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airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 8264
Experience:  Furnace, A/C and heat pump specialist.
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I have a wall heater. I am installing a new 240 Line voltage

Customer Question

I have a wall heater. I am installing a new 240 Line voltage thermostat, Single pole. I was dumb and unhooked the old thermostat wires before labeling them. The white is already hooked up(white to white). My problem comes that the other 2 wires in the wall box are black. How do I find out which wire is Power and which is Heater?
Submitted: 1 year ago.
Category: HVAC
Expert:  airheatman replied 1 year ago.

If you have a volt meter we can check between White and each black to see which has power on it.

Expert:  airheatman replied 1 year ago.

That is the proper way to determine.You can get an inexpensive meter at Walmart for about 15 bucks if you do not have one.