I have a Vaillant combi bolier (about 10 years old) with the pressure guage jumping to the max all the time. I have to use the pressure release tap to release the excess water once every week or even every two days!

I know the pressure represents the amount of water store inside the boiler, so is it a problem with my top-up tap that slowly letting excess water into the boiler or is it something else?

Thanks for any help or suggestions.

Good Morning.

Gauge pressure reading relates to height of water in pipes above. What
you describe happening could be caused by failure of expansion tank or
of pressure-regulating fill-valve. Or both.

To diagnose and fix, I'd suggest you contact a competent plumber.

HTH,
John

Opuscm wrote:
I have a Vaillant combi bolier (about 10 years old) with the pressure
guage jumping to the max all the time. I have to use the pressure
release tap to release the excess water once every week or even every
two days!

I know the pressure represents the amount of water store inside the
boiler, so is it a problem with my top-up tap that slowly letting
excess water into the boiler or is it something else?

Thanks for any help or suggestions.


--
Opuscm