Acceptable gas pressure drop between meter and boiler?

Discussion in 'Plumbers' Talk' started by Gordon S, Apr 10, 2008.

  1. Mr Ian

    Mr Ian New Member

    Well done. Nice to see that we have rules and enforce them. Outrageous that the boss had the attitude he did.

    You can be sure WB don't need to test what the pressure loss of the pipe is - they'll know exactly what it is and have certification of it. I also can't believe they measured the pipework either - what is that going to prove??

    If in doubt, fit bigger pipework, bend it rather than put fittings in, fit street elbows, de-burr the pipework. An extra few quid in copper saves a lot of time and grief.
     
  2. Gordon S

    Gordon S Member

    UPDATE:
    Plumber came today. Entire run is now 28mm from meter to boiler with tee to gas fire near meter and tee to hob near boiler.

    The gas engineer did his tests and we still have too much of a working pressure drop! By his own admission, they are going to have to come back and do some of it in 35mm!!!
     
  3. Captain Leaky

    Captain Leaky New Member

    An expensive mistake:O!

    All that labour is not cheap and 35mm copper is hugely expensive!...you may have got yourself a bargain when it's all done.
     
  4. Water Systems

    Water Systems New Member

    UPDATE:
    Plumber came today. Entire run is now 28mm from meter
    to boiler with tee to gas fire near meter and tee to
    hob near boiler.

    The gas engineer did his tests and we still have too
    much of a working pressure drop! By his own
    admission, they are going to have to come back and do
    some of it in 35mm!!!

    Was that test with the hob on? If so he should run it back top the meter. Anyone with sense doing that would have given the boiler its own dedicated supply.

    What about the meter inlet? Does it have a 1" x 3/4" maintap? Is there a big kink in the flexible inlet?
     
  5. Northwest gas svc's

    Northwest gas svc's New Member

    I cant beleive this is still going on and 28mm pipe from meter to boiler isnt enough, as w.s. says whats the inlet like, is the meter outlet a 22mm fitting or a 28mm ??? (I have queried this previously)
     
  6. Water Systems

    Water Systems New Member

    I cant beleive this is still going on and 28mm pipe
    from meter to boiler isnt enough, as w.s. says whats
    the inlet like, is the meter outlet a 22mm fitting or
    a 28mm ??? (I have queried this previously)

    28mmm <u>all the way</u> is clearly enough - I calculated it roughly. The hob should be directly back to the meter. As you said, a 28mm meter outlet union is needed (if not fitted). What is the inlet like? Transco, when it comes to the inlet tend just walk away. A new flex inlet from BES may have made a difference, even a new governor from BES too if need be. Time is money and Transco mean many calls backs as they don't want to do anything. Cheaper to buy the bits yourself and then a satisfied customer. A 1" x 3/4" maintap can be the difference, however to replace it you need to work on live gas. Not sure if Transco would replace it for free for a 1" x1" maintap. Get all restrictions out the supply.

    I would have initially sorted out the meter and ran the hob back to the meter and then tested before installing expensive 28mm pipe.
     
  7. lemezma

    lemezma New Member

    I cant beleive this is still going on and 28mm
    pipe
    from meter to boiler isnt enough, as w.s. says
    whats
    the inlet like, is the meter outlet a 22mm fitting
    or
    a 28mm ??? (I have queried this previously)

    28mmm <u>all the way</u> is clearly enough - I
    calculated it roughly. The hob should be directly
    back to the meter. As you said, a 28mm meter outlet
    union is needed (if not fitted). What is the inlet
    like? Transco, when it comes to the inlet tend just
    walk away. A new flex inlet from BES may have made a
    difference, even a new governor from BES too if need
    be. Time is money and Transco mean many calls backs
    as they don't want to do anything. Cheaper to buy
    the bits yourself and then a satisfied customer. A
    1" x 3/4" maintap can be the difference, however to
    replace it you need to work on live gas. Not sure if
    Transco would replace it for free for a 1" x1"
    maintap. Get all restrictions out the supply.



    absolute rubbish !

    we are talking about pressure drop over pipework from meter which is measured from testpoint on meter to appliance. changing ECV ,flex and govener will change nothing the test point on meter is upstream of these even if you change these and get 23mb working pressure at meter the pipe work installed will still give the 1.5mb drop
     
  8. Water Systems

    Water Systems New Member

    we are talking about pressure drop over pipework from
    meter which is measured from testpoint on meter to
    appliance. changing ECV ,flex and govener will change
    nothing the test point on meter is upstream of these
    even if you change these and get 23mb working
    pressure at meter the pipe work installed will still
    give the 1.5mb drop

    Believe me! You get the meter right first, as it is easy enough to get right. Make sure no restrictions, and as full bore as possible. Was the working pressure at the meter taken?

    As I have said. In this case I would have concentrated on the meter, most ignore that and think you can't even take a meter out to paint behind it - you can. Then I would have taken the hob back to the meter. Then test. If still dropping too much replace a section of 28mm pipe after calculating and then test. 28mm all the way is overkill, although it is clear they were trying to supply the hob with it as well, right at the boiler. A dumb thing to do.

    The boiler should <u>always</u> have a dedicated supply pipe.
     
  9. Water Systems

    Water Systems New Member

    BTW, I was generally talking of an approach to these matters. Get the meter right first. And a dedicated boiler supply.
     
  10. Mr Ian

    Mr Ian New Member

    Of course taking into account the fact that the meter and the upstream is the property of Transco (or whoever owns it now), and is not for you to be tampering with or moving. WS is of course a law unto himself.
     
  11. Water Systems

    Water Systems New Member

    Of course taking into account the fact that the meter
    and the upstream is the property of Transco (or
    whoever owns it now), and is not for you to be
    tampering with or moving. WS is of course a law unto
    himself.

    Not another one. If a flexible meter inlet is kinked. nothing says you can't take it off and undo the kink.
     
  12. Planet Niton

    Planet Niton Member

    Any news, Gordon?
     
  13. Gordon S

    Gordon S Member

    Hello all,

    Finally sorted a while back, but as it's now over a year since the installation so I feel happy to finally reveal the installer. If you go on the link below, you won't find me on the testimonials!

    *

    At the risk of being sued for telling the truth(!), * was totally disinterested in resolving the defect when I originally contacted him. Thus I had to call CORGI in. * appeared to get the "right hump" as a result because he seemed to be happy with a 3mb pressure drop on a new installation. In the end, he finally came to the house ONLY when the CORGI inspector visited but it took a further 3 visits to enlarge the pipework to a suitable size. I am now left with an extra hole in my ceiling. Oh, yes.....and using a spirit level on the gas pipework must have been an optional extra! I've also found some gas pipework clips fitted after the event and not actually fixed to the wall. They are simply caught between the pipe and the wall.....spacers (?) I suppose.

    Frankly it has all been a *. Even this morning I've had to waste time writing a letter to Worcester Bosch confirming that the fault with the gas installation has been rectified.

    Can anyone recommend a good plumber in the Wimborne (BH21) area to replace 3 radiators?

    Thanks for everyones help.

    Regards

    Gordon

    [Edited by: admin]
     
  14. HOTDOG ø

    HOTDOG ø Active Member

    P L Matthews Plumbing & Heating Ltd

    79 Springdale Road,
    Broadstone,
    BH18 9BN

    Tel: 01202 602245
    Mob: 07768 534134

    Excellent plumber who will probably be busy!

    Or

    S L Jewell Plumbing & Heating Ltd

    5 LOWER BLANDFORD ROAD
    BROADSTONE
    DORSET
    BH188NR

    01202 640000

    Both excellent.
     
  15. mad.max

    mad.max New Member

    Any questions?



    Am I missing something? The CORGI inspector insisted on a max 1 mb drop from meter to test point, as you would expect. He won't take into account the (excessive) internal pressure drop. At some point he must have realized that this is impossible, taking into account the 1.5mb inherent loss, so he changes the rule to a maximum of 1.5mb. He is now effectively saying that NO pressure drop is allowed over the actual carcass. Slightly harsh, methinks
     
  16. Captain Leaky

    Captain Leaky New Member

    Maybe but once a fat lazy CORGI inspector actually gets of his pimpled bum to visit a job he's going to go by the letter isn't he?
     
  17. Gordon S

    Gordon S Member

    I don't really understand the question (as such), but I do know that the installer had to make 3 visits in total to keep upping the size of the pipe in certain sections to get to a max loss of 1mb. The CORGI inspector didn't appear to be fat or lazy(!), but was very much "by the book" despite being on first name terms with Mr. Rice.
     
  18. Captain Leaky

    Captain Leaky New Member

    Just being rude ;)

    By the way the plumbers recommend above by HD are very good, I know them both. I would offer to do the rads as I live near you but I'm almost fully booked until next April.
     
  19. Gordon S

    Gordon S Member

    Thanks Captain Leaky, but I am probably considered a nightmare client now! I've got a fella coming round tomorrow to remove the rads. The new rads don't need fitting for 2-3 months whilst we do renovation work.
     
  20. Pongping

    Pongping New Member

    WB very soon are only going to be looking for an inlet pressure of 17mbar. Was speaking to one of their training engineers.
     

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