Hi there,
I have a Worcester Bosch Greenstar 36CDi combi boiler. Over the past 9 months I've noticed that the pressure gradually increases in the system and I have to regularly remove water from a radiator to reduce the pressure back down to 1 bar. It has gone up as high as 2.75 bar....eek!
I have drained the boiler and re-pressurised the expansion vessel to 0.75 bar and I noticed the pressure stayed reasonably stable for a time but then it started to creep up again.
I did the re-pressurisation at the tail end of winter at a point when the boiler is rarely used to heat the house (it's only use outside of winter is for hot water for showers) so maybe the pressure increase is directly related to the how frequently the boiler is used.
One possible cause that I read about is that if the filling loop was letting mains water slowly into the heating circuit. So when I was away for recently for 10 days, and the boiler wouldn't have been in use, I noted the pressure before and after and there was no change. This indicates the filling loop not being completely closed is less likely to be fault.
Another possible cause could be a problem with the expansion vessel, however I thought that the pressure would change significantly when the system is hot vs when it's cold and this does not seem to be the case.
Would anyone have any ideas? Thanks
I have a Worcester Bosch Greenstar 36CDi combi boiler. Over the past 9 months I've noticed that the pressure gradually increases in the system and I have to regularly remove water from a radiator to reduce the pressure back down to 1 bar. It has gone up as high as 2.75 bar....eek!
I have drained the boiler and re-pressurised the expansion vessel to 0.75 bar and I noticed the pressure stayed reasonably stable for a time but then it started to creep up again.
I did the re-pressurisation at the tail end of winter at a point when the boiler is rarely used to heat the house (it's only use outside of winter is for hot water for showers) so maybe the pressure increase is directly related to the how frequently the boiler is used.
One possible cause that I read about is that if the filling loop was letting mains water slowly into the heating circuit. So when I was away for recently for 10 days, and the boiler wouldn't have been in use, I noted the pressure before and after and there was no change. This indicates the filling loop not being completely closed is less likely to be fault.
Another possible cause could be a problem with the expansion vessel, however I thought that the pressure would change significantly when the system is hot vs when it's cold and this does not seem to be the case.
Would anyone have any ideas? Thanks
