Daikin ยท Mini-split and VRV systems

Daikin fault codes

Daikin mini-split and VRV systems use model-specific communication, fan, sensor and temperature-protection codes. Start with power, wiring, airflow and the outdoor-unit conditions before condemning an inverter board or compressor.

How to approach a Daikin fault

  • Record the complete indoor and outdoor model numbers. The same display code can use different test points or suffixes across Daikin generations.
  • For U-series communication faults, verify terminal-to-terminal wiring, cable continuity and outdoor-unit power before replacing a control PCB.
  • A fan, discharge-temperature or pressure-protection code should be diagnosed with the outdoor coil, airflow and refrigerant circuit in mind, not treated as an isolated sensor failure.
  • Isolate power before opening a unit. Inverter equipment can retain dangerous voltage after the disconnect is opened.
Quick reference

All Daikin fault codes

Every Daikin fault code and error message we cover, with the alarm it indicates. Select a code for symptoms, ordered diagnosis, safety guidance and repair costs.

Code Fault Severity
E7 Outdoor Unit Fan Motor Fault 4/10
F3 Abnormal Discharge Pipe Temperature 5/10
U4 Communication Fault Between Indoor and Outdoor Units 4/10
Priority guides

Daikin codes to check first

The most useful starting points for common, high-impact faults.

Need a code not listed?

Start with the exact model and controller family, then use the manufacturer's service or installation manual to confirm the code. Equipment codes are not universal: the same letters or numbers can mean different things on different brands and generations.

Browse every equipment guide