i have a potterton 24 he plus system losing pressure. during summer when radiators not in use pressure is fine but as soon as we start using the rads pressure drops and needs topping up daily. pressure only drops when rads have heated up and we turn the thermostat down. if we had heating on all day no pressure would be lost (v expensive). have had new pressure relief valve fitted, no sign of any leaks and this has been happening for a long time any ideas please?
potterton 24 he plus system losing pressure
- Thread starter abbey39
- Start date
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Or is undersized
You cannot often visit London!
Property in London is mostly very small!
I dont remember when I last visited a house larger than mine! ( 5 B det in 1/2 acre )
Nearly everything is two bed flat or smaller with a few small terraced and semi houses with three small bedrooms.
Such is the difficulty of increasing property prices starting at £200k and reducing salaries and the trend for people not to get married but to live alone or with a friend.
Tony
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Thanks for your response. if i top up the system and do not use the central heating system and it still still loses pressure would that indicate that we have a leak? or does not using the central heating system not make a difference to the expansion vessel? sorry if silly question but have no idea how the system works.
If you set the pressure to 1.5 Bar cold and the expansion vessel is failed or not pressurised then, on heating up the radiators, the water expands.
The resultant pressure increase causes the pressure relief valve ( PRV ) to open and allow water out.
It will then run for that heating session at a pressure of about 2.5 bar after the PRV closes.
After cooling down there is no significant pressure left in the boiler so you will top it up again if you notice it.
Some boilers have a low water pressure switch and that stops the boiler from working again until its topped up. ( Not yours though. )
Tony
The resultant pressure increase causes the pressure relief valve ( PRV ) to open and allow water out.
It will then run for that heating session at a pressure of about 2.5 bar after the PRV closes.
After cooling down there is no significant pressure left in the boiler so you will top it up again if you notice it.
Some boilers have a low water pressure switch and that stops the boiler from working again until its topped up. ( Not yours though. )
Tony
if you top up the pressure and turn the boiler off for 24hours, if pressure drops you have a leak - may be prv especially if its vented off a few times recently, if not it will most likely be expansion vessel.
However you may have both of these problems!!
However you may have both of these problems!!
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