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mdmale35
Dec 26, 2007, 12:35 PM
Hi,

I am replacing a old double pole wall thermostat to a built in 240 volt space heater. I purchased a new 240 volt heater which came with a single pole wall thermostat.

I removed the old double pole thermostat and have 2 black & 2 red wires when the single pole only has 1 black wire in and one black wire out. How do I make this work? Can I simply take the 2 black wires in (110v each) & wire nut them together to feed the thermostat?

My eletrical box in the basement I see I have a double breaker feeding the thermostat.

I am used to working with 110 but have not done any 240 volt wiring before.

Thanks,
Rob

hvac1000
Dec 26, 2007, 12:40 PM
If you are feeding a 220 volt heater you can usually tie one set REDs OR blacks together and then feed the one set you did not use to the thermostat and heater.

All you are doing is eliminating one of the switch legs. Always use a meter and check everything before you wire it up.