⚠
warning Honeywell
Error Code Replace Batt
Low battery warning — batteries are depleted or nearly depleted and need replacement.
? What Causes This
Batteries have reached end of life or are about to be depleted.
✓ How to Fix It
- Pull the thermostat from the wallplate.
- Turn it over.
- Insert fresh AA alkaline batteries.
- Reinstall the thermostat on the wallplate.
Source: page 6 of the official manual
From the manual