Indoor unit shows F1 and may continue to run with poor temperature control.

Safety first: Turn OFF power before accessing the indoor PCB area.

• Step 1 – Locate sensor: The T1 sensor is usually near the air intake grille on the indoor unit. Remove the front cover to access it.
• Step 2 – Check mounting: Ensure the sensor bulb is properly clipped in place where return air passes over it, not hanging loose inside the casing.
• Step 3 – Inspect wiring: Follow the sensor wires to the indoor PCB. Reseat the connector and check for damage or corrosion.
• Step 4 – Replace sensor: If F1 persists, replace the indoor ambient sensor with the correct Klimaire part. Route the new sensor wiring exactly as the original to avoid interference.