Ferroli 701 Optima Water leak through 3 bar pressure valve

[Cap]

I have a Ferroli 701 Optima which leaks water through its CH 3 bar safety pressure valve. The water pressure is at 1 to 2.5 bar but still the water leaks out onto the roof all the way down to zero pressure.
I have replaced the safety valve twice but still the same problem.
Any ideas?
Cap

 

[gas4you]

When is it leaking? All the time even when boiler off? when h/w on, when ch on or both?

 

[gas4you]

When is it leaking? All the time even when boiler off? when h/w on, when ch on or both?

 

[alkalinepantera]

the expansion vessel is probably at fault. no air in it.

 

[Cap]

When is it leaking? All the time even when boiler off? when h/w on, when ch on or both?

It looks to leak more/only when the C/H is on and the taps in the kitchen and shower drip when the C/H goes off I think.
I have just tested the H/W and have no drips from the boiler.
I have now set the C/H to run and have had no drips. The boiler has cut off at 72Deg C and still no drips from the boiler, the shower is not dripping but the kitchen sink is.
these two taps team up and drip together or cut off as what ever happens, happens.
??????????????????????????????????
Cap

 

[gas4you]

Dripping kitchen or bath taps will not affect the pressure drop from the prv. This will be a system fault.

As already suggested in another reply, check that expansion vessel is pressurised to around 1 bar (16psi approx) befoe anything else.

 

[Cap]

I will give it a go and let you know.
Thanks Both
Cap