baxi 105e

[gymdad]

just changed expansion vessel and prv to solve an increase of pressure, filling loop not by passing but pressure is still increasing even c/h is off could this be main heat exchanger

 

[SafeGasInstall]

was boiler sludged up ? did you check pressure on new ex v

 

[Billy Bob Bob]

if you have ruled out ev,prv,and filling loop your plate heats pinholed

 

[casaco]

Turn off cold feed to boiler, if pressure stops increasing then gas man is probably right, plate to plate pin holed.

 

[RoryD]

Either the plate to plate has pinholed or the pipe coming out of the bottom of the expansion vessel is blocked (quite common)

 

[casaco]

If the pipe is blocked, the prv normally blows off. water has no where else to go.

 

[RoryD]

If the pipe is blocked, the prv normally blows off. water has no where else to go.

yes it will... eventually, but it will eventually if the plate to plate pinholes, changed one 2 days ago for same thing. It doesn't have to be a catastrophic blow off, it sometimes releases as a constant slow flow / drip