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Reducing current taken by an immersion heater

Discussion in 'Electrics UK' started by consciouspnm, 17 Feb 2012.

  1. consciouspnm

    consciouspnm

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    Does anyone know of a commercial device that will reduce the current taken by my 3Kw immersion heater down to 1 or 2 Kw.

    I know that I can get lower rated elements but my hot water cylinder has a non standard fitting so I'm stuck with it.
     
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  3. EFLImpudence

    EFLImpudence

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    No point.

    Turn down the thermostat.
     
  4. ban-all-sheds

    ban-all-sheds

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    Why would you want to do that?

    If you want water at a lower temperature, do what EFLI said, or fit a time switch.
     
  5. JohnW2

    JohnW2

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    No - and, even if there were, if it had any financial effect at all it would probably be a tendency to increase your electricity bills. As others have asked, why would you want to do that?

    Kind Regards, John
     
  6. securespark

    securespark

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    Can I join the "Why Would You Want To Do That?" camp? ;)
     
  7. ban-all-sheds

    ban-all-sheds

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    No.

    Membership is closed.
     
  8. 17thman

    17thman

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    the reason that it is pointless is the second law of thermodynamics. You cannot create or destroy energy. or even more simply E or(P)= VI. As your Immersion is a purely resistive load if you reduce the current, the energy supplied to the water is correspondingly reduced. ie, have a high current and the element is on for (x) time, reduce it by a half and the immersion heater will be on for (x) x2. What do you gain? timer or thermostat reduction is the answer
     
  9. securespark

    securespark

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    Ahhhhhh. Pleeeeeease? Pretty Please???? I'll buy you a bar of chocolate!
     
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  11. ban-all-sheds

    ban-all-sheds

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    OK, but it has to have 70% minimum cocoa solids.
     
  12. JohnW2

    JohnW2

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    Indeed - and, as I hinted, far from gaining anything, one would probably slightly lose, since heat would have been being lost from the cylinder for twice as long - so, to achieve the same water temperature, the half (power, not current) heater would have to work for a little longer than "(x) x2".

    Kind Regards, John.
     
  13. ban-all-sheds

    ban-all-sheds

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    If ever anyone is at an exhibition where someone is selling one of those devices which "save you money by reducing your supply voltage" I can recommend explaining things like that to them.

    It is great fun, especially if you can get an audience of people who had been potential buyers.

    Best to stop at the point where they tell you that if you don't stop they will call security though.
     
  14. stillp

    stillp

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    Nah, much more fun to let them actually call security!
     
  15. JohnW2

    JohnW2

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    No, don't stop at that point - but make sure you've called a journalist and given them enough time to turn up before the security folk arrive :)

    Kind Regards, John.
     
  16. 17thman

    17thman

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    I think that security need to know the truth as well
     
  17. consciouspnm

    consciouspnm

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    I want to dump the excess power from my PV array into the water but I'm not likely to have 3kw spare. I appreciate the second law of thermodynamics but as the power is free I don't care if it takes three times as long !
     
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