worcester 38CDI pressure drops to 0 when shower run

[plumb_know]

Hi Everyone,


Customer has worcester 38cdi that keeps going up to 4bar pressure, i replaced the expansion vessel as no pressure & water out of shrader, i also checked the expansion pipe for debris & replaced AAV as was not working.

week has passed and customer has said gauge gone back to 4bar but drops to 0 when shower is run, could this signal a split in the plate heat exchanger??

Thanks

 

[ShaunCorbs]

Plate . Z . Z

 

[plumb_know]

Shaun sorry mate i might be being thick i do not know .Z .Z means??

 

[ShaunCorbs]

Shaun sorry mate i might be being thick i do not know .Z .Z means??

Need 5 words for the post count thing

 

[Burger]

Out of interest, has the filling loopbeen checked for it passing?

 

[plumb_know]

Haha thought it might have been a welsh thing

the filling loop was passing to begin with but i pushed jumper up on it and it seemed to shut off. If it was staying at 4bar i would be looking at this more but cant see why it would drop to 0 when hot water used as will have check valve to stop back flow??