Unit does not respond to changes in temperature setting; room becomes too cold or too warm.

Safety: Unplug the unit before accessing the sensor or control board.

Steps:

• 1. Verify with thermometer: Compare the unit's displayed temperature with an accurate room thermometer. Note any large difference.
• 2. Inspect sensor location: Ensure the room thermistor is in the return air path and not touching the cold coil or near heat sources.
• 3. Test sensor: Measure resistance at known temperatures and compare to the Frigidaire spec chart. Replace if out of range.
• 4. Control board: If the sensor is accurate but the unit still overshoots or undershoots, the main control board may be misreading and should be replaced.