Daikin · Mini-split
U2 Power supply / voltage abnormality
What this code means
The system is detecting abnormal supply voltage or a momentary power interruption.
Most likely causes
- Brownout or power surge event
- Faulty main circuit wiring
What to try first
Power-cycle at the breaker; if it recurs, this needs an electrician to check supply voltage.
Safety note: if this code returns after one clean reset, stop resetting it — repeated lockouts usually mean a real fault that needs a licensed technician. Never bypass a safety switch.
FAQ
What does Daikin error code U2 mean?
Power supply / voltage abnormality. The system is detecting abnormal supply voltage or a momentary power interruption.
Can I fix Daikin code U2 myself?
Usually not. Power-cycle at the breaker; if it recurs, this needs an electrician to check supply voltage. If the code returns after one reset, it needs a licensed technician.
What causes Daikin code U2?
The most common causes are: brownout or power surge event; faulty main circuit wiring.
Other Daikin mini-split codes
All Daikin mini-split error codes →
Other mini-split brands: Mitsubishi · LG · Fujitsu · Gree · Carrier · Generic · Panasonic
This information may contain errors or not apply to your exact model — always double-check it against your appliance's own manual before acting. If there's any chance of a gas, fire, electrical, carbon monoxide, or other safety hazard, stop and call a licensed professional or the appropriate agency (e.g. your gas utility) instead of relying on this page alone.