F2
Daikin Split AC
Severity: ModerateWhat Does This Error Mean?
F2 on a Daikin AC means the outdoor ambient temperature thermistor has a fault. This sensor measures the outside air temperature so the inverter can adjust its operation for conditions. When the sensor fails or reads an impossible value, F2 triggers and the system stops.
Affected Models
- Daikin FTKF Series
- Daikin FTKG Series
- Daikin ATKF Series
- Daikin Inverter Split AC (all models)
- Daikin 1 Ton / 1.5 Ton / 2 Ton Inverter
Common Causes
- Outdoor ambient thermistor failed — resistance reading outside specification
- Thermistor wire damaged by UV, rain, or rodent activity near the outdoor unit
- Thermistor connector at the outdoor PCB corroded from humidity or moisture
- Thermistor probe not positioned correctly to read ambient outdoor air temperature
- Outdoor PCB fault — misreading a valid thermistor signal
How to Fix It
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Turn off the AC at the remote and cut power at the circuit breaker. Wait 5 minutes.
A power cycle clears transient errors. Restore power and restart — if F2 does not return, monitor over the next few cycles.
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Check the outdoor unit for obvious damage — pest activity, water pooling, physical impact.
Rodents frequently chew thermistor wiring inside outdoor units. If you see evidence of pests, mention this when booking a technician.
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If F2 persists, call Daikin service — the outdoor ambient thermistor needs testing.
The repair is typically inexpensive. The main cost is the service visit fee.
When to Call a Professional
F2 requires a Daikin authorised technician. The outdoor unit contains high-voltage capacitors that remain dangerous even after power off. Daikin India: 1800-103-3666. A technician will test thermistor resistance and replace the sensor if needed.
Frequently Asked Questions
Does Daikin F2 appear more often in very hot weather?
Yes — in extreme heat (above 50 degrees C outdoor temperature), the ambient thermistor can read at the edge of its range. A thermistor that is already slightly degraded will tip into a fault reading under extreme conditions. Ensure the outdoor unit has full ventilation clearance on all sides.