Central Heating - Major Leak

airman737

Hello All

I have a major leak in my CH System. It is ongoing for the past 5 weeks. There are no signs of water or dampness in the house, so I investigated outside, only to find that the leak is coming frominside the house (Water can be seen dripping from the foundation outside the back door. I called in water leak detectors, but they were unable to find the leak, as they could not pressurize the system :-(, So I'm back to square 1. I'll list what I know:

1. I have no small water tank in the attic. My central heating feed comes from the big water tank. When I open the valve in the attic, the tank will empty within 5 minutes (250 Litres).

2. There is no signs at all of any water leak in the ceilings or walls upstairs.

3. According to the leak detection people, all my radiators are empty.

4. When I switch the oil burner on, it will run for about 2 minutes then switch off. I have no heat in the rads or hot tank in the attic.

Any advice would be grately appreciated. I have had 2 plumbers let me down (By not calling to me). Maybe they think it;s too messy a job to deal with (That's the impression i'm getting)

shane0007

Firstly do not run the boiler without water in it. It could buckle the boiler.
It is a very substantial leak so it really shouldn't be that hard to trace, especially when you can see water. The leak is obviously under the floor close to the back door so that's the starting point.
It will be a matter of investigation, compressor with air & trying to listen & breaking floors.
Worse case, get in a person with sonic listening device, but a decent plumber should be able to trace.

anthonyos

I know a old plumber who uses his bare feet to find leaks by walking around till he finds a hot spot

Dtp1979

anthonyos wrote: »

I know a old plumber who uses his bare feet to find leaks by walking around till he finds a hot spot

Fcuk that's old school!

anthonyos

I know that's how he found a leak in my uncles house is the compressed air method any good for finding leaks

airman737

shane0007 wrote: »

Firstly do not run the boiler without water in it. It could buckle the boiler.
It is a very substantial leak so it really shouldn't be that hard to trace, especially when you can see water. The leak is obviously under the floor close to the back door so that's the starting point.
It will be a matter of investigation, compressor with air & trying to listen & breaking floors.
Worse case, get in a person with sonic listening device, but a decent plumber should be able to trace.

Thanks for the reply Shane. I had the builder of the house in at the weekend and he said the same, that if the water is dripping outside the back door, I should start there. Hopefully I get a plumber soon just to get an expert opinion.

airman737

anthonyos wrote: »

I know that's how he found a leak in my uncles house is the compressed air method any good for finding leaks

I actually have a compressor, how would I go about using it does anyone know?

jimf

airman737 wrote: »

Thanks for the reply Shane. I had the builder of the house in at the weekend and he said the same, that if the water is dripping outside the back door, I should start there. Hopefully I get a plumber soon just to get an expert opinion.

What area are u in maybe one the lads on here may be able to help

esox28

Have you any photos of the pipework layout form the time the house was being built?

Can you get in touch with the original plumber maybe he might have some suggestion as to where pipework is.

Get your insurance assement done as soon as.

You're going to have to kango the floors to get at the pipe, so what you need to do is limit the damage by finding out as much info as possible, try to narrow the leak down to as small an area as possible. There's no need to compress the system but if you hire a 100-150 ltr compressor so you can send as much air as possible (without having the thing running) then listen to narrow the area down.

Shane have you used that ir camera to leak find at all?

shane0007

I would isolate upstairs & hot water circuits. Then tee into down stairs, blanking pipework from rest of system. Remove auto air vents & blank. Build pressure or if it cannot keep up with the leak, leave compressor on. Start as close as possible to the back door where water is visible.

The issue here would be with up such a leak, I would doubt if the system would ever get hot enough if it is leaking 250L in a few minutes. That's a fireman's hose leak! Compressed air can usually be heard hissing.

shane0007

esox28 wrote: »

Shane have you used that ir camera to leak find at all?

Yes on many occasions but unless the system can be got hot, the camera is not so good unless there is a temperature difference or staining. Wooden floors can affect the visuals also as timber is a good insulator. Best on tiled floors.

With such a leak as the OP, IMO the best option would be a compressor or sonic listening would find it within minutes.

airman737

esox28 wrote: »

Have you any photos of the pipework layout form the time the house was being built?

Can you get in touch with the original plumber maybe he might have some suggestion as to where pipework is.

Get your insurance assement done as soon as.

You're going to have to kango the floors to get at the pipe, so what you need to do is limit the damage by finding out as much info as possible, try to narrow the leak down to as small an area as possible. There's no need to compress the system but if you hire a 100-150 ltr compressor so you can send as much air as possible (without having the thing running) then listen to narrow the area down.

Shane have you used that ir camera to leak find at all?

The plumber who laid the pipes has emigrated to australia, but the builder seemed to have a fair idea where the pipes are going. I rang insurance company, they said i'm not covered as the water hasn't caused any damage.

airman737

jimf wrote: »

What area are u in maybe one the lads on here may be able to help

I'm in Co. Longford

esox28

Get a private insurance assessment done afaik the leak will cause damage to trace and repair.
But its up to yourself as most policies have a €300 excess so unless your floor is going to cost €1000s probably not worth it.

ray.g

You want to connect the mains direct to the CH this will keep an endless supply of water feeding the leak and will also increase the size of the leak therefore increasing the sound level of the leak. Get a leak detection service to groundmic the house and even through the lagging they should be able to pick up the sound. Failing that get them to use a tracer gas on it, this should be detected the strongest on the riser nearest to the leak.

freddyuk

Water companies use a stick and their ear to listen for leaks. Maybe that gives you a cheap clue to find the location. Better than paying someone to do the same job. If the leak was doing serious damage it would manifest itself by now so pump the system up and get a stick to your ear and see what you find.

Littlehorny

Just wondering, is there such a thing available as a smoke test for this type of problem ?, we used them a few times on sewer mains which is on a larger scale granted.

airman737

freddyuk wrote: »

Water companies use a stick and their ear to listen for leaks. Maybe that gives you a cheap clue to find the location. Better than paying someone to do the same job. If the leak was doing serious damage it would manifest itself by now so pump the system up and get a stick to your ear and see what you find.

Thanks Freddy, I was wondering would the water be doing any damage underneath the house, but i guess not as there is no sign of anything ontoward. Yeah I was looking online, some people were suggesting getting a doctor's stethoscope to use to listen for the leak. I think i'll give it a try!

airman737

Littlehorny wrote: »

Just wondering, is there such a thing available as a smoke test for this type of problem ?, we used them a few times on sewer mains which is on a larger scale granted.

I know the guys that came last week use a gas composing of 95% Nitrogen and 5% helium, but it's quite expensive to use. Anyway they couldn;t use it on my system as they needed some back pressure in the pipe which I don't have! Thanks for the suggestion

airman737

ray.g wrote: »

You want to connect the mains direct to the CH this will keep an endless supply of water feeding the leak and will also increase the size of the leak therefore increasing the sound level of the leak. Get a leak detection service to groundmic the house and even through the lagging they should be able to pick up the sound. Failing that get them to use a tracer gas on it, this should be detected the strongest on the riser nearest to the leak.

Well Ray. I had the water leak detection guys down last week, they tried to pressurize the system with a hand pump thing, but nothing was happpening. They said that the gas wouldn't work as the pipe seems to have disconnected from a joint! They told me that they could connect straight to the boiler from the mains, but this was going to cost a lot of money. To be honest, they were pushing for me to do this, but I said no. At that stage I had a feeling they were looking to do a big job just to get a few extra quid.

corkgsxr

Whip off a rad and connect mains to valve. Half hour at worst

ligertigon

I would run compressed air through your heating system for a day (to change its temperature), then use a thermal image camera. your going to have to lift carpet and wooden floor in suspect areas. The broken pipe is above the dpc in the concrete screed, look carefully for efflourescence on walls and floors, especially if you have some form of heating on.

leakman

Hi, how did you get on with finding your leak?