trac pipe how much gas can it carry

[sheff paul]

as the title says,doing a bit of new build subbing on a new apartment block,they have got me gas testing and commissioning on Monday.The problem I can see is that the gas meter is in a floor mounted box ,next to the garage,the top floor apartment is 4 floors high including the garage level,they have got 22 mm of the meter,4 elbows,then is disappears into the building in trac pipe,the boiler is a 15 kw system boiler,and a hotplate,situated about 35 metres away,i think it may struggle to achieve a 1mbar drop across the system unless trac pipe is wonder stuff with zero resistance,just going to flick on there website now

 

[AWheating]

its not far off the same as other materials. If you checkout the trac pipe website, and the instructions they give you the info for pipe sizing. From what you have discribed the pipework is to small. Doing a working pressure at the meter and at the test point where it enters the flat at the aecv. You will know for sure then. If you test at the boiler you will get the "the MI say its ok" statement from your gaffa.

i did some 4 storey flats years back and we used 28 on the ground and first floor, and 32 on the other floor if memory serves me.

 

[sheff paul]

its not far off the same as other materials. If you checkout the trac pipe website, and the instructions they give you the info for pipe sizing. From what you have discribed the pipework is to small. Doing a working pressure at the meter and at the test point where it enters the flat at the aecv. You will know for sure then. If you test at the boiler you will get the "the MI say its ok" statement from your gaffa.

i did some 4 storey flats years back and we used 28 on the ground and first floor, and 32 on the other floor if memory serves me.

too right AW amazing how many plumbers ive come across don't test the meter for working pressure,just read the boiler spiel and say ''its ok over 15 mb'',even though they have a healthy 21mb at the meter

 

[AWheating]

that 15mb will be having min working pressure of 19mb, a 1mb drop across the pipework giving 18mb at the boiler inlet, then allowing the manufacturers pipework drop inside the boiler which is normally 1-2.5mb depending on the boiler.

have they fitted aecv's at the point of entry or just outside the front door? ive seen jobs where they have run the gas pipe from external meter to boiler cupboard in the middle of the flat with the aecv under the boiler. So when you turn it off it does not isolate any of the actual pipework in the screed just the meter under the boiler. It had to all be alterd.

 

[IDCHAPPY]

I'd always rather have a gas pipe too big than too small, as you say it's a long run of 22mm...

 

[Ermintrude]

Flats always the same. Builders too. Bet track pipe was dragged in by labourers and in a right mess!

 

[sheff paul]

that 15mb will be having min working pressure of 19mb, a 1mb drop across the pipework giving 18mb at the boiler inlet, then allowing the manufacturers pipework drop inside the boiler which is normally 1-2.5mb depending on the boiler.

have they fitted aecv's at the point of entry or just outside the front door? ive seen jobs where they have run the gas pipe from external meter to boiler cupboard in the middle of the flat with the aecv under the boiler. So when you turn it off it does not isolate any of the actual pipework in the screed just the meter under the boiler. It had to all be alterd.

funny you say that,the aecv is under the sink,a long way from where the pipe enters the building

 

[AWheating]

Then I don't think the pipework meet the regs. The Acev should isolate the entire pipework in the flat. What happens when they smell gas, turn off the Aecv assuming they have isolated it and are safe? While the pipe work before the Aecv inside the flat is still leaking.

 

[mfgs]

Then I don't think the pipework meet the regs. The Acev should isolate the entire pipework in the flat. What happens when they smell gas, turn off the Aecv assuming they have isolated it and are safe? While the pipe work before the Aecv inside the flat is still leaking.

You are right, but it can be a real nightmare trying to get one in an accessible place on point of entry to the building. I think the regs state as close as is practically possible or something. Its not always possible for it to isolate every joint or fitting inside the flat.

 

[Ermintrude]

We have seen them at the front door behind flaps.... Only issue is they at 10' from floor and label had been painted over.

 

[IDCHAPPY]

Flats should always be designed so the gas meter is in a cupboard right by the front door, then if Trac pipe is used it comes up in there with an AECV to isolated everything inside the flat anything else is shyte.

 

[sheff paul]

Flats should always be designed so the gas meter is in a cupboard right by the front door, then if Trac pipe is used it comes up in there with an AECV to isolated everything inside the flat anything else is shyte.

your right social housing tends to have steel barrel externally with AECV on point on entry,developers tend to want neat finishes no utility cupboards,but when the flat is sold after the 1st service the buyer gets a shock,and when he/she wants to sell it on,pre buyer inspection can cause problems

 

[AWheating]

Flats should always be designed so the gas meter is in a cupboard right by the front door, then if Trac pipe is used it comes up in there with an AECV to isolated everything inside the flat anything else is shyte.

In high rise yes. But in maisonette/ low level flats they will not put gas meters inside unless it's a ground floor plant room. It's a big cost.

 

[AWheating]

Aecv should be either outside by the door in a purpose made cupboard ( fire rated and ventilated) or at the point of entry into the flat. If the builder does not want a boxing in the lounge then you need to run the external pipework around the outside to another location.

Really long pipe run may cross over into commercial testing volumes. Especially with out the correctly positioned Aecv.

 

[GasmanxxxR1]

As AW has said remember to check your iv volumes. However ive heard that if there is a aecv with a test nipple you can test the pipe in sections. Or shut off the aecv and use the boiler test nipple for TT

 

[AWheating]

not a great advantage if the aecv is 1 meter from the boiler instead on entry point.