HVAC Code Lookup

Fujitsu Mini-Split Code 76

Soft lockoutShown as: OPERATION lamp blinks 7 times, TIMER lamp blinks 6 times, ECONOMY lamp blinking continuously

2-way or 3-way valve thermistor error. The temperature sensor on a service valve is open or short-circuited while power is on or the compressor is running.

Manual wording: “2-Way Valve Thermistor Error - When 2-way valve temperature thermistor is open or short-circuited while power is on or while running the compressor.

Documented for: RLF/RLF1, LPAS and LUAS1 multi-zone indoor units; AOU18/24/36RLXFZ and AOU24/36RML outdoor units

Likely causes, most common first

  1. Erroneous connection or removed connector at the valve thermistor
  2. Thermistor resistance out of specification
  3. Failed outdoor main PCB

What you can safely check yourself

  • Turn the power off at the outdoor disconnect and breaker for about 5 minutes, then restore power

When to call a technician

These sensors sit on the service valves inside the condenser or branch box and are ohm-checked against Fujitsu's resistance chart. That is technician work.

A Fujitsu mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Sources

Other Fujitsu codes