Our Performa is about 3 years old and has suddenly lost pressure. There is no evidence of any leaks. Does anyone have any suggestions about how or why and if so how we can remedy?
No pressure - Performa 28i
- Thread starter TheSproules
- Start date
When you say no leaks do you mean just internally on your ch system? Have you checked outside for water or drips coming out of the prv?
To lose pressure suddenly then the boiler must have overpressurised due to a fault of some sort and the prv activated to make safe. repressurise to about 1.2 bar cold and run boiler and see if pressure gauge rises very quickly. If so could be that expansion vessel needs recharging or it could have split internally and needs replacing. Could be other faults so you need to post more accurate info of the problem and when it is occuring etc.
To lose pressure suddenly then the boiler must have overpressurised due to a fault of some sort and the prv activated to make safe. repressurise to about 1.2 bar cold and run boiler and see if pressure gauge rises very quickly. If so could be that expansion vessel needs recharging or it could have split internally and needs replacing. Could be other faults so you need to post more accurate info of the problem and when it is occuring etc.
We can not find any leaks inside nor is there evidence of leaks from the PRV vent outside.
We have now run the heating on boost and the pressure builds up to about .8 bars. The heating is working fine when it is on boost and when we run the hot water the pressure falls back to .5 bar but comes back up to .8 when we stop.
How long should we leave the boost on for? Is there another way to re-pressurise?
We have now run the heating on boost and the pressure builds up to about .8 bars. The heating is working fine when it is on boost and when we run the hot water the pressure falls back to .5 bar but comes back up to .8 when we stop.
How long should we leave the boost on for? Is there another way to re-pressurise?
Thee should be a flexible filling loop under the boiler or near it. Probably flexible chrome or silver looking about 300mm long, will have a 'washing machine' type tap either end. just open both these taps and let the pressure guage build up to aroung 1-1.2 bar when rads are cold or about 1.8 if hot. You may have to look for the filling loop if it is not connected to the isolating taps and just fit it on yourself first 
Thanks Dave,
I have tried opening both of these valves with the heater boost on and off but the pressure does not rise more than 0.8 bar. We also have a valve at one end of the flexi pipe which I have tried opening and closing as well with no real effect. Not sure where to go from here?
With the heating boost off the pressure is hanging in there at .5 bar. It drops down to about .2 when I run the hot water but does come back up?
I have tried opening both of these valves with the heater boost on and off but the pressure does not rise more than 0.8 bar. We also have a valve at one end of the flexi pipe which I have tried opening and closing as well with no real effect. Not sure where to go from here?
With the heating boost off the pressure is hanging in there at .5 bar. It drops down to about .2 when I run the hot water but does come back up?
It sounds as if the gauge may be faulty or you have a serious lack of supply pressure.
You may need to get professional help.
You could see if there is a good flow by taking the boiler end of the filling loop off and filling a bucket but thats only half the story.
You could measure the pressure in the mains if you had a gauge.
Tony
You may need to get professional help.
You could see if there is a good flow by taking the boiler end of the filling loop off and filling a bucket but thats only half the story.
You could measure the pressure in the mains if you had a gauge.
Tony
Cheers.
Thank you everyone for your help. Managed to get enough hot water for a couple of showers. It does seem like there is something more sinister if we can't get the pressure to build up? Mght seek professional help tomorrow.
Thank you everyone for your help. Managed to get enough hot water for a couple of showers. It does seem like there is something more sinister if we can't get the pressure to build up? Mght seek professional help tomorrow.
TheSproules said:
Keep the heating off and let heating go cold so it drops to its minimum pressure. Then turn on the valve at each end of the flexi pipe together. You should be able to see pressure rising. Haveyou done as Tony suggest running it into a bucket to check supply flow and pressure? Are you sure that the filling loop valves are actually opening. If they are the 'washing machine type' it is very commom for the plastic head to split so when you turn it all it does is turn around the spindle rather than open it. Try taking plastic head off and turning with some grips.
What is the hot tap pressure like? as this is usually fed from the same cold supply that the filling loop is teed into. You may also have a jammed non-return valve in the filling loop (the longer connection end).
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
