Smell "Gas" but no gas leak

[karlpestell]

Hi All

Bit of an odd one... but here goes.

We can smell what we can only describe as gas in our living room. We have had transco out who found a small leak (upto 50ppm) on our gas fire which was repaired. The transco guy did say he was surprised we would be able to smell something that little at the time.

Anyway, we can continue to smell what we believe to be gas, the fire is 100% safe and not an issue and been verified by 3 different gas safe engineers.

The odd part now is that we only seem to smell the “gas” when the windows and patio doors are open. The gas guy we had out on Saturday was very helpful and did a digital pressure check on the meter and over a 2 min window, the pressure dropped by 0.07mb... I understand for a house of our ages, the legal limit is 4mb.

The engineer on Saturday did mention that the fact we smell it more when the doors/windows are open could be as it would appear that the flooring of the ground floor is not solid concrete but something like a suspended concrete floor as they are air vents under the damp course and the smell is coming from under the concrete. He did mention that if the gas pipe flows under here, it could be that the airflow is drawing the smell up.

I know everyone will say its a dead animal but other than start smashing up walls or digging up floors, what other options do we have to either identify if its a gas leak or in fact something rotting under the floor?

Any help appreciated

Karl

 

[Dan Robinson]

The legal limit is 4mbar only if there is no smell of gas and appliances are connected.

Turn your gas meter off for a few days and see if the smell persists.

 

[JBPHS]

Run a gas sniffer along the entire length of pipework. Starting with accessible areas of pipework and fittings.

James.

 

[karlpestell]

Thanks Dan!

We have turned off the gas before but will try again and see what happens.

I guess there must be some sort of Analysis tools to monitor exactly how much natural gas is in the air and if it is in fact heightened in the living room and that certain areas are higher than others?

 

[karlpestell]

Run a gas sniffer along the entire length of pipework. Starting with accessible areas of pipework and fittings.

James.

Problem is, we dont know exactly where the pipes run, this is a new house to us and no pipes are visible apart from on the back of the cooker into the wall.

I have tried using a sniffer that I purchased over the weekend and it seemed to pick up a heightened level of "combustible gas" in some areas but then I would re-visit the same area after 5 mins and nothing showing.

 

[footprints]

Are you sure it is not exhaust fumes form cars parked outside the window, or recycled products from a flue close to the window?

 

[Whitespirit66]

+1

Have had a couple of complaints of gas smells over the years that turned out to be exhaust from the flue. Are there any flues nearby? Gas and exhaust can smell similar.

 

[karlpestell]

+1

Have had a couple of complaints of gas smells over the years that turned out to be exhaust from the flue. Are there any flues nearby? Gas and exhaust can smell similar.

Flue is on the other side of the building and the living room is at the rear of the house so I dont think thats the case... but never say never.

I have been talking to someone about having the gas pipes detected with hydrogen to see if any leaks... at least we will know once and for all if it is a gas issue or not.

If not, we start to rip wall down lol

 

[Whitespirit66]

I would try the turning gas off for a few days suggestion first.

 

[karlpestell]

I would try the turning gas off for a few days suggestion first.

Agreed - thats what we will do to try and save some money!

 

[newbuildinstaller]

leak on your mains supply in?? Had plenty copper services replaced because they had failed

 

[karlpestell]

So after having the gas turned off for the past 36 hours, we are still smelling "gas" so can eliminate the gas leak on our internal pipes.

I'd also suggest that there is no dead animals as this smell has been ongoing for some time (circa 3 months) but gradually getting worse. I'd expect if it were a dead animal somewhere, it would have decomposed by now.

So... Now what?

My new concern is it is something under the house that's leaking but if that's the case, who would I call to help?

Any advice appreciated as at a loss now where to go next.

Karl

 

[pallen5000]

Sounds like it may be an external leak. Call National Grid out again

 

[karlpestell]

Sounds like it may be an external leak. Call National Grid out again

So transco have been out for the past 3 hours and thoroughly searched the property and also parts of the neighbours and not able to find a single trace of gas but the guy was perplexed as he could def smell it!!!

Now, the transco guy suggested talking to the council and see if they can come out and scan for other gases in case its something else. Ive called them and will get a call back tomorrow.

So... what now?

I am kind of thinking that its not an animal as been ongoing for approx 4 months and surely the animal would have decomposed by now.

Any suggestions appreciated!!!!

 

[Boilerman2]

Keep a written record of all conversations with the ESP and details of all visits supported with any worksheets that you are given - you may need these later - just keep phoning ESP to report smell of gas they HAVE to respond are any neighbours noticing any smell?