Thermostat shows E16 and reports remote sensor fault (for models with remote room sensors)

Safety first: Turn off power to the HVAC system before working on sensor wiring.

• Step 1 – Identify remote sensor: Locate any iComfort remote room sensors installed in other rooms.
• Step 2 – Inspect wiring: Check the low‑voltage cable from the thermostat to the remote sensor for visible damage, staples, or tight bends.
• Step 3 – Verify terminal connections: At both the thermostat and the sensor, ensure the sensor wires are on the correct terminals and firmly tightened.
• Step 4 – Test sensor resistance: Disconnect the sensor and measure its resistance with a multimeter. Compare to the iComfort sensor chart. Infinite or zero resistance indicates a failed sensor.
• Step 5 – Replace sensor: Install a new iComfort remote room sensor if the original is defective. Use twisted pair cable and avoid running parallel to high‑voltage lines.
• Step 6 – Restore power and confirm: Turn power back on and verify that E16 clears and the thermostat recognizes the remote sensor.