Thermostat displays E18 and cannot detect or pair with a Bluetooth setup device (on models using BLE for initial setup).

Safety: No electrical work is required.

• Move closer: Stand within a few feet of the thermostat with your phone during pairing.
• Reduce interference: Temporarily turn off nearby Bluetooth devices that may interfere.
• Check settings: On the thermostat, ensure Bluetooth or "Local Setup" is enabled in the installer menu.
• Reboot devices: Restart both the thermostat (via power cycle) and your phone, then retry pairing.
• Replace thermostat: If E18 persists and Bluetooth remains undiscoverable, the internal BLE module is likely defective and the thermostat should be replaced.