Backwards Thermostat????

Discussion in 'Shop Talk' started by shadowwalker, Mar 23, 2005.

  1. shadowwalker

    shadowwalker Well-Known Member

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    I figure there is a way to make a thermostat complete a circut. and go off when it's too cold. I need to make a alarm for my greenhouse. Could anyone help? I want to make the alarm go off in my house. shadowwalker
     
  2. farminghandyman

    farminghandyman Well-Known Member Supporter

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    I have used a line voltage thermostat, (or a snap action one) and a pezo buzzer and a 9 volt battery to do jsut what your talking about for a friend, I think he set it on 45 to 50 and it will click on as if it is calling for heat and the buzzer will go off,
     

  3. comfortablynumb

    comfortablynumb Well-Known Member

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    for that matter you can tie the thermostat to anything... a light, a buzzer or a neon sign. wen the temp hits its low limit it will click on to turn on the heat bit the thing doesnt know a furnace from a mushroom...

    hooked to a red flashing light would be very effective.
     
  4. Ross

    Ross Moderator Staff Member Supporter

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    Furnace themostats run on 14v AC so it would be ideal as is to ring a door bell or buzzer, and you could even position it a fair distance from the greenhouse as it uses AC current from a transformer. Should be very straight forward, wired the same as for your furnace only the thremostat ends on a buzzer, instead of the control box. For that matter you could run it to a furnace burner control box (jumper the flame sensor screws) and it will kick it up to 120vAC on the orange output wire, so you could power more than a buzzer. (DO NOT jumper the flame sensor screws if it is still controlling/mounted to, a furnace burner though!!!)
     
  5. Yankee1

    Yankee1 Well-Known Member

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    use a thermostat for an Air conditioning unit.
     
  6. farminghandyman

    farminghandyman Well-Known Member Supporter

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    an AC (air conditioniong) thermostat closes on heat rise,

    be great for it you want to know if it is to hot,
    but you want a heating one for the cold side, as it closes on heat drop,
     
  7. shadowwalker

    shadowwalker Well-Known Member

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    Thanks all, this really helps out. shadowwalker