Honeywell Error Code E2: Sensor Fault
How to Fix Honeywell Code E2
- Step 1: Turn the system off and then back on. This might reset the control board and clear a temporary error.
- Step 2: Check the air filter. A very dirty air filter can sometimes cause unusual temperature readings. Replace it if needed.
- Step 3: If the error persists after these steps, it's best to call a qualified HVAC technician for diagnosis and repair.
How to Reset Honeywell Code E2
- Remove the thermostat from its wall plate.
- Remove the batteries and wait 30 seconds.
- Reinsert the batteries and snap the thermostat back onto the wall plate.
- If the error persists, perform a factory reset through the menu: Menu > Preferences > Restore Factory Defaults.
What does E2 mean?
The 'E2' error code on your Honeywell HVAC system indicates a problem with one of its temperature sensors. These sensors are like the system's eyes and ears, constantly monitoring temperatures to ensure everything is running smoothly and efficiently. When a sensor malfunctions or the control board loses communication with it, the system can't accurately regulate heating or cooling. This can lead to the unit shutting down, providing inconsistent temperatures, or running inefficiently. The E2 code specifically points to a fault in either the supply air temperature sensor or the return air temperature sensor. These sensors are thermistors, meaning their resistance changes with temperature. The control board reads these resistance changes to determine the air temperature.
Affected Models
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| Supply Air Temperature Sensor | — | — |
| Return Air Temperature Sensor | — | — |
| Control Board | — | — |