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Discuss New boiler with option of ASHP later? in the Central Heating Forum area at

  1. Simon_djl

    Simon_djl New Member


    Hoping for a bit of advice on how to upgrade my central heating.

    I've currently got a conventional LPG boiler which I think must be about 20 years old (aprox age of house) which I'm planning on upgrading when our kitchen is done.

    Where I get confused is what to replace it with. I would prefer a combi so I don't waste heated water but I don't know if a combi will be suitable as it will need to cope heating a 4 bed house. The house has hot water taps in the kitchen, downstairs toilet, upstairs bathroom and en-suite. It will also need to provide hot water on demand for two showers located upstairs.

    Can a combi cope with this hot water demand? What if both showers are being used at the same time with the heating on?

    As part of the upgrade I was going to replace all radiators in the house with larger oversized radiators in preparation for installing an ASHP sometime in the future (we don't want to use LPG if we can use an alternative).

    Could a combi be used in conjunction with an ASHP or do they just not go together? Ideally the combi could use a small amount of LPG to provide hot water and the ASHP could take care of heating requirements.

  2. oz-plumber

    oz-plumber Plumber

    The combi won't cope with multiple demands.
    As for using an ASHP, that probably won't cope with the heating demands either.
    But you could combine the ASHP with a boiler that will heat a storage cylinder that would give you adequate hot water and heating.

    You need someone who knows what they are doing and also have a substantial budget for what you want
    • Agree Agree x 1
  3. Simon_djl

    Simon_djl New Member

    Thanks very much for your reply.

    It sounds like I should be going for a system boiler if that gives me the option of 'bolting on' an ASHP sometime in the future. At least I can get the tanks removed from the attic.

    I had a plumber come and fix a boiler breakdown recently who recommended I look into getting a combi so it's hard knowing who trust.

    If anybody can recommend a good plumber in the Congleton area, that would be great!
  4. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    Any plumber that offers a Combi option for your set up I would stay clear of
  5. Gasmk1

    Gasmk1 GSR

    my friend cover macclesfield and over your way will send his details if you need them
  6. Jimmy18

    Jimmy18 GSR

    Hybrid type of ASHP. It has Gas also. You really need to insulate your house everywhere and upsize all of your radiators. ASHP fun at a 48 degree flow temperature at best. It will have a cylinder reheat every 10 days to ward off bacteria
    Last edited: Apr 9, 2019
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