intermittent discharge from the PRV from my Vokera28

[ChrisinFife]

the problem only occurs when the heating is on OVO engineer came and declared it to be a choked heat exchanger and choked hoses, he cant do anything as the insurance doesnt cover sludge. I'm sceptical as there is no shortage of heating, but there is a reduction in hot water temp. My view is that it is almost certainly a cracked tube (?) in the heat exchanger.
I'm happy to change the internal hoses myself, which he hinted was the solution, but dont want to do it if they are liable for a new heatex.

 

[ShaunCorbs]

Does the boiler overheat ?

Also when was the expansion vessel last checked when there’s no water in the boiler

Get the ovo / corgi engineer back on a recall and prove to you it’s sludge also the prv doesn’t just fail because of sludge

 

[SJB060685]

As Shaun says a PRV lifts/discharges when the water system pressure exerts enough force on the valve spring to open the valve. It’s much more likely due to the vessel having little to no charge and any engineer touching boilers should have considered and checked this before making such as statement as it’s sludge related. You could still have a sludge problem yes but the PRV lifting is almost certainly caused by something else.