worcester 30si boiler problem

[Nicko131187]

hi, im having trouble with a worcester 30si combi boiler, the pressure keeps dropping after 24 hours and having to re pressurise the system in order for it to work again, water is constantly dripping from the pressure relief valve pipe on the outside of the propertie where it exits, i have changed the valve as thought it might be the problem, the pressure when the boiler is on is about 1.5 bar, and doesnt go up when boiler is on so it cant be the expansion vessel. after changing the blow off this problem still occurs.
any help would be great as problem with customer needs solving
Many thanks

 

[anz]

You've changed the pressure relief valve and its still passing?

 

[stevetheplumber]

are you sure the gauge is working ? id isolate the boiler and drain to se if the gauge is stuck unless your very unlucky a new prv shouldnt pass at 1,5bar

 

[Nicko131187]

Yehh tested the gauge, as the old prv was being replaced i drained it by it to see if the gauge was working, and its fine. If the boiler was over pressurising and blowing off i would make sure the expansion was charged or the diaphram in tact but when the boiler runs it doesnt exceed 1.8 bar. You think the new prv may be also faulty? i cant think it could be anything else. Its wierd as all it is is a constant dri0.
Many thanks

 

[Billy Bob Bob]

expansion vessel knackerd or flexible link blocked

 

[tamz]

If the new prv is passing and system pressure is in order then the valve MUST be faulty. Take it back.