Any Central Heating Experts??
Discussion
HI there
Problem with central heating. Boiler is a condensing combi. Losing water pressure on gauge at boiler.If I top it up via the filling loop, the system works fine, as long as the boiler is on. It's when it shuts down that the pressure seems to bleed away. The boiler still works with the pressure gauge at or around zero. According to the manual there is a pressure switch to inhibit the start if the pressure is low, so, either this does not work or the pressure is not THAT low. If I top it up to say 1/2Bar then when the pump kicks in the pressure goes up to around 1Bar. I would have thought that at double the pressure, the leak would have been more evident, and lose pressure quicker. No obvious leaks above floor, so problem is either underneath or in the boiler.I DO get air in a couple of the rads.When I top up with the filling loop there is water going in, so obviously there is water coming out somewhere along the line.
The point of this post is to try and ascertain if I have a boiler problem before I have to start ripping the floor up.
The boiler is under guarantee. Would it be wise to get them out first to check all is ok before going down the pipework leak road?
Are there any simple checks I can do to isolate the problem further? Not sure how I can find a leak without eyeballing every bit of pipe. There is a valve each side of the filling loop, but not sure there is any other way of isolating the fault.
Have already tried pumping in leak sealer to no avail.
Any advice would be most welcome.
Thx in advance
Phil
Problem with central heating. Boiler is a condensing combi. Losing water pressure on gauge at boiler.If I top it up via the filling loop, the system works fine, as long as the boiler is on. It's when it shuts down that the pressure seems to bleed away. The boiler still works with the pressure gauge at or around zero. According to the manual there is a pressure switch to inhibit the start if the pressure is low, so, either this does not work or the pressure is not THAT low. If I top it up to say 1/2Bar then when the pump kicks in the pressure goes up to around 1Bar. I would have thought that at double the pressure, the leak would have been more evident, and lose pressure quicker. No obvious leaks above floor, so problem is either underneath or in the boiler.I DO get air in a couple of the rads.When I top up with the filling loop there is water going in, so obviously there is water coming out somewhere along the line.
The point of this post is to try and ascertain if I have a boiler problem before I have to start ripping the floor up.
The boiler is under guarantee. Would it be wise to get them out first to check all is ok before going down the pipework leak road?
Are there any simple checks I can do to isolate the problem further? Not sure how I can find a leak without eyeballing every bit of pipe. There is a valve each side of the filling loop, but not sure there is any other way of isolating the fault.
Have already tried pumping in leak sealer to no avail.
Any advice would be most welcome.
Thx in advance
Phil
This slow leaks can be an ar5e to find. First thing is to check all the radiator trvs and valves. Its not unheard to have a weeping valve and the heat evaporates the water off. Wrapping the valves with tissue will tell if these are leaking. The alternative is that a joint may have split, so check the ones you can see. These issues are a pita to find without evidence showing. Providing your mains pressure is not too high, you could try leaving the filling loop open and waiting for a damp patch to appear...
Is water escaping from the safety relief pipe outside when it heats up??
If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
Edited by Ferg on Saturday 31st January 08:55
Ferg said:
Is water escaping from the safety relief pipe outside when it heats up??
If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
In my experience about 90% of these problems stem from a pressure vessel that has lost its charge, or the membrane has ruptured.If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
Edited by Ferg on Saturday 31st January 08:55
dirkgently said:
Ferg said:
Is water escaping from the safety relief pipe outside when it heats up??
If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
In my experience about 90% of these problems stem from a pressure vessel that has lost its charge, or the membrane has ruptured.If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
Edited by Ferg on Saturday 31st January 08:55
dirkgently said:
Ferg said:
Is water escaping from the safety relief pipe outside when it heats up??
If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
In my experience about 90% of these problems stem from a pressure vessel that has lost its charge, or the membrane has ruptured.If the pressure vessel has ruptured there is no provision for expansion and it may be pushing the water out of the safety. When it cools it will quickly disappear due to the contraction of the water volume.
Don't rule out a faulty gauge either.
Edited by Ferg on Saturday 31st January 08:55
Hi again
Just an update.
Contacted the boiler guarantee people, at risk of being charged if there was no boiler fault.Decent chap appeared, took it to bits and found the heat exchanger bust and leaking. The reason I had never seen it is that the leaking water runs down the condensate drain, which joins in with the washing machine etc, and not out the main boiler drain.
He is also replacing the pump while he is there. (Decent chap as I said!!)
Glad of guarantee. Cost is £177 for heat exchanger + £83 for pump. All plus call-out and labour. So probably the guts of 400 big ones.
Also glad it's the boiler, wasn't looking forward to ripping the floors up!!!
Cheers
Phil
Just an update.
Contacted the boiler guarantee people, at risk of being charged if there was no boiler fault.Decent chap appeared, took it to bits and found the heat exchanger bust and leaking. The reason I had never seen it is that the leaking water runs down the condensate drain, which joins in with the washing machine etc, and not out the main boiler drain.
He is also replacing the pump while he is there. (Decent chap as I said!!)
Glad of guarantee. Cost is £177 for heat exchanger + £83 for pump. All plus call-out and labour. So probably the guts of 400 big ones.
Also glad it's the boiler, wasn't looking forward to ripping the floors up!!!
Cheers
Phil
Hi Ferg
It's an Ariston ACO 32MFFI. Luckily they give out a 5 year guarantee when you buy them. I'm now in year 4 of 5.
Now I know what the problem is, it all makes sense.I was losing pressure on the gauge and then topped it up using the filling loop. But I was only getting a small whiff of air out of the radiator vent.The boiler is the highest point and the air finished up in the boiler heat exchanger via the leak.
As I said, I'm just pleased it is actaully the boiler and not some obscure leak under the floor.
Cheers
Phil
It's an Ariston ACO 32MFFI. Luckily they give out a 5 year guarantee when you buy them. I'm now in year 4 of 5.
Now I know what the problem is, it all makes sense.I was losing pressure on the gauge and then topped it up using the filling loop. But I was only getting a small whiff of air out of the radiator vent.The boiler is the highest point and the air finished up in the boiler heat exchanger via the leak.
As I said, I'm just pleased it is actaully the boiler and not some obscure leak under the floor.
Cheers
Phil
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