Fujitsu Mini-Split Code A5
Soft lockoutShown as: OPERATION lamp blinks 10 times, TIMER lamp blinks 5 times, ECONOMY lamp blinking continuously
Low pressure error. Suction pressure stayed at or below 7.35 PSI for 5 minutes, repeating 5 times within 2 hours, so the system stopped.
Manual wording: “Low Pressure Error - Protection stop by suction pressure 7.35 PSI continued for 5 minutes, repeats 5 times within 2 hours.”
Documented for: Single-zone (1-to-1) matched systems; RGLX, RLS3/RLB/RLXB, RLF/RLF1
Likely causes, most common first
- Closed or partly closed 3-way (gas side) service valve
- Clogged strainer
- Failed electronic expansion valve coil
- Low refrigerant charge or a refrigerant leak
- Failed suction pressure sensor
What you can safely check yourself
- Note the outdoor temperature when the code appeared - Fujitsu says this code only shows up when outdoor ambient drops below 32 F
- Turn the power off at the disconnect for about 5 minutes, then restore power
When to call a technician
Fujitsu classes A5 as a fix-on-fail code that must be serviced on site by a licensed technician, with running pressures checked on gauges and a leak check performed. It also requires function setting F3-40 to fully reset.
A Fujitsu mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- 410A Mini-Split Troubleshooting Guide (Part # 6-26-FG2020 Rev. 5/2019) (Fujitsu General America, Inc., All R410A Halcyon mini-splits: RGLX, RL2/RLS3/RLS3H/RLS3Y/RLB/RLXB/RLXEH wall mounted, RLF/RLF1 multi-zone indoor units, RLXFZ multi-zone outdoor units, RML/RMLQ, RULX/RSLX universal-mount, RCLX cassettes) · checked 2026-08-25
- S Bulletin 044 - A5 Error Code - Fujitsu General Help Center (Fujitsu General America, Inc., Single-zone (1-to-1) Halcyon systems) · checked 2026-08-25