell radiator valves on my heating system,and I have now had two TRV4 valves where the central pin that opens the valve,has come out a lot further,causing the valve to stay shut all the time(this seems to happen over the summer period when the heating is off).Anybody got any answers as to why or how to cure it or stop it happening to any more?

The reason the pin comes out is that the valve has been subject to overheating. The valve heads are designed to work over a the normal boiler outlet range of temperature but work best with boiler outlets in the 65 to 75 deg C range (the mid ponit on the outlet temperature control of most domestic boilers. Although the valve head is supposed to be able to cope with temperatures slightly in execess of 100 deg, in practice if they see a high temperature the gel can over expand forcing the pin down and effectively breaking the unit. Check to see if the boiler outlet temperature is set properly and /or if the temperature controller is working. If the valve head pin is stuck down only a few mm then try putting the valve head in the freezer - it may cause the gel to shrink and pull the pin back to its proper position- more than a couple of mm however and the valve head has to be replaced.

 

[D_Hailsham]

I have a mixture of Drayton TRV4 ... any more?

The reason ...has to be replaced.

You are a bit late answering this. The last post was in March 2006.

Check the post dates!

 

[BingoBongo]

well done on your first post from 3 years ago

it might take a while to catch up

 

[Nige F]

Well at least the anger management course worked did I really say that Sincere apologies.

 

[Timbo5301]

Don't recommend these are they are poor quality and often poorly manufactured. We (plumbers) are not going to use them anymore.