Capping off Gas Supply

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confused101

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Hi all,

I have a gas pipe which was capped off when our gas fire was removed many years ago. It's recently starting leaking a bit.. so I had a gas engineer round to seal/re-cap it somehow (don't worry the gas is completely off now so all safe!)

Anyway the gas guy told me that the pipe has been cut after capped (I guess so it could go under the floor rather than stick out), and as such he can't cap it off. He is suggesting a huge job to fix it - ie re-doing the whole gas supply to the house!

I'm going to try and get a second opinion but wanted to ask here - is there really no way this can be made safe/re-sealed somehow? If not, as I have already found the capped off end under the floor, is it possible to trace it back to the gas meter somehow and cap it at the source? Hope someone can help
 

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It looks like a concrete floor, so would need to be dug around and wrapped, usually in something like Denso tape. Best practice would be the latter and to cap at tee’d off supply.
 
Thanks Chris,
So by tee'd off supply you mean to dig and cap it where the pipe turns to head towards the gas meter? If so, any idea how deep that would be generally - an inch.. a foot??

Also - is there any way to trace this pipe back to the meter and cap it there? That way the end in the living room could just stay as is, seems like this option would have the least disturbance?
 
(I am not a plumber)

How many other appliances do you have in the house?
 
What sort of pipework do you have at the customer side of the meter? If you're lucky there'll be a manifold of some sort- far better to disconnect that under-concrete pipe completely.
If that's not an option then retubing the house is the best long-term plan.
 
Appliances - I have a boiler and gas cooker which are out of the gas meter cupboard and right, and the capped off gas fire which is out of the gas meter cupboard and straight and then left.

Pipework at the meter - I've attached a pic, hopefully this gives you some info but let me know if you need a different picture.

Generally I'd rather the work was done in the meter cupboard and cap off the supply to the gas fire there. Possible?

Any advice hugely appreciated
 

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confused101 said:
Thanks Chris,
So by tee'd off supply you mean to dig and cap it where the pipe turns to head towards the gas meter? If so, any idea how deep that would be generally - an inch.. a foot??

Also - is there any way to trace this pipe back to the meter and cap it there? That way the end in the living room could just stay as is, seems like this option would have the least disturbance?
Click to expand...
Depends on access, but having re-looked at the first photo, then it might be easier leaving as is and cap as far back where it tee’s off, or at the meter if tee’d there.

Yes you can trace it, sometimes it can be worked out, other times it’s trial and error.
 
Ooh, iron- that makes life more fun. Have a look behind the meter (left-hand side), are there any branches off the main pipe or does it just vanish under the floor?
 
Just goes straight into the floor, which I think is concrete.. That's not good is it?
 
confused101 said:
Just goes straight into the floor, which I think is concrete.. That's not good is it?
Click to expand...
Doesn't make life easy, that's for certain. If you are lucky (sketch of where meter cupboard, gas fire room and boiler/kitchen room would help) the tee may be under the meter or very close to. My concern would be that if the capped pipe has rotted under the concrete the section running to boiler and cooker will be the same age and potentially in the same condition....or was it the cap that failed?
 
What is that lump of copper behind the meter doing- is it water or something else? Like gas to the boiler?
 
oldbutnotdead said:
What is that lump of copper behind the meter doing- is it water or something else? Like gas to the boiler?
Click to expand...

One of the few posts of any merit. I noticed that pipe - is it a supply to a replaced boiler?

In almost every case the Iron pipe wil travel with the largest bore to Boiler, teeing off to other locations such as fire and cooker. So the main run will probably be in 3/4 the others 1/2”. Most old time gas men would be able to say where the likely positions are, with sight of the house or a plan. The tees will almost certainly be nowhere near the meter.

Going back to the OP: When was this pipe cut? If it was cut to fit under the floor then it would have been leaking from then? So seems a bit strange. Anyway, typically, the 1/4” will be screwed into a 1/2” x 1/4” elbow.
If this is the case then: chop the floor around where the 1/4” exits to gain sight of the elbow if it is there. Once confirmed dig the floor around and under deep and wide enough to turn the bend. Unscrew the 1/4” from the bend . Then unscrew the bend from the 1/2”. The fittings may be screwed solid, so heat the fittings if you need to. There is a danger that it can slightly deform in which case you are snookered, but that has only happened to me once AFAIR, when they were massively tight. Once removed, use a 1/2” cap to cap off.

Allof this should be done by an RGI, although you could do the excavation and investigation yourself. He will need Bahco’s or Stillsons, so the excavation needs to accommodate that tool
 
I have only just noticed pics! Are you BC sure that he could not do it simply because the square shank of the plug has been cut? It would have been cut to level it to the floor.
With the correct tool and possibly removal of timber it may be possible to grip the body and turn it
 
oldbutnotdead said:
Doesn't make life easy, that's for certain. If you are lucky (sketch of where meter cupboard, gas fire room and boiler/kitchen room would help) the tee may be under the meter or very close to. My concern would be that if the capped pipe has rotted under the concrete the section running to boiler and cooker will be the same age and potentially in the same condition....or was it the cap that failed?
Click to expand...

I think it's just the cap - if I turn the gas on I can hear and feel it coming out of there. I can do a quick sketch if it helps - but basically the cooker and boiler would be on the right of the meter, and the (capped) gas fire on the left. I'll attach another pic in a mo..
 
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