Do I have to change TRV's when pressurising old GCH system

[interesting100]

Hi - I have what was originally a 20 year old GCH system to be upgraded
We have put a new Greenstar 24Ri boiler in and are going to add an expansion vessel to get HW up to new rads on the 2nd floor

Do i have to change the old TRV's on the existing rads as a matter of course, or is it worth test-pressurising the system to see if they leak or not ?

The TRV's have had new heads fitted - (Wickes ones happened to fit), but the valve bodies and balancers are still the originals -they may be MA brand - logo looks like an upside down W

thanks

 

[glenno1]

How does the expansion vessel get hw to the rads on second floor? Am confused

 

[plumber0808]

I think he means is converting open system to pressurised system.

Its a gut instinct, if the radiator trvs and lock shield valves are 20 years old I would say that is a good innings and have both replaced on all rads. If not its a risk you can take and find out when pressurising.
if they look like there hanging off with crusty bits on them they will certainly leak.

 

[interesting100]

Yes - its probably a false economy not to replace them -