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Reverse acting thermostat

Discussion in 'Plumbing and Central Heating' started by Geoff Forrester, 19 Mar 2018.

  1. Geoff Forrester

    Geoff Forrester

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    We have a multi fuel stove which does the central heating. Which at night if we are not careful will overheat. I wish to put a reverse acting thermostat near the stove to prevent the water boiling over. We have a thermostat which controls the central heating pump. The thermostat is turned down at night. Could I put a live wire to a reverse acting thermostat and then a wire to the pump. Then when the reverse kicks in it will start the pump to stop the water boiling. Will this be safe
     
  2. Dan Robinson

    Dan Robinson

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    No solid fuel system should rely on electricity to be safe.
     
  3. Geoff Forrester

    Geoff Forrester

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    Sorry but you have to have electricity to run the central heating pump.
     
  4. Dan Robinson

    Dan Robinson

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    No schit?
     
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  5. muggles

    muggles

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    Yes you do need electricity to run the pump, but Dan is quite correct in what he says - a properly installed and set up solid fuel heating system MUST be able to dissipate the heat it generates in the event of a powercut...IE it shouldn't be able to overheat when you have no power. Relying on electrical systems to dissipate heat isn't considered safe and does not comply with regulations
     
  6. Geoff Forrester

    Geoff Forrester

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    When you get a power cut you have to dampen the stove down and life the lids to let the heat out and there is on other way of doing it unless you have a generator. I don't think you have had many power cuts and I don't know which regulations you are talking about There is none like that in the UK
     
  7. Dan Robinson

    Dan Robinson

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    Prat.
     
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  8. muggles

    muggles

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    I'm fully HETAS qualified for both dry and wet stove installations. I do know what I'm talking about. Suit yourself though, if you don't want to take advice from professionals then off you trot, I'm sure someone somewhere will be happy to tell you what you want to hear
     
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  9. FiremanT

    FiremanT

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    Wheres Bernie when you need him? ;)
     
    Last edited: 20 Mar 2018
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  10. big-all

    big-all

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    part j building regs
    https://www.gov.uk/government/publi...-and-fuel-storage-systems-approved-document-j
     
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  11. baldykev

    baldykev

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    Sorry but you DO need a thermal dump in case of power cuts or pump failure. I looked into this when I installed my log burner.
     
  12. AdvanceHelpline

    AdvanceHelpline

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    There's no reason why you can't fit a pump, but these chaps are correct - you will also need a mechanical safeguard like a thermal safety valve and discharge/quench arrangement that works without power.
     
  13. bernardgreen

    bernardgreen

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    A thermal dump has been mentioned, that uses gravity to create circulation from the boiler to a thermal dump which should be large enough to dissipate the heat from the log burner with a full loading of logs. ( worse case ) For a small log burner this could be a large radiator. For a large burner a tank of sacrificial cold water may be necessary to remove heat from the heat dump. Sacrifical as when heated it is dumped into the drains. The control of this must NOT require an elecrical supply

    I was needed elsewhere, sorry. Though you seem to have the matter in hand. :mrgreen:
     
  14. Nozzle

    Nozzle

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    Natural Circulation. Heat source down low, heat sink up high, fully primed system, minimise the friction in flow and return.

    Job done.

    There's nothing stopping you have a pump IN ADDITION, but that's very different from having to rely on it for safety.

    Nozzle
     
    Last edited: 21 Mar 2018
  15. bernardgreen

    bernardgreen

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    The problem with that is that the pump at standstill ( no power ) creates friction that reduces natural ( thermal ) circulation.
     
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