Status code99Fujitsu
What does Fujitsu 99 mean?
4-way valve error: heat-exchanger temperature and room temperature stay too far apart for the mode. The operation lamp blinks 9 times and the timer lamp blinks 9 times.
Call a pro: jump to when to call a pro Equipment type: mini-split
How it shows: ASUG09LZAS, ASUG12LZAS or ASUG15LZAS. Operation lamp (green) blinks 9 times, timer lamp (orange) blinks 9 times, economy lamp (green) flashes continuously. Wired controller shows 99.
Likely causes
- Connector connection failure
- Thermistor failure
- 4-way valve coil failure
- 4-way valve failure
- Main PCB failure
Safe checks for 99
- Leave the unit off at the breaker and the outdoor disconnect. The valve is in the refrigerant circuit
- If the same condition repeats 5 times, the manual says the compressor stops permanently until it is repaired
Safety firstIndoor and outdoor mini-split units carry line voltage even when the remote is off. Switch off the outdoor disconnect and the breaker before you touch the unit, and do not open either cabinet. Refrigerant, wiring and control-board work must be done by a licensed HVAC technician.
Capacitors can hold a charge after the power is off. Safety terms.
When to call a pro
A 9-and-9 blink is not a thermostat setting. Call a licensed HVAC technician. Do not open service valves.
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