Do they exist? I have a rad off to decorate, and the thermo valve has just
opened & dumped the system contents into the room/garage.
Can I get a screw on cap anywhere to blank off hte open end of the valve, or
is there another way to stop it opening?
In article ,
The ones which don't have an off position normally come
with a decorator's cap. You take off the TRV head and screw
down the decorators cap instead, and this seals the valve
I did find a Pepsi screw bottle top fitted the outlet on
some valves, but there's more than one size.
In an earlier contribution to this discussion,
As others have said, the TRV should have been supplied with a 'decorators
cap' which screws on, once you've removed the thermostatic head, and holds
the pin firmly down. If you don't use that there is a danger - as you appear
to have discovered - that if the temperature drops sufficiently the valve
will open, even on its lowest setting, and cause a flood.
If all else fails, find something (e.g. one or two 5p pieces) which you can
sandwich between the valve and the head, to make sure that the pin stays
down under all circumstances.
Alternatively . . .
Do your radiator tails have the equivalent of a compression joint where they
connect to the valves? If so, you could make up blanking-off devices with
the following ingredients for each one: Short length of 15mm copper pipe,
15mm olive, compression nut, 15mm stop end.
Your rad valve outlet would most likely be either three quarter inch or half
You can pick up brass or iron caps from the plumbers merchant.
If you use brass then fit these with a rubber or fibre washer.
If you use iron caps then it is best to wind ptfe tape on the threads.