Q please

Discussion in 'Fridges & Ovens' started by Figaro, Jul 3, 2018.

  1. Figaro

    Figaro Funster

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    When on gas, does having vent fans running to disperse heat make it more or less effective at cooling ?
     
  2. Lenny HB

    Lenny HB Funster

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    Vastly better, useless in hot weather without the fans running.
     
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  3. peterc10

    peterc10 Funster

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    It depends on where the fans are. If they are at the top of the cavity behind the fridge and blowing air out then it makes the fridge and freezer work much better
     
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  4. DP_JAY

    DP_JAY Funster Life Member

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    Yes, but ONLY in hot weather. Accidently had ours on once in April & the freezer defrosted.
     
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  5. Lenny HB

    Lenny HB Funster

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    Doesn't happen if you fit a temperature controller.
     
  6. DP_JAY

    DP_JAY Funster Life Member

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    Obviously
     
  7. Figaro

    Figaro Funster

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    They're at the top vent blowing out.
    My fridge is playing up on gas and the only way i know it's working is to feel the flue vent to see if it's hot. But with fans blowing I can barely be felt.
    Anyway I've rigged up a remote digital thermometer to put in the freezer and it seems to be ok.
    33c here in Wertheim am Mein !
     
  8. pappajohn

    pappajohn Funster Life Member

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    Let's see if I got this right......

    In cooler climes the burner gases convect quite rapidly (cooler ambient air, warm exhaust) drawing heat from the fridge coolant.

    In much warmer climes the ambient air temperature and exhaust gas temperature are much closer matched so the convection is much slower drawing less heat from the fridge coolant.
    Having fans running draws air faster through the cavity area and faster moving air is always cooler than static air (think standing in front of a fan on a hot day) so the exhaust gas rises faster and draws more heat from the fridge coolant.

    Physics dear boy, physics.
     
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  9. Figaro

    Figaro Funster

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    Thankyou sir, my thinking exactly, shall I clean the blackboard now ?

    @pappajohn
     
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  10. matamoros

    matamoros Funster

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    Not sure about the moving air being colder than static air, the only reason the air from a fan feels cooler is because of evaporation from the skin and replacing air warmed by our body with cooler ambient air, unless of coursevthe ambient air temp is greater than 39.8°C.

    A draught created by a fridge fan moves heated air from the fins of the coolant radiator and replaces it with cooler ambient air more efficiently than convection currents, think car radiator.

    At least that's my attempt at the physics.....but I did fail A level physics:)
     
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  11. pappajohn

    pappajohn Funster Life Member

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    OK, so using that basis you don't actually need gas as the air will remove the heat by evaporation. :whistle::D

    When I was at school A level was something you used to check if something was sloping.
     
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  12. matamoros

    matamoros Funster

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    Burning the gas causes the refrigerant to evaporate in the sealed system and then condense in another part, taking heat away from the air inside the refrigerator, I do not understand that process fully but I do understand that the heat withdrawn from the refrigerator has to go somewhere and that somewhere is the finned radiator on the back.

    The heat is exchanged from that radiator to the surrounding air which will rise by convection to the top vent and be replaced by cooler air through the bottom vent, in warm weather this process is aided by increasing the air flow over the fins with the fans.

    The gas is burnt to provide an energy source to drive the system, and is exhausted separately from the coolant air.
     
  13. pappajohn

    pappajohn Funster Life Member

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    Well I did say........

     
  14. Richard and Ann

    Richard and Ann Funster

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  15. JJ

    JJ Funster

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    I believe it is all down to latent heat folks... latent heat.

    (I left school before 6th form though.)


    JJ :cool:
     
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  16. Geo

    Geo Trader - Funster

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    Physics, "Who the hell is Physics"or was it Alice
     
  17. matamoros

    matamoros Funster

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    You may be right......I would need to look it up and then would probably be no wiser.........I was good at sums though:)
     
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