1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Is there a maximum 15 mm pipe length from the 22 mm ring?

Discussion in 'Plumbing and Central Heating' started by llChopperll, 29 Jan 2017.

  1. llChopperll

    llChopperll

    Joined:
    17 Feb 2015
    Messages:
    5
    Thanks Received:
    0
    Location:
    Staffordshire
    Country:
    United Kingdom
    Hi,

    I'm wanting to add 2*1783 watt (6084 BTU) radiators to my existing central heating system. Assuming that the boiler is large enough to accommodate the addition is there a maximum length of 15 mm pipe that can be run from the 22mm ring?

    I am planning two individual flow and returns as I doubt that two radiators of this size would work properly off one (correct me if I'm wrong).
    The 22 mm ring is on the first floor and the two 15mm flow and return running to the radiators on the ground floor (approximately 9m horizontal and 2.4 vertical for each flow and each return).
    Would there be enough pressure in the system or would I have to extend the 22 mm ring?

    Thanks for any constructive input

    IIChopperII
     
  2. stem

    stem

    Joined:
    20 Jul 2005
    Messages:
    5,583
    Thanks Received:
    1,130
    Location:
    Nottinghamshire
    Country:
    United Kingdom
    If you have a 22mm pipe run as a "ring" then this is what is known as a 'one pipe system' and the ring should be extended so that it runs underneath the radiators, so that they sit atop it like this.

    [​IMG]

    The 'T' going directly up from the ring to the radiator will be in 15mm, but it will be very short.
     
  3. muggles

    muggles

    Joined:
    28 Oct 2005
    Messages:
    10,960
    Thanks Received:
    2,141
    Location:
    Oxfordshire
    Country:
    United Kingdom
    You've not given us any information about the spec of your central heating pump so I'm afraid it's a little difficult to advise whether it's capable of pumping that far or not
     
  4. Agile

    Agile

    Joined:
    26 Jun 2004
    Messages:
    63,560
    Thanks Received:
    4,511
    Location:
    London
    Country:
    United Kingdom
    Quite apart from telling us if it is a condensing boiler or not!

    Apparently some heating aspects are not quite so simple!

    Tony
     
  5. 45yearsagasman

    45yearsagasman

    Joined:
    14 Mar 2010
    Messages:
    6,060
    Thanks Received:
    1,074
    Location:
    Norfolk
    Country:
    United Kingdom
    Tell us more about your system and its age.
     
  6. slippyr4

    slippyr4

    Joined:
    12 Jul 2005
    Messages:
    994
    Thanks Received:
    30
    Location:
    Bedfordshire
    Country:
    United Kingdom
    If he has a one pipe system, it shouldn't be extended, it should be replaced!!!
     
  7. Agile

    Agile

    Joined:
    26 Jun 2004
    Messages:
    63,560
    Thanks Received:
    4,511
    Location:
    London
    Country:
    United Kingdom
    I don't see any evidence of it being likely to be a one pipe!
     
  8. slippyr4

    slippyr4

    Joined:
    12 Jul 2005
    Messages:
    994
    Thanks Received:
    30
    Location:
    Bedfordshire
    Country:
    United Kingdom
    Me either but it's what stem said,above. Horrible things.
     
  9. stem

    stem

    Joined:
    20 Jul 2005
    Messages:
    5,583
    Thanks Received:
    1,130
    Location:
    Nottinghamshire
    Country:
    United Kingdom
    It's quite simple the OP described it as:

    A one pipe system is a 'ring' of pipe that flows from the boiler and back to it in a loop as per the diagram I posted. Other systems have separate pipes for flow and return, they are not configured as a ring.

    It maybe that the OP has used the wrong terminology, but his post does state that it is a ring.
     
  10. Agile

    Agile

    Joined:
    26 Jun 2004
    Messages:
    63,560
    Thanks Received:
    4,511
    Location:
    London
    Country:
    United Kingdom
    And he has twice mentioned a flow and return!

    Unlikely he is using the correct terms but my bets would be a conventional system!
     
  11. BigSnoopy01

    BigSnoopy01

    Joined:
    27 Sep 2012
    Messages:
    329
    Thanks Received:
    38
    Location:
    West Midlands
    Country:
    United Kingdom
    one pipes are fine on modern boilers although not ideal. no need to rip the lot out. more important to get the right vavles and balance system.
     
    • Thanks Thanks x 1
  12. stem

    stem

    Joined:
    20 Jul 2005
    Messages:
    5,583
    Thanks Received:
    1,130
    Location:
    Nottinghamshire
    Country:
    United Kingdom
    The OP's question is "Is there a maximum 15 mm pipe length from the 22 mm ring?"

    He does mention flow and returns, but the post states that he wants to add the "flow and returns" to the "ring". He doesn't say that they are there already. Maybe he has used the wrong term, but 'ring' is hardly a technical word, the OP's question is "Is there a maximum 15 mm pipe length from the 22 mm ring?" Perhaps the OP will confirm what he has, then we can all stop guessing.
     
    Last edited: 30 Jan 2017
  13. llChopperll

    llChopperll

    Joined:
    17 Feb 2015
    Messages:
    5
    Thanks Received:
    0
    Location:
    Staffordshire
    Country:
    United Kingdom
    Thanks for the reply's and sorry for the wrong use of terminology.

    The system is a conventional one with a 22mm flow and return with the 15mm flow and returns 'T'd off this. I've attached a diagram of current and proposed set up.
    I think the boiler is a Feroli domicompact F30 B (making it a condensing boiler Agile), and a 30kw output.
    muggles I'm unsure of the pump spec, but have attached what I think is a relevant page from the manual.
    FYI There is a 12ltr external expansion tank in the set up.

    Radiator Extension.pdf
    3540B282.pdf

    Hope this clears up any ambiguity

    IIChopperII
     

    Attached Files:

    • Like Like x 1
  14. Agile

    Agile

    Joined:
    26 Jun 2004
    Messages:
    63,560
    Thanks Received:
    4,511
    Location:
    London
    Country:
    United Kingdom
    The usual rule of thumb for non condensing boilers was that you could take about 3 kW from 15 mm pipes up to about 3-4 m from the 22 mm.

    With a condensing boiler set to a differential of nearly 20C then you could almost double the distance or power.

    Tony
     
    • Thanks Thanks x 1
  15. Steelmasons

    Steelmasons

    Joined:
    10 Oct 2011
    Messages:
    16,405
    Thanks Received:
    3,969
    Country:
    United Kingdom
    15mm tube will carry a 6kw load @ 10c dt. (0.14 x 4.2 x 10c = 5.8 kW)
    15 mm tube @ 20 dt (0.14 x 4.2 x 20c = 11.6 kW)
    Tony , had you of recieved the correct training then you wouldn't be making these school boy errors.
     
    • Thanks Thanks x 2
    • Like Like x 2
Loading...

Share This Page