Your browser isn't supported
It looks like you're using an old web browser. To get the most out of the site and to ensure guides display correctly, we suggest upgrading your browser now. Download the latest:

Welcome to the MSE Forums

We're home to a fantastic community of MoneySavers but anyone can post. Please exercise caution & report spam, illegal, offensive or libellous posts/messages: click "report" or email forumteam@. Skimlinks & other affiliated links are turned on

Search
  • FIRST POST
    • bery_451
    • By bery_451 6th Jan 18, 8:26 PM
    • 1,160Posts
    • 31Thanks
    bery_451
    Gas meter and Gas sizes questions
    • #1
    • 6th Jan 18, 8:26 PM
    Gas meter and Gas sizes questions 6th Jan 18 at 8:26 PM
    Hi,

    Just to clarify there's only 1 gas pipe coming out from the gas meter?

    Gas cookers, boilers, fireplaces share this 1 pipe?

    Were getting a side extension done so that entails extending the gas pipe to the new boiler location.

    Also we be moving the kitchen into the new build. So gas cooker will be moving.

    Also in the new kitchen we like to install a new single eye level gas oven.

    The questions are:

    I assume the existing gas supplies to appliances will be capped off so gas pressure will be recovered back to the main 22mm gas pipe correct?

    The new cooker and new location of freestanding cooker will just simply branch off the existing 22mm gas pipe?

    Whats the max number of gas appliances and 30+ combi boiler that can run off a 22mm gas pipe without losing gas pressure?

    Whats the max distance and how many max bends can a 22mm gas pipe have without losing gas pressure?

    I asked these questions because recently I had 4 gas safe engineers come out with 2 different answers, 2 engineers saying existing 22mm gas pipe is fine and the other 2 is saying i need a bigger 28mm gas pipe
Page 1
    • Alex1983
    • By Alex1983 6th Jan 18, 8:39 PM
    • 825 Posts
    • 489 Thanks
    Alex1983
    • #2
    • 6th Jan 18, 8:39 PM
    • #2
    • 6th Jan 18, 8:39 PM
    They should of done a gas pipe size calculation, you need to know the kw size of each appliance, the length of the pipes and fittings involved.
    • ComicGeek
    • By ComicGeek 6th Jan 18, 9:30 PM
    • 285 Posts
    • 238 Thanks
    ComicGeek
    • #3
    • 6th Jan 18, 9:30 PM
    • #3
    • 6th Jan 18, 9:30 PM
    As Alex says, it needs a proper calculation not a quick look and guess. And you need to know the exact gas rates for the boiler, cooker and oven to be able to calculate it, not just that the boiler is 30+.

    Odds are high that a 28mm would be required though - unless the 2 engineers who said existing 22mm was fine have done detailed calculations that prove to the contrary I wouldn't get them back myself - they're either going to need to add more costs later on or leave you with problems.
    • bery_451
    • By bery_451 6th Jan 18, 10:23 PM
    • 1,160 Posts
    • 31 Thanks
    bery_451
    • #4
    • 6th Jan 18, 10:23 PM
    • #4
    • 6th Jan 18, 10:23 PM
    I haven't ordered the new gas cooker yet as the kitchen build is not completed yet.

    So without this how can engineer do accurate gas pipe size calculations?

    Another general question is it the matter of using all these gas appliances at the same time will reduce the gas pressure similarly like a wifi connection being shared by many the slower correct?

    Finally if the gas appliances are energy efficient then will that reduce the chances of requiring of a bigger 28mm gas pipe?
    • Alex1983
    • By Alex1983 6th Jan 18, 10:40 PM
    • 825 Posts
    • 489 Thanks
    Alex1983
    • #5
    • 6th Jan 18, 10:40 PM
    • #5
    • 6th Jan 18, 10:40 PM
    Freestanding gas cookers would normally be around 11kw obviously without know what your getting they can!!!8217;t do a exact caluation but if your going to have a single over or just a gas hob then they will be able to look at similar appliances to get a general size and do a calculation based on that. I would agree it!!!8217;s likely you will need 28mm for at least some of the gas run.

    The gas pipework needs to be big enough to allow all the appliances to work if they are all operating at the same time. If it!!!8217;s under sized and all appliances were operated then it!!!8217;s potentially dangerous.

    High efficiency appliances will still use the same amount of gas, as in a 30kw combi is still rated 30kw if it!!!8217;s standard efficiency or a high efficiency condensing boiler.
    • fezster
    • By fezster 7th Jan 18, 10:44 AM
    • 256 Posts
    • 137 Thanks
    fezster
    • #6
    • 7th Jan 18, 10:44 AM
    • #6
    • 7th Jan 18, 10:44 AM
    I asked these questions because recently I had 4 gas safe engineers come out with 2 different answers, 2 engineers saying existing 22mm gas pipe is fine and the other 2 is saying i need a bigger 28mm gas pipe
    Originally posted by bery_451
    Most likely you will need at least some 28mm for the appliances you have mentioned. The exact requirement needs to be calculated, and is based on lengths and fittings used, so ask the gas safe engineers to provide you with evidence of this.

    In order to certify the installation at the end, they will need to do a gas pressure check. If it doesn't pass, they would be on the hook for the installation, and it is potentially dangerous. They will then hit you with the added cost of upgrading the pipes. You could also discuss with them beforehand that any increased cost to upgrade the pipes later will be their responsibility.
    • a&akay
    • By a&akay 7th Jan 18, 12:03 PM
    • 523 Posts
    • 189 Thanks
    a&akay
    • #7
    • 7th Jan 18, 12:03 PM
    • #7
    • 7th Jan 18, 12:03 PM
    We built a utility extension at the far end of our house, mainly for washing but also to move the gas boiler from one end of the house to the other. The house has 6 bedrooms, 2 kitchens, and 2 receptions. The gas heating is on constantly from 6am till 10pm. We have single glazing. We have a gas oven/hob in our kitchen and a gas hob in the other one. We have gas fire in our lounge for heating top up in Summer in the evening. We have a gas tumble drier in the utility which is on pretty much all day. The 22mm pipe from the gas meter to the gas boiler is about 25m. That has by far the largest gas load. The annual pressure gas test on the boiler has never shown an issue. 2 of these have been in Winter. We've never had an issue with the gas hobs staying lit on the lowest simmer settings, which I'd say means the pressure to them is satisfactory.
    • bris
    • By bris 7th Jan 18, 12:27 PM
    • 7,674 Posts
    • 6,676 Thanks
    bris
    • #8
    • 7th Jan 18, 12:27 PM
    • #8
    • 7th Jan 18, 12:27 PM
    We built a utility extension at the far end of our house, mainly for washing but also to move the gas boiler from one end of the house to the other. The house has 6 bedrooms, 2 kitchens, and 2 receptions. The gas heating is on constantly from 6am till 10pm. We have single glazing. We have a gas oven/hob in our kitchen and a gas hob in the other one. We have gas fire in our lounge for heating top up in Summer in the evening. We have a gas tumble drier in the utility which is on pretty much all day. The 22mm pipe from the gas meter to the gas boiler is about 25m. That has by far the largest gas load. The annual pressure gas test on the boiler has never shown an issue. 2 of these have been in Winter. We've never had an issue with the gas hobs staying lit on the lowest simmer settings, which I'd say means the pressure to them is satisfactory.
    Originally posted by a&akay
    That has to be under gassed. The gas pressure must accommodate everything turned on full at once, there is a very good chance (I would bet on it) yours doesn't meet the pressures required.


    I have an app for that now (an app for everything really), saves the headache of working it all out on paper. Only needed to use it once and the when a new kitchen had a 7 burner range cooker installed. Only half those distances and not as much on the system and it need upgraded. I would get that professionally checked.
    • fezster
    • By fezster 7th Jan 18, 1:05 PM
    • 256 Posts
    • 137 Thanks
    fezster
    • #9
    • 7th Jan 18, 1:05 PM
    • #9
    • 7th Jan 18, 1:05 PM
    We built a utility extension at the far end of our house, mainly for washing but also to move the gas boiler from one end of the house to the other. The house has 6 bedrooms, 2 kitchens, and 2 receptions. The gas heating is on constantly from 6am till 10pm. We have single glazing. We have a gas oven/hob in our kitchen and a gas hob in the other one. We have gas fire in our lounge for heating top up in Summer in the evening. We have a gas tumble drier in the utility which is on pretty much all day. The 22mm pipe from the gas meter to the gas boiler is about 25m. That has by far the largest gas load. The annual pressure gas test on the boiler has never shown an issue. 2 of these have been in Winter. We've never had an issue with the gas hobs staying lit on the lowest simmer settings, which I'd say means the pressure to them is satisfactory.
    Originally posted by a&akay
    That sounds like a lot of appliances off of a 22mm gas pipe. But without knowing what the load on each appliance is, nor how the pipe is run (is it a straight pipe, does it have any bends), it's pretty irrelevant.
    • Alex1983
    • By Alex1983 7th Jan 18, 1:46 PM
    • 825 Posts
    • 489 Thanks
    Alex1983
    A&akay even if you just use basic average kw outputs for your appliances of 5kw for a tumble dryer, 2 7kw cookers, 7kw fire and a modest 18kw boiler, very modest for a 6 bed house at 25m away, with out allowing for bends etc you need at least 28mm for the majority of the gas run. I would get you system checked.
    • a&akay
    • By a&akay 7th Jan 18, 2:30 PM
    • 523 Posts
    • 189 Thanks
    a&akay
    A&akay even if you just use basic average kw outputs for your appliances of 5kw for a tumble dryer, 2 7kw cookers, 7kw fire and a modest 18kw boiler, very modest for a 6 bed house at 25m away, with out allowing for bends etc you need at least 28mm for the majority of the gas run. I would get you system checked.
    Originally posted by Alex1983
    It's checked annually on the gas service which is mandated for the boiler insurance (and has been for the past 10 years). What did't you understand about that?
    • Alex1983
    • By Alex1983 7th Jan 18, 2:43 PM
    • 825 Posts
    • 489 Thanks
    Alex1983
    Nice attitude there, 3 people who know what they!!!8217;re talking about have expressed concern.

    I could run my gas supply off a garden hose and it would work, doesn!!!8217;t mean it!!!8217;s safe or correct, best of luck with your system, I hope you don!!!8217;t have a condensing boiler.
    • southcoastrgi
    • By southcoastrgi 9th Jan 18, 11:11 PM
    • 5,354 Posts
    • 3,110 Thanks
    southcoastrgi
    It's checked annually on the gas service which is mandated for the boiler insurance (and has been for the past 10 years). What did't you understand about that?
    Originally posted by a&akay
    I hope the guy that checks has tumble dryerís on his registration because I donít know anyone that has it, plus I agree with the others there is no way you can safety feed all that off of 22mm
    I'm only here while I wait for Corrie to start.

    You get no BS from me & if I think you are wrong I WILL tell you.
Welcome to our new Forum!

Our aim is to save you money quickly and easily. We hope you like it!

Forum Team Contact us

Live Stats

2,615Posts Today

8,050Users online

Martin's Twitter
  • Ah these care free days of watching #ENG score 5 goals in the first half of a World Cup match. It reminds me of... Never.

  • Then it should be. It's not some accident. It's deliberate grappling https://t.co/UxVTuUSNio

  • Penalty yes but time someone was sent off for these wrestling moves #WorldCup

  • Follow Martin