How to Wire a Heat Pump With Two Wires
- 1). Remove the thermostat's main display piece by hand to reveal its interior.
- 2). Separate the two wires of the heat pump by hand. There should be a black wire that controls the heat pump's power, and an orange wire that controls the heat pump's reversing valve. Run both wires through the thermostat's opening in the middle.
- 3). Attach the black wire to the "C" terminal of your thermostat's wiring block by hand. Your thermostat now has power from the heat pump.
- 4). Attach the orange wire to the "O/B" terminal of the wiring block by hand. The heat pump reversing valve can now provide both heating and cooling power to the thermostat.
- 5). Replace the thermostat's display piece by hand. Turn the thermostat on and set it to either "Cooling" or "Heating" to use the heat pump.
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