Replacing thermostatic valve on a Drayton TRV2

[Quick learner]

Is it necessary to drain the radiator before replacing with a new valve?

 

[Agile]

I have never heard of a Drayton TRV2 ! Are you sure thats is correct?

To replace any TRV you need to mostly drain the part of the system where the rad is fitted.

Tony

 

[Quick learner]

I have never heard of a Drayton TRV2 ! Are you sure thats is correct?

To replace any TRV you need to mostly drain the part of the system where the rad is fitted.

Tony

I have the original Instructions for the Drayton TRV2, but they don't stipulate how to replace the valve. I could have sworn my old (retired) plumber didn't do any draining!

Thanks anyway.