Central Heating Leak
Discussion
Afternoon all,
I have a leak in my central heating system that I’m trying to trace. Before I start removing floor coverings and lifting floor boards I want to be absolutely sure the leak isn’t from the gas boiler itself. So far I have checked the following.
1. There is no water flowing through the PRV and the pipe that exits through the external wall is dry so I’m assuming that the PRV is working correctly.
2. The heating engineer could not see any leaks from the expansion vessel or the heat exchanger within the boiler.
3. There is no condensate water as far as I can see.
The boiler is an Ideal Logic+ 24kW System Boiler installed a year ago – its getting its annual service on Friday. I’m losing about 0.5 bar of pressure each day so constantly having to top up the boiler via the filling loop to ensure that we have heat and hot water each day.
There are no signs of water leaks at any of the radiator connections and I can’t see any damp patches on ceilings or floors so I’m guessing the leak might be below the ground floor. The house is approx. 25 years old with a timber suspended ground floor approx. 300-400mm above the external ground level. There won’t be enough crawl space to get below the floor to check all the pipework so I will have to remove floorboards at each radiator location to start with to try and find the leak.
The last check I want to do is to isolate the boiler from the rest of the central heating system My understanding is that if I close the flow and return valves on the pipework feeding the boiler this will isolate the boiler from the rest of the system. If I set the pressure to say 1.2bar and close both valves, how long should I leave it like this to monitor for any pressure drop? Will a few hours be enough? I’m assuming I should NOT run the boiler whilst the valves are closed?
When the heating is on all radiators are hot and I have bled the radiators to remove any air.
Thanks in advance for any advice / guidance.
I have a leak in my central heating system that I’m trying to trace. Before I start removing floor coverings and lifting floor boards I want to be absolutely sure the leak isn’t from the gas boiler itself. So far I have checked the following.
1. There is no water flowing through the PRV and the pipe that exits through the external wall is dry so I’m assuming that the PRV is working correctly.
2. The heating engineer could not see any leaks from the expansion vessel or the heat exchanger within the boiler.
3. There is no condensate water as far as I can see.
The boiler is an Ideal Logic+ 24kW System Boiler installed a year ago – its getting its annual service on Friday. I’m losing about 0.5 bar of pressure each day so constantly having to top up the boiler via the filling loop to ensure that we have heat and hot water each day.
There are no signs of water leaks at any of the radiator connections and I can’t see any damp patches on ceilings or floors so I’m guessing the leak might be below the ground floor. The house is approx. 25 years old with a timber suspended ground floor approx. 300-400mm above the external ground level. There won’t be enough crawl space to get below the floor to check all the pipework so I will have to remove floorboards at each radiator location to start with to try and find the leak.
The last check I want to do is to isolate the boiler from the rest of the central heating system My understanding is that if I close the flow and return valves on the pipework feeding the boiler this will isolate the boiler from the rest of the system. If I set the pressure to say 1.2bar and close both valves, how long should I leave it like this to monitor for any pressure drop? Will a few hours be enough? I’m assuming I should NOT run the boiler whilst the valves are closed?
When the heating is on all radiators are hot and I have bled the radiators to remove any air.
Thanks in advance for any advice / guidance.
Rent or buy a thermal camera.You can get a FLiR1 camera that attaches to an iPhone for a couple of hundred quid.
Get the heating really hot and circulated and then look around, you may see a blush where it is leaking.
Or get a company to come and do a thermal survey.
Either will be far cheaper than just randomly taking up boards.
We had a water leak at the weekend. I used a FLir on my iPhone, located the leak and marked the area with an X. The plumber cam and took just a small section of floor up right over it and repaired the pipe. So much easier when you know exactly where it is!.
Get the heating really hot and circulated and then look around, you may see a blush where it is leaking.
Or get a company to come and do a thermal survey.
Either will be far cheaper than just randomly taking up boards.
We had a water leak at the weekend. I used a FLir on my iPhone, located the leak and marked the area with an X. The plumber cam and took just a small section of floor up right over it and repaired the pipe. So much easier when you know exactly where it is!.
The FLiR1 is a great bit of kit!
If you haven't got one then you will have to be systematic.
Hopefully you have upstairs and downstairs zones on separate motorised valves.
0.5 bar drop per day is significant and you should have already seen the wet stains on the ceiling if one of the upstairs is leaking.
Just to make sure you need to just run up or down for half a day whilst turning off the radiators in the other zone (hopefully you have TRV's). By process of elimination you should be able to get close to the leak.
If you haven't got one then you will have to be systematic.
Hopefully you have upstairs and downstairs zones on separate motorised valves.
0.5 bar drop per day is significant and you should have already seen the wet stains on the ceiling if one of the upstairs is leaking.
Just to make sure you need to just run up or down for half a day whilst turning off the radiators in the other zone (hopefully you have TRV's). By process of elimination you should be able to get close to the leak.
I had a leek that was needing a top up every couple of days. I really didn’t want to start taking up floors etc
In my daughter’s room we were decorating and decided to replace her radiator with a new one. There must have been a leek on that or very localised to it, replaced it and it stopped leaking
Perhaps isolate radiators one by one in the hope you have the same issue as me
In my daughter’s room we were decorating and decided to replace her radiator with a new one. There must have been a leek on that or very localised to it, replaced it and it stopped leaking
Perhaps isolate radiators one by one in the hope you have the same issue as me
Ecosseven said:
Afternoon all,
The last check I want to do is to isolate the boiler from the rest of the central heating system My understanding is that if I close the flow and return valves on the pipework feeding the boiler this will isolate the boiler from the rest of the system. If I set the pressure to say 1.2bar and close both valves, how long should I leave it like this to monitor for any pressure drop? Will a few hours be enough? I’m assuming I should NOT run the boiler whilst the valves are closed?
A 0.5 bar loss is quite a lot. My boiler was doing similar a few years ago, turned out the primary heat exchanger was cracked, water from the central heating side was dripping out through the condensate pipe. Don't know what it's like on your boiler, but on my Worcester I just removed the condensate bowl and placed a bucket underneath whilst the boiler was isolated (as above) and collected about 100ml in an hour. The last check I want to do is to isolate the boiler from the rest of the central heating system My understanding is that if I close the flow and return valves on the pipework feeding the boiler this will isolate the boiler from the rest of the system. If I set the pressure to say 1.2bar and close both valves, how long should I leave it like this to monitor for any pressure drop? Will a few hours be enough? I’m assuming I should NOT run the boiler whilst the valves are closed?
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