Replacing prv valve

[carlbhoy]

Hi, I want to change my Prv valve in my grant vortex eco wall mounted Combi boiler, as pressure keeps dropping, on undoing the valve would there be any water ready to come out if the pressure was on zero, if so would it be easy to contain ?.
Would I have to turn off any water supply other than the filling loop?

 

[Madrab]

Not knowing the oil bolier I couldn't be sure but you would normally have water in the boiler above the PRV, that could be a substantial amount. Usually you would open the PRV until it's stopped running, if you are going to replace it. That way you are sure the amount of water left would be minimal.

 

[ianmcd]

you would be better checking the expansion vessel , what does the pressure guage read when the CH has been on for an hour ?

 

[Exedon]

When we change PRVs on Grant's we always partially drain boiler.
Make sure you get correct prv for boiler in general the combi's have a 2.5 bar, system boiler 3 bar.
You will need a correct sized spanner on the brazed on socket before taking out prv.