Thermostat overshoots set temperature and room becomes too hot

Safety: Most adjustments are in software; power-off is only needed if relocating the thermostat.

Steps to reduce overshoot:

• 1. Check thermostat location: Ensure it is not above a heater, near a window, or behind curtains. Relocate to an interior wall about 1.5 m (5 ft) above the floor if necessary.
• 2. Enable adaptive control: In the Stelpro app or thermostat menu, enable any available adaptive or proportional control modes instead of simple on/off.
• 3. Adjust cycle settings: If the thermostat allows, reduce the cycle rate or increase the proportional band to smooth temperature swings.
• 4. Use floor sensor (if applicable): For floor heating, ensure the floor sensor is connected and the thermostat is configured to use it, especially if the floor covering is temperature-sensitive.
• 5. Verify sensor accuracy: Compare the thermostat reading with a reliable thermometer. If the reading is off by more than 1–2°C, apply a temperature offset in the settings.
• 6. Replace thermostat: If overshoot persists despite correct placement and settings, the internal sensor or control algorithm may be faulty. Replace the thermostat.

Note: Some overshoot is normal in high-mass systems like concrete slab heating; adjust expectations accordingly.