Wire My ThermostatAmazon Smart Thermostat wiring for 2-stage heat + 2-stage cool
The Amazon Smart Thermostat is not compatible with this setup. See the alternatives below.
W2 and Y2 mean a two-stage furnace and a two-stage AC. They run on low most of the time and step up on extreme days. Budget thermostats can’t run the second stages.
1Snap a photo of your old thermostat’s wires (optional)
AI reads the terminal letters and wire colors, then you double-check them. Photos are not saved.
2Tick every terminal that has a wire
Pull the faceplate off your old thermostat. Use the letter printed next to each wire, not its color. Skip short jumper wires between two terminals.
More labels (W3, X, X2, K, PEK, L, S, T, U, HUM, DEHUM)
3A few quick questions
4Your wiring
Which smart thermostats work with your wires?
Amazon Smart Thermostat
Not compatible| Wire | Color | Job | Connect to | Note |
|---|---|---|---|---|
| R | red | 24 V power | R | |
| C | blue | Common (C wire) | C | |
| W1 | white | Heat, stage 1 | W | |
| W2 | brown | Heat, stage 2 | Don’t connect | No matching terminal on the Amazon Smart Thermostat |
| Y1 | yellow | Cooling, stage 1 | Y | |
| Y2 | orange | Cooling, stage 2 | Don’t connect | No matching terminal on the Amazon Smart Thermostat |
| G | green | Fan | G |
Install steps
- Turn off power to the furnace/air handler (switch or breaker) and the AC condenser. Confirm the old thermostat is dead.
- Photograph the old wiring, then label each wire with the letter it came off. Ignore short jumpers.
- Connect each wire to the Amazon Smart Thermostat terminal shown above. Cap unused wires one at a time.
- Restore power and finish setup in the app using the settings below.
- Test heat, cool and fan. If a breaker trips or equipment runs nonstop, power off and call a pro.
App settings to choose
- Set the number of heat and cool stages to match the wires connected.
What you need
- Amazon Smart ThermostatThe thermostat itselfCheck price
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Confirm against the official Amazon install guide. The app also checks your wiring during setup.
Frequently asked questions
Where does each wire go on the Amazon Smart Thermostat?
R → R; C → C; W1 → W; W2 → not connected; Y1 → Y; Y2 → not connected; G → G.
Do I need a C wire for the Amazon Smart Thermostat?
You already have a C wire, so no adapter is needed.