Furnace displays E10, blower may run continuously, no heat output.

Safety: Turn off power before accessing the blower or supply plenum.

Steps:

• Locate the sensor: The supply air temperature sensor (thermistor) is typically mounted in the supply plenum or on the heat exchanger outlet panel.
• Inspect wiring: Check the sensor leads and connector for damage, burns, or loose connections. Reseat the connector on the control board.
• Check resistance: Using a multimeter, measure the sensor resistance at room temperature and compare it to the values in the Atlantic service manual. An open (infinite) or shorted (near 0 Ω) reading indicates a bad sensor.
• Replace if faulty: If the sensor is out of specification, replace it with an Atlantic-approved supply air temperature sensor.

Note: After replacement, clear the error by cycling power and verify normal operation.