Baxi 105e - Heating but no hot water

[harpercr]

Apologies for the mixup - its only when I looked at the photo I realised it was a Instant - I've done most of these posts at work, so had to rely on the manual I downloaded ages ago!

So if the pressure going up is another fault - what would be doing that?

Thanks for your help Ian.

 

[45yearsagasman]

With heating on it is not unusual for the pressure to rise from 1 to 2bar. As long as the PRV is not dripping and when cold, the system goes back down to 1bar, it would appear to be normal.
Don't go looking for faults that may not be there, and fit the diaphragm as you have been advised to do.

 

[ianmcd]

if it isnt going higher than 2 Bar then I wouldnt worry about it , just mention this to the engineer next time you have your boiler serviced, this has nothing to do with your HW problem, if anything the pressure problem just needs a bit of maintenance work done during a proper service and nothing to do with the pressure releif valve that you mentioned