meter union 28mm or 22m

[julesverne]

gota boiler swap on monday that requires upgrading of the gas pipe to 28mm for 4 meters.

i already have a 28mm union which is priced in the quote.

but my question is this would it be acceptable to use the existing 22mm union and use a reducer/increaser to go to 28mm and carry on.

it doesnt seem right to me because of the restriction at the union but then you could argue the case for the store of gas in 28mm pipe

thought i would ask anyway

 

[mutley racers]

You are correct mate. Just go with the 22mm. It works fine as gas can be compressed. Totally different to water. I di it the other month and got my 1 mil drop across carcass. Also, I could not get hold of a 28mm union in time. Have only seen them on bes

 

[plumber0808]

It doesn't really matter as the 22 meter union has the same internal bore as the 28.

i like to use a 28 but have used 22 loads of times with no problem.

 

[tamz]

Gas is compressible.

 

[REDSAW]

i agree, i am waiting for this one to come out..it will be a ripper. lol

 

[mfgs]

As said, the internal diameter is the same, so may as well just use the standard one.

 

[julesverne]

Thanks guys for the replies will use the original 22mm on the meter so my next question is.

Does this mean you could put the 28mm pipework any where you see fit on the carcass practical to the application or must it be from the meter.

 

[Destroyer2813]

I'd go staight off the top of the union but saying that I had one install with low pressure so instead of replacing the whole line national grid put a 10 ft section of 63mm in the garden as a reservoir when the boilers pulled a lot at full fire

 

[julesverne]

Agree you would always endeavour to go from the meter. But you might get an install where it would be a pain so thats why i ask the second question.

 

[Destroyer2813]

In theory yes then as that bank worked on my install

 

[SafeGasInstall]

i will go from union with the first 4m in 28mm

 

[galaxy_plumbing]

depends on accessibility. if its difficult to replace section of pipe directly from the meter then fit it where you get good access.

 

[GasmanxxxR1]

Best practice is from the meter, however i did the exact thing your talking about on tuesday, i replaced 4m of 22mm with 28mm about halfway along the gas run. 28 i junior worked fine all pressures and gas rates fine

 

[jtsplumbing]

Did one a little wile back Meter on outside of a 30" stone wall, so just upsized pipe work on other side, running 2 x combi boilers ok.

 

[julesverne]

Thanks for all the replies really appreciate it. This one i am running from the meter as its easiest place to do do it . But its good to know for future jobsf