Thermostat underheats; room never reaches setpoint even though heater runs

Safety: Software checks can be done with power on. Turn off power only if changing wiring or heaters.

Steps to troubleshoot underheating:

• 1. Check setpoint limits: In the thermostat menu, verify that the maximum room and floor temperature limits are not set too low.
• 2. Review schedules: Ensure that schedules are not keeping the thermostat in a constant setback (ECO) mode with low setpoints.
• 3. Confirm heater sizing: Calculate the required wattage for the room (typically 10–15 W per square foot for electric baseboard, depending on insulation). Compare with the installed Stelpro heater wattage.
• 4. Inspect heater performance: Ensure the heater warms evenly along its length and that airflow is not blocked by furniture or drapes.
• 5. Adjust floor limits (floor heating): If using a floor sensor, increase the maximum floor temperature limit within safe bounds for your floor covering.
• 6. Add or upgrade heaters: If the installed capacity is insufficient, add additional Stelpro heaters or replace with higher-wattage models as per electrical code.

Note: Poor insulation, drafts, and large windows can significantly increase heating demand; address building envelope issues where possible.