What each Daikin code means — and what to do next. Stuck? AAA Comfort Air fixes Daikin systems across Central NJ, often same-day.
Daikin is the world’s largest HVAC maker and a leader in ductless and inverter technology. Daikin systems self-diagnose and display an alphanumeric code.
Press the remote’s cancel/inspection button (or read the indoor LED) to show the code — a letter plus two digits. The indicator is a alphanumeric code (letter + 2 digits, e.g., U0, U4, E1, A5).
| Code | What it means | What to do |
|---|---|---|
| E1 | Outdoor unit control board (PCB) fault | Call us |
| U0 | Low refrigerant / possible leak | Needs an EPA-certified tech — call us |
| U4 | Indoor–outdoor communication error | Wiring/terminal/PCB — call us |
| A5 | Freeze-up / high-pressure protection | Airflow/refrigerant — call us |
| A6 | Indoor fan motor fault | Call us |
⚠️ Codes can vary by model and control-board revision — always confirm against the label inside your unit’s access panel. For any gas, electrical, or refrigerant fault, call a licensed technician.
Press the remote’s cancel/inspection button (or read the indoor LED) to show the code — a letter plus two digits.
You can try one power cycle at the breaker to clear a one-time fault. But if the same code returns, it’s a real fault — repeatedly resetting a gas or electrical issue can be unsafe. Call AAA Comfort Air at 609-665-3022.
AAA Comfort Air installs and repairs Daikin systems across Cream Ridge and Central New Jersey, with same-day and 24/7 emergency service. Call 609-665-3022.
Book online or call your local Daikin HVAC team — same-day & 24/7 emergency service.
