Fujitsu Mini-Split: 10 Flashes
A Fujitsu mini-split LED pattern starting with 10 flashes matches 3 documented codes: A1, A3, A5. Watch the full pattern (short vs. long flashes) to tell them apart — all 3 are explained below.
Code A1: Discharge temperature error
Discharge temperature error. The compressor discharge line reached 230 F (110 C) during operation twice within 24 hours, so the system stopped to protect the compressor.
Manual wording: “Discharge Temperature Error - Protection stop by discharge temperature 230F (110C) during compressor operation generated 2 times within 24 hours.”
Documented for: RL2, RLS2, RLS3, RLB/RLXB, RLF, RLF1, RGLX, RLE, LUAS1, LMAS, LZBS, LZAS, LPAS series
Likely causes, most common first
- Closed or partly closed 3-way service valve
- Restricted electronic expansion valve or clogged strainer
- Outdoor fan or heat exchanger not rejecting heat (dirty coil, blocked airflow)
- Low refrigerant charge or a refrigerant leak
- Failed discharge thermistor
What you can safely check yourself
- Clear anything blocking airflow at the outdoor unit - leaves, snow, stored items, overgrown shrubs
- Check the outdoor coil for heavy dirt or cottonwood buildup
- Turn the power off at the disconnect for about 5 minutes, then restore power
When to call a technician
Fujitsu's checklist is service valves, expansion valve, strainer, and a leak check with gauges. All of that is licensed refrigeration work - do not open service valves yourself.
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
- Discharge Temperature Error - Fujitsu General Help Center (Fujitsu General America, Inc., RL2, RLS3, RLS2, RLB/RLXB, RLF, RLF1, LUAS1, LMAS, LZBS, LZAS, LPAS, RGLX, RLE series) · checked 2026-08-25
Code A3: Compressor temperature error
Compressor temperature error. The compressor body reached 226 F (107.8 C) during operation twice within 24 hours and the system stopped to protect it.
Manual wording: “Compressor Temperature Thermistor Error - Protection stop by compressor temperature 226F (107.8C) during compressor operation generated 2 times within 24 hours.”
Documented for: RL2, RLS2, RLS3, RLB/RLXB, RLF, RLF1, RGLX, RLE, LUAS1, LMAS, LZBS, LZAS, LPAS series
Likely causes, most common first
- Closed or partly closed 3-way service valve
- Restricted electronic expansion valve or clogged strainer
- Outdoor fan or heat exchanger not rejecting heat
- Low refrigerant charge or a leak
- Loose connection at the compressor thermistor
What you can safely check yourself
- Clear leaves, snow, and debris from around the outdoor unit and off the coil
- Turn the power off at the disconnect for about 5 minutes, then restore power
When to call a technician
Service valve position, expansion valve, strainer and charge level all require gauges and a refrigeration license. Call a technician.
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
- Compressor Temperature Error - Fujitsu General Help Center (Fujitsu General America, Inc., RL2, RLS3, RLS2, RLB/RLXB, RLF, RLF1, LUAS1, LMAS, LZBS, LZAS, LPAS, RGLX, RLE series) · checked 2026-08-25
Code A5: Low pressure error
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