The following table covers the terminal descriptions of the HVAC systems that are compatible with our Smart Thermostat. Refer to the presence of the mentioned terminals to identify the existing HVAC system and validate the connections after wiring:
| Equipment Type | Terminal | Description | Note |
| Furnace | W1 | Heat (1st stage) | – |
| W2 | Heat (2nd stage) | – | |
| G | Fan | – | |
| RH | 24 VAC/230 VAC | – | |
| Boiler | W1 | Heat (1st stage) | – |
| W2 | Heat (2nd stage) | – | |
| RH | 24 VAC/230 VAC | – | |
| G | Fan | – | |
| Air Conditioner | Y1 | Cool (1st stage) | – |
| Y2 | Cool (2nd stage) | – | |
| G | Fan | – | |
| RC | 24 VAC/230 VAC | – | |
| Furnace/Boiler and Air Conditioner | Y1 | Cool (1st stage) | |
| Y2 | Cool (2nd stage) | ||
| W1 | Heat (1st stage) | ||
| W2 | Heat (2nd stage) | ||
| G | Fan | ||
| RC | 24 VAC/230 VAC | ||
| RH | 24 VAC/230 VAC | If RH is not available, connect it with RC by using a jumper wire. | |
| Heat Pump | Y1 | Cool/Heat (1st stage) | – |
| Y2 | Cool/Heat (2nd stage) | – | |
| G | Fan | – | |
| O/B | Reversing valve for heat pump | – | |
| RC | 24 VAC/230 VAC | – | |
| Heat Pump with Aux Heat | Y1 | Cool/Heat (1st stage) | – |
| Y2 | Cool/Heat (2nd stage) | – | |
| W1 | Aux heat (1st stage) | – | |
| W2 | Aux heat (2nd stage) | – | |
| G | Fan | – | |
| O/B | Reversing valve for heat pump | – | |
| RC | 24 VAC/230 VAC | – | |
| RH | 24 VAC/230 VAC | If RH is not available, connect it with RC by using a jumper wire. | |
| FCU 2-Pipe Cool Only | Y1 | Cool | – |
| GL | Fan Speed Low | Connect to this terminal if there is only one fan wire | |
| GM | Fan Speed Medium | Connect if the multi-speed fan is available and three fan wires exist | |
| GH | Fan Speed High | Connect if the multi-speed fan is available and two fan wires exist | |
| RC | 24 VAC/230 VAC | – | |
| FCU 2-Pipe Heat Only | Y1 | Heat | – |
| GL | Fan Speed Low | Connect to this terminal if there is only one fan wire | |
| GM | Fan Speed Medium | Connect if the multi-speed fan is available and three fan wires exist | |
| GH | Fan Speed High | Connect the secondary heating source, like an electric heater, etc. | |
| RC | 24 VAC/230 VAC | – | |
| FCU 2-Pipe Heat or Cool with Aux Heat | Y1 | Heat/Cool | Connect either Heat or Cool |
| W1 | Aux Heat | Connect if the multi-speed fan is available and two fan wires exist | |
| GL | Fan Speed Low | Connect to this terminal if there is only one fan wire | |
| GM | Fan Speed Medium | Connect if the multi-speed fan is available and three fan wires exist | |
| GH | Fan Speed High | Connect if the multi-speed fan is available and two fan wires exist | |
| RC | 24 VAC/230 VAC | – | |
| RH | 24 VAC/230 VAC | If RH is not available, connect it with RC by using a jumper wire. | |
| FCU 4-Pipe Heat and Cool | Y1 | Cool | If only cool is available, that can be connected to make it cool only system. |
| W1 | Heat | If only heat is available, that can be connected to make it heat only system. | |
| GL | Fan Speed Low | Connect to this terminal if there is only one fan wire | |
| GM | Fan Speed Medium | Connect if the multi-speed fan is available and three fan wires exist | |
| GH | Fan Speed High | Connect if multi-speed fan is available and three fan wires exist | |
| RC | 24 VAC/230 VAC | – | |
| RH | 24 VAC/230 VAC | If RH is not available, connect it with RC by using a jumper wire. | |
| Power | L | 230 VAC | Must be connected to power the HVAC Controller. |
| N | – | Must be connected to power the HVAC Controller. | |
Note: You do NOT need to make any connection with the Common terminal.