Hot Water Tank Expansion Vessel Question

[ShaunCorbs]

Are you g3 registered as your working on an unvented?

 

[RayPooley]

The PRV I am referring to is the pressure reducing valve, the cylinder PRV is the pressure relief valve (safety valve) the other PRV that you refer to is probably the expansion valve and as its set to 4.5bar it might lift if you set the EV prechargeto 3bar. Have you got a pressure reducing valve installed? and if so check its setting.

Ah. The one in the combination valve. Got it. There are 3 valves in total then.
Two in the combination valve. A PRV at 4.5 bar (blue cap) and the reducing valve which connects to the supply.
I presume that's limited to the supply pressure or there about.
One PRV in the tank at 6 bar.

 

[RayPooley]

Are you g3 registered as your working on an unvented?

I'm not. But the guy who is supervising the job is.

 

[ShaunCorbs]

I'm not. But the guy who is supervising the job is.

And what does he say set the pre charge to ? Also why are you changing an expansion vessel on an newer cylinder?