Fluctuating combi pressure

[GinGaz]

Have started needing to top up pressure every couple of days to keep it at 1bar although it never drops to zero or locks out. Today though I noticed its doing the old 1bar to 2.0- 2.3 swing in pressure.
I have had a rubber glove tied over the PRV outlet and so far nothing ... could it still be expansion vessel related?
Its only been about 5 months since the Worcester engineer recharged it (he said it was completely flat)

 

[denso13]

could it still be expansion vessel related?

It could be. You won't get anything at the PRV outlet unless it goes above 3 bar (normally).

 

[jeff the gasman]

If climbing with no demand either filling loop is passing or plate perforated.