Gas pipe 15 mm, do i need a 22mm for boiler ?

29 Mar 2006
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Tyne and Wear
United Kingdom
iam going to install a potterton boiler which needs a 22mm gas pipe for the incoming pipe. there is 15mm installed at the minute to the old boiler.
my question is do i need to upsize it to 22mm which would mean removing cupboards etc.
the 15mm installed at the minute is about 3 meters worth (running behind cupboards)
could i simply upsize it to 22mm near to the boiler ?
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if the manufacturers instructions say 22mm then it has to be, most boilers now need the 22mm pipe to cope with demand from the appliance.
i think you may find that gas fitters and plumbers are fairly good at fitting pipes. what may seem awkward to you is all in a day's work for others.
of course, you weren't thinking of doing the gas work yourself, were you?
a qualified fitter wouldn't need to ask the question that you did
yes i am qualified. inexpericend thats why i always ask if am not sure.
(still on probation period with gas safe register)
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yes i am qualified. inexpericend thats why i always ask if am not sure.
(still on probation period with gas safe register)
And have you done the calculations? :confused: Now I'm not an RGI, but even I know that there are calculations to be done taking into account bends, appliance requirements etc. So I find it a bit worrying that you have to ask on here on an open forum to be honest.
if you want to retain your street cred as a qualified fitter, questions like that won't improve your image. the answers are either in your head, or your gas handbooks or MIs
Also to avoid giving us a bad name you should register for the CC closed part of the forum and ask those student questions there where you will be treated with a little respect and helped along.

You really should consider getting some more experience if you can't work out the answer to this question on your own, the fact that you haven't posted boiler size either casts doubts that you are competant to take on the job, if you are an RGI :cry:
dom2466, are you for real? 4 months ago you posted a question about how to plumb in a new rad. in that post you said you were an installer and were new to gas. what kind of installer needs to ask how to plumb in a rad??
now you are fretting about 3m of 22mm pipe, for gas???
RGI? you need a reality check. fast.
I was going to mention his previous posts. Pretty basic plumbing stuff not too long ago. My guess is he's in a bit of a rush; somehow got a portfolio together and got onto the ACS course. I'd recommend getting a job with someone for a couple of years and learning the basics in a real world environment before going it alone.
granted everyone has to start somewhere, but i see no signs of competence yet. RGI??
This is the perfect reason,why they should get rid of these fast course centres,letting people like this out on the unsuspecting public is wrong

Long live the proper method of an apprenticeship and being taught by someone who has many years of experience in the trade

People like these needed to be vetted alot better and it should be made cumpulsory that they have to be in employment with a proper gas registered firm for certain amount of time before they can even think about applying for their own gas safe number
Who's to say he's using his own gassafe number. Don't know the rules, but is it not possible to get in using someone else's - can't these be found easily on the gassafe site, or the benchmark at the back of anyone's boiler's MIs?

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