Will my existing Honeywell unit be compatible with the wiring scheme for this thermostat?
The Honeywell RTH8580WF should replace an existing Honeywell unit very easily. In fact, you can view the quick start guide with wiring diagram here.

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This product is listed under the following manufacturer number(s):
*Denotes a finish or option that has been discontinued
The Honeywell RTH8580WF should replace an existing Honeywell unit very easily. In fact, you can view the quick start guide with wiring diagram here.
| Supports Heat Pump | Yes |
|---|---|
| Voltage | 24 |
| Controls | Digital |
| Programmable | Yes |
| Stages | 2 Heat / 2 Cool |
| Height | 3.5 |
| Large Display | Yes |
| Supports Gas | Yes |
| Auto Changeover | Yes |
| Width | 5.875 |
| Supports Millivolt | Yes |
| Supports Oil | Yes |
| Fan Switch | Auto, On |
| Display Size | 2.5 |
| Supports Electric | Yes |
| Depth | 1.5 |
| Hardwired | Yes |
| Supports 24 Volts | Yes |
| Backlit | Yes |
| Programming | Multi-Function |
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