vaillant pressure problem

[darrenbea]

Hi
Got a few issues with a Vaillant TurboMax plus 824e combi. i filled the system up to1.5 bar and checked the expansion vessal it got 0.7 bar pressure. leave it 24 hrs and the pressure goes to above 3bar and passes though the pressure relief valve got no m.i's to check

Any advice appreciated.
darren😱

 

[Toddyplumb]

Are you gas safe registered ?

 

[tackleburger]

You have either a bust expansion vessel or it needs re-charged either way it really is a job for a GSR fitter.

Sorry should read the post properly. If the vessel has the correct charge and is holding you either have a passing filling loop which you can disconnect and check. If not most likely the DHW heat exchanger has a pinhole in it the later ought to be done by a qualified person.

 

[aggis]

Expansion vessel recharging should be done with boiler drain open and drained down. Pressure about 10 -14 psi depending on size of system, also worth checking feed tube to exp vessel not blocked. These prob's will only cause it to reach 3bar & blow off when using heating.
If boiler totally off for 24hrs & pressure goes up to 3bar it's filling loop or mains water getting into heating via w/w or internal seal leaking

 

[darrenbea]

many thanks i am gas safe registered but nomally only install/services not repair as times are quiet i im getting more calls from people trying to fix there boiler not replacing them