very slow gas leak

[Ariel]

I have a very slow gas leak in my house that I simply can't find.

The gas is leaking at a rate of 1.7 cubic feet per day (0.071 cubic feet per hour) as measured by the meter.

I don't smell gas anywhere, and I have looked at (sniffed actually) every joint I could reach, and nothing.

My question is how sensitive of a detector would I need in order to find this? I have seen detectors with ppm sensitivity ranging from 50 to

2000. Obviously price goes accordingly, how sensitive of a detector do I need?

And realistically speaking, how bad of a leak is it? I know that any leak at all sounds scary, but a leak so slow that you can't smell it is not a fire hazard as far as I know, but it does waste gas.

-Ariel

[Pilbs]

What gas appliances do you have in the house?

[Andy Hill]

Why worry about finding it yourself? Call the gas company, and tell 'em "my gas appliances are all off, but the meter is still running". That should get some folks who know what they're doing out in a jiffy -- the gas company just hates the publicity when a house blows up.

[Ariel]

I have a water heater, stove (range), and furnace, but the valves to all of them were off, plus the valves internal to the units were off as well (just in case) when I tested this.

-Ariel

[Andrew Gabriel]

Have you tried closing all the appliance isolator valves to see if one of them stops the leak?

A leak inside a room sealed appliance would not generate a gas smell inside the house, but outside at the flue terminal. Likewise, if the meter is outside, check for leaks in the pipework before it enters the house.

This is very unlikely to generate an explosive mixture. It would have to be leaking into a small rather well sealed cavity in the building structure at your leak rate (assuming meter is accurate at such a low flow rate) to form an explosive gas/air mixture.

Have you tried gas leak detector spray, e.g. a can of LD-90 which should be relatively cheap? This will generate a small clump of white foam at a leak after some minutes which might be easier to see than smell.

You could call Transco. If they can find and fix the leak in 30 minutes, I think it's free, but otherwise they'll disconnect you after verifying it's not their meter or couplings at fault.

[zaax]

A friend of mine did that. They came round and agreed he had a leak and promptly cut him off. He had to get a corgi registered person to find the leak and fix it. The leak was in a concrete floor. The acid in the concrete had attacked the copper pipe.

[PhilÃÂÂÂ]

Be careful, when they prove it is not the meter or connecting pipes, and you are still leaking, they will cut you off.

[Speedy Jim]

Is any part of the pipe run from the meter to house buried? Leaks are more common there.

In the US, a call to the gas utility will produce a tech armed with the latest in "sniffer' equipment in a surprisingly short time.

Testo 316-1

A bit pricey for one-off job.

Jim

[Dave Liquorice]

Any pilot lights? Though I'd expect one to use more gas than 1.7 cuft/day.

[Andy Hill]

Damn, y'all got some hard-assed utility companies over on the east side of the pond. Both time I had leaks, the gas company had one of their guys do a sniffer check around the house until the leak was found. Had to shut down the valve to the appliance (well, duh!), but they didn't red-tag the whole house.

[andrewpreece]

Can you get to look at the supply pipes? If you have a suspended wooden floor they'll likely be routed under that. Get down there with a light and a can of 'snoop' ( or I suppose squeezy and water, but remember to wipe it off when you've finshed ), and look for leaks at all the joints you came across.

Andy

[Cicero]

=============== Just a remote possibility.................

Have you got a dripping hot tap somewhere on the water heater circuit? It's possible that the water diaphragm has become weakened and is allowing the gas valve to operate at a lower pressure than it should. I don't even know if this is possible but it's worth a quick check around even though you said the valves were turned off, just in case you missed something.

Cic.

[Andrew Gabriel]

In the UK, the gas transporter (Transco) will try and find the leak and disconnect the affected appliance. They will only disconnect the whole house if they can't find the leak, or can't fix it by disconnecting an appliance. They are not responsible for fixing the leak (unless it's in their meter or other associated supply pipework) -- their service is free and is only to make the installation safe. It seems that as a free goodwill guesture, they will spend up to 30 minutes fixing a leak in your pipework if that's all that's required to solve the problem. Otherwise, you will have to employ a gas fitter to repair the leak and reconnect.

[Fergie]

Same happened to me a few years ago, neighbours smelt gas, called out BG and no leak found in their house. I was away for a few days luckily they could get access to a meter detected a drop and cut me off. If they hadn't the first thing I might have done was walk into the house and automatically turn on the lights.....BOOM

BG came round and found no leak so they reconnected me. Then a few weeks later brief whiffs were smelt but yet again BG found nothing. The fault was eventually traced to a nail on a carpet gripper rod that had just pierced a gas pipe running under the floor causing the leak to come and go with temperature change. When the vinyl floor tiles were lifted the concrete was saturated with gas.

In the days before sds drills I had to chisel by hand the rock hard concrete out from round the pipe - it took about 5 hours.

[Owain]

Meters aren't for measuring gas leaks. Get your pipework and appliances pressure tested with a manometer and that will tell you if you have a leak.

Does your boiler have a pilot light?

Owain

[Fergie]

Could you explain for the thickies just how this is possible?

[Ed Sirett]

If you are competent to perform the _correct_ procedure to detect for a gas leak as outlined in the FAQ, then do so. Otherwise call Trancso 0800

111 999. They will have someone out promptly and they will perfrom the test for you.

If you establish there is a leak then try with some/all of the appliances turned off on their service isolators. If the leak is in the pipework it _must_ be dealt with.

Also note that one turn of the meter dial is one cubic ft. The 0.071 refers to the internal workings of the meter which can be ignored for the purpose of this discussion.

[Dave Liquorice]

A "room sealed appliance" is just that, it is sealed from the room. Nothing on the inside can get into the room, air comes in and exhaust goes out through the balanced flue. SO the only place you'd smell a gas leak in the appliance is outside at the flue.

[tarquinlinbin]

Its not actually the gas companies fault if his house blows up unless they are negligent.. The OP is already in breach of the Gas safety installtion and use regs by using an installation which he believes or suspects is dangerous. A simple call to 0800111999 would confirm whether or not leakage is occuring and that visit would cost him nothing. For all he knows the leakage might be on the meter installation so again cost= nothing. But no,for the sake of spending a few quid,he is happy to risk the welfare of himself,his family and his neihbours. Meanwhile he probaly thinks nothing of spending big bucks on cars,electronic goods and foreign holidays. It really is beyond belief.

joe Remove antispam and add 670 after bra to email

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[tarquinlinbin]

Indeed Andrew,what could be fairer? A man comes to your house and gives you half and hours worth of his expertise free of charge AND maybe preserves the safety and property of the customer and his neighbours. Who else comes round and works for free? Remove antispam and add 670 after bra to email

Be a good Global citizen-CONSUME>CONFORM>OBEY

Circumcision- A crime and an abuse.