Radiators in series.

Discussion in 'Plumbing and Central Heating' started by conny, 1 Jan 2009.

  1. conny

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    We had a conservatory built last year and now plan on installing 2 radiators. As the conservatory is off the living room can we run the 2 new rads in series with the living room one?
    i.e. Into the living room radiator through the TRV, out of this rad to the first then second radiator in the conservatory and then the return pipework connected to the original return in the living room. I realise using this method means I couldn't switch off individual radiators without it turning off the others in the circuit but am prepared to accept this.
    What type of valve/lockshield would be best suited for each radiator in this situation?

    Any help would be much appreciated.
     
  2. mogget

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    If the radiators are connected in series then the same volume of water will have to pass through all, losing heat as it goes, so you could have a maximum of one functional lockshield and one functional TRV for the whole setup.

    This seems a very hacky way of doing things to me, and I suspect that what you suggest would be against the building regulations.

    What's wrong with tee-ing into the flow and return to the living room radiator?

    Is this a microbore system?
     
  3. PerryOne

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    To get this to work, you need to consider what you are trying to accomplish.
    First a conservatory can soak up a lot of heat.
    Have you worked out an expected heat requirement?
    Do you intend to use it all year round?
    Today it has been minus 7.3 C.
    Have you room for the size of radiators required to cope with the heat loss?
    Can the pipes to your existing radiator carry enough heat to heat the room it serves at present and the heat required by the conservatory radiators? Has your boiler the spare capacity?
    I have found that a all year round conservatory is best heated underfloor, that is the only way to get all over comfort.
    And then, have you considered the running cost?
     
  4. conny

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    Mogget & Perryone,
    thanks for your quick replies.

    First off, the pipework suppying all the rads in the house is 10mm teed off a 22mm from the boiler. We haven't considered yet the size of the new rads as we are trying to find the best method first so are certainly open to any other suggestions you may have. I have a book somewhere that tells you how to calculate the Btu's needed for a room taking account of the size and construction so will dig it out and refresh my memory.
    The boiler is a Jaguar 23kW wall hung boiler Cat II made for the Plumb Centre by Hepworth Heating Division. It currentlt feeds 7 radiators, 2 off 39"W x 20"H, 1 off 45"W x 19"H, and 1 off 19"W x 24"H. These are doubles. 1 off 39"W x 18"H, 1 off 50"W x18"H, and finally 1 off 32"W x 29"H. These last 3 are singles. The conservatory is 12' x 9'-6" with one full brick/thermalite cavity wall with rockwool insulation and 3 dwarf walls of the same construction. The base is concrete with an overlay of 18 high density chipboard plus 2mm foam and engineered board planking finish with a 6'x6'-6" opening to the living room.
    Hope all this information helps and am greatful for your input so far.

    PS the windows are K glass with a 19mm airgap uPVC frame.
     
  5. swbjackson

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    The 10mm pipe is very unlikely to be able to provide enough flow to heat 3 radiators whether piped in series or parallel. You need to pick up from the 22mm pipework.

    Mike
     
  6. conny

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    Thanks Mike,
    suspected that may be the case but as the bedroom floor is laminated, (thats the room where the boiler is located), didn't fancy ripping it up but needs must if the devil drives as they say. Do you think the boiler has the capcity for another 2 radiators?
    Thanks.
     
  7. swbjackson

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    The boiler should be able to run another two radiators but I'm not a huge fan of Jaguar boilers. I only ever fitted one and took it out 18 months later and fitted a Worcester.

    Mike
     
  8. PerryOne

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    Lets try to progress.
    Its been cold recently, agreed?
    Have all your rooms been as comfortable as required?
    What setting is on the boiler?
    Gives a rough idea what spare heat you may have.
    A 10mm pipe in a pressurised system can deliver 1.609kwh.
    A 22mm 12 kwh
    The radiator in the room uses what?
    What does the whole house use on a cold day/night?
     
  9. conny

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    The boiler is set at 70 at the moment because its so cold though normally it is at 60-65.
    With the exception of the living room because it opens into the conservatory all the rooms have been very comfortable, the front dining room actually gets too hot, (39"W x 20"H Double, room size is 14'x10'x8'H), so we could easily turn this one down and still feel comfy. Also usually we don't have the bedroom one on at all as it gets too warm when we go to bed. (50" x 18" single, room size is 14'x14'x8')

    I'm not sure what you mean by these next two questions.
    Do you mean how much heat in Btu's does it use, if so how do I figure that out.

    Thanks for your help so far.
     
  10. bengasman

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    boiler can pull 2 more rads
    10mm pipe is unlikely to do the job
    if memory serves me right, it does not matter as a conservatory needs to have separate controls anyway to comply with building regs so you can't link the new ones directly to another rad anyway
     
  11. conny

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    Bengasman,
    thanks for the reply. So realistically I have no alternative other than feed off the 22mm? Just have to work out what size radiators I need now. :LOL:

    Thank you gentlemen for all your help.
     
  12. bengasman

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    and don't forget the timer, roomstat and zonevalve
     

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