CH pressure dropping - leak or PRV?

[749s]

Hi

I've got a Valiant something boiler that heats an unvented system.

The pressure is dropping every fortnight to below 0.5 bar and then the boiler cuts out. It seems to only need a small top up from the loop to take the pressure back up again.

Searching this forum suggests it could be as simple as a PRV ( I can't see any obvious leaks).

THoughts? If it is this - where would I find it?

If it's not - how do I fix a leak I can't see??

Many thanks.

 

[Burnerman]

If the PRV is letting water by, it will be visible outside.....tie a poly bag over the pipe and see if water collects.
If its not that, well it could be within the boiler itself (automatic air vent maybe) or anywhere on the external radiator pipework or valves.
Further tests could involve isolating the boiler from the pipework via its shut off valves - if the pressure drops then, the fault is internal.
John

 

[749s]

If the PRV is letting water by, it will be visible outside.....tie a poly bag over the pipe and see if water collects.
If its not that, well it could be within the boiler itself (automatic air vent maybe) or anywhere on the external radiator pipework or valves.
Further tests could involve isolating the boiler from the pipework via its shut off valves - if the pressure drops then, the fault is internal.
John

Thanks John.

I think I'll get the pro's in, in that case.

It's reassuring to know it's not neccessarily a leak.

 

[Burnerman]

I'm afraid there is, unfortunately somewhere........!
John