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What Size Boiler?

Discussion in 'Plumbing and Central Heating' started by garash, 24 Aug 2020.

  1. garash

    garash

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    I want to have a Combi installed. The property is a one bedroom 4 radiator Bungalow. What would the minimum output size requirement be for this size property?
     
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  3. oldbutnotdead

    oldbutnotdead

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    You need to do some heat loss calcs- you'll need to know whether walls are solid, how much loft insulation there is, any underfloor insulation, dg windows...once you've done those you'll know how much energy is required.
    Before you put a combi in, make sure cold water flow/pressure are up to the job.
     
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  4. bernardgreen

    bernardgreen

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    As mentioned check your water supply is suitable before committing to a combi

    The heat output rating you need is determined by the hot water requirement ( flow and temperature ) that you need

    Then for room heating the boiler has to modulate ( reduce ) it's heat output to match the much lower heating requirement.

    There is a minimum heat output that the boiler can modulate down to. After that the boiler has to turn it's flame ON and OFF in cycles to provide the low room heating requirement
     
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  5. denso13

    denso13

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    Better getting someone local to look at it and advise you on the options. You'll get a lot of guessing/scaremongering from some on here without actually knowing your requirements.
     
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  7. ianmcd

    ianmcd

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    Any Combi will be enough for your heating requirements, your only concern is the Hot water usage
     
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  8. bernardgreen

    bernardgreen

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    Agreed, but do not forget that if the boiler is too large and cannot modulate down to match the heating load then it will have go into cycle mode ( ON and OFF ) and this will increase wear and tear on the boiler.
     
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  9. garash

    garash

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    Thank you for your reply. I appreciate all the responses I obviously do not want to lay out for a Boiler that would serve a 3 bed 7 rad house. Perhaps I should have said that in the beginning!
     
  10. ianmcd

    ianmcd

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    we still need toknow your HW requirements
     
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  11. DIYnot Local

    DIYnot Local

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