Hello,
The pressure in my heating system rises from 0.5 bar to over 2 bar when the system is hot. And can drop from 1 bar to 0.5 and down to zilch in half a day!
I had initially noticed that the system was losing pressure and had to top up frequently (every few days). I initially changed the PRV and subsequently the expansion vessel as it would appear the diaphragm had gone in the old one. My assumption was that the old one had gone and subsequently the system was over pressurising when hot thus releasing through the PRV etc.
However, since changing the expansion vessel the system pressure has still been dropping which would imply a leak - I have found a small leak on the valve just before the pump (expansion vessel is t'eed into system -> pump -> boiler) and plastic bag has caught about 30ml in 24 hours so definately needs sorting but why would the system be gaining so much pressure when on?
Could air be being sucked into the system and causing issues?
Would sludge in the system cause these issues?
Today I topped up this morning to 1 bar. System got hot and rose to over 2 bar. When system sw cold pressure as 0.5 bar (lost half a bar) and when switched on again rose back to over 2 bar??
I think that one question at the minute is even with low starting pressure why would the operating pressure still rise to over 2 bar?
I can't find any other leaks but by my calculations I could be losing up to half a litre per day which is a little worrying! The boiler is a potterton profile 80. The is no obvious water in the boiler and the system does appear to lose some pressure when cold which wouldn't get instantly evaporated away.
Any thoughts before I get the professionals in?
Any help much appreciated.
Thanks,
David
The pressure in my heating system rises from 0.5 bar to over 2 bar when the system is hot. And can drop from 1 bar to 0.5 and down to zilch in half a day!
I had initially noticed that the system was losing pressure and had to top up frequently (every few days). I initially changed the PRV and subsequently the expansion vessel as it would appear the diaphragm had gone in the old one. My assumption was that the old one had gone and subsequently the system was over pressurising when hot thus releasing through the PRV etc.
However, since changing the expansion vessel the system pressure has still been dropping which would imply a leak - I have found a small leak on the valve just before the pump (expansion vessel is t'eed into system -> pump -> boiler) and plastic bag has caught about 30ml in 24 hours so definately needs sorting but why would the system be gaining so much pressure when on?
Could air be being sucked into the system and causing issues?
Would sludge in the system cause these issues?
Today I topped up this morning to 1 bar. System got hot and rose to over 2 bar. When system sw cold pressure as 0.5 bar (lost half a bar) and when switched on again rose back to over 2 bar??
I think that one question at the minute is even with low starting pressure why would the operating pressure still rise to over 2 bar?
I can't find any other leaks but by my calculations I could be losing up to half a litre per day which is a little worrying! The boiler is a potterton profile 80. The is no obvious water in the boiler and the system does appear to lose some pressure when cold which wouldn't get instantly evaporated away.
Any thoughts before I get the professionals in?
Any help much appreciated.
Thanks,
David