Safety: Turn off power at the breaker before removing the thermostat from the wall.

Steps to troubleshoot E14 (calibration error):

1. Verify location: Ensure the thermostat is installed on an interior wall, away from drafts, direct sunlight, and heat sources. Relocate if necessary.
2. Compare temperatures: Place an accurate room thermometer near the thermostat and compare readings. Note any large discrepancies.
3. Adjust offset: Many Stelpro smart thermostats allow a temperature offset in the settings. Apply a small offset to match the reference thermometer.
4. Factory reset: Perform a factory reset to clear corrupted calibration data, then reconfigure the thermostat.
5. Firmware update: Update to the latest firmware via the Stelpro app to ensure you have the latest control algorithms.
6. Replace thermostat: If E14 persists and the temperature reading is clearly wrong even after offset and reset, the internal sensor or ADC on the board is likely defective. Replace the thermostat.

Note: Do not attempt to manually recalibrate internal sensors beyond the offset provided in the menu.

Thermostat shows E14 and heating cycles erratically or not at all

Possible Causes