Drayton TRV if turned to * - just past frost is that shut off?

[WaterTight]

And failing that how cold does it need to be before frost stat would open valve slightly...?

Can you fit a cap to keep the valve closed after removing the rad or will taking the TRV head off open the valve?

 

[PlumbBobBob]

yes the trv should be shut off when at * past frost. failing that you can keep the valve shut with a cap screwed in place of the trv head they usually come as part of the trv kit

steve

 

[kirkgas]

And failing that how cold does it need to be before frost stat would open valve slightly...?

Can you fit a cap to keep the valve closed after removing the rad or will taking the TRV head off open the valve?

you need to fit the decorators cap BEFORE you remove the rad, as you say when you remove the TRV head you will get full flow, even with a cap on it i always fit a blank end to the valve body "just in case" been there done that with a TRV dripping it either causes damage or switches off sealed systems, its like all these other bits & bobs we have and keep using, make up a blank end on a small stub of pipe with a nut & olive on the other end, (most TRV's are now 15mm, older ones require the stub to be taken out of the rad and something made up to blank off the 1/2" BSP thread

 

[PlumbBobBob]

i keep a small supply of 1/2 and 3/4 caps just for such occurrences usually with a rubber washer inside

steve