How House Works

Fujitsu mini-split error codes and blink codes

63 codes for KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPAS, RLS3, RLS3Y, RLB, RLS2, RLF1, RL2, each with the wording and page from Fujitsu's manuals.

By How House Works EditorialBased on Fujitsu manualsChecked against sources Updated

All Fujitsu codes

Meanings are quoted from Fujitsu's manuals. The "Who" column is our reading of themanual's remedy: whether an owner can do the first checks, or the fix belongs to a licensed technician.

CodeManual meaningSeriesWhoSource
11“Serial communication error (Serial reverse transfer error) (Outdoor unit)”
What to check
OPERATION 1 / TIMER 1. The indoor unit gets no serial signal from the outdoor unit for more than 2 minutes after power-on, or for more than 15 seconds during normal operation (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-24). KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “Serial communication error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
11“Serial communication error (Serial forward transfer error) (Indoor unit)”
What to check
OPERATION 1 / TIMER 1, the same blinks as the reverse transfer error. The outdoor unit cannot properly receive the indoor unit's serial signal for 10 seconds or more (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-26). KNAS prints it without “(Indoor unit)”.		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
11“Serial communication error”
What to check
OPERATION 1 / TIMER 1. The service instructions split it into a reverse and a forward transfer error with the same blinks (RLS3 Service Instructions, pp. 02-03–02-04).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
12“Wired remote controller communication error (Indoor unit)”
OPERATION 1 / TIMER 2. Not in the KNAS or ASLH service manual tables. The LZBS installation manual adds “Server room control communication error” to this line (LZBS Installation Manual, p. En-11).		KPAS, KPBS, KMAS, KZAS, KTAS, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
12“Wired remote control communication error”
OPERATION 1 / TIMER 2. The RLB installation manual says “Wired remote controller communication error” (RLB Installation Manual, p. En-11).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14
15“Automatic airflow adjustment error”
OPERATION 1 / TIMER 5. Among the K and L service manuals, only the KNAS table has 15. The KPAS and LZBS installation manuals list “Check run unfinished Automatic airflow adjustment error” (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11).		KNASTechnicianKNAS service p. 03-2
15“Check run unfinished”
OPERATION 1 / TIMER 5. The RLB service manual table, marked “under confirmation”, calls it “Scan error” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14
16“Peripheral unit transmission PCB connection error”
OPERATION 1 / TIMER 6. Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLS3Y install p. En-11; RLF1 install p. En-13
18“External communication error (Indoor unit)”
OPERATION 1 / TIMER 8. The KPAS/KPBS check covers the connection to the WLAN adapter, then the adapter, then the main PCB (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-29). The LZBS and LZAS tables add three more 18 lines for the wireless LAN adapter (LZBS Service Manual SR_AS048EF_02, p. 03-2; LZAS Service Manual SR_AS024EF_09, p. 03-2). KNAS prints it without “(Indoor unit)”. Also in the RLS3Y and RLF1 installation manual lists (RLS3Y Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
18“External Communication Error”
OPERATION 1 / TIMER 8. The RLS3Y service instruction lists it with a check section (RLS3Y Service Instruction, p. 02-09); the RLS3Y service manual table does not have 18 (RLS3Y Service Manual, p. 7). The RLS3Y installation manual says “External communication error” (RLS3Y Installation Manual, p. En-11).		RLS3YTechnicianRLS3Y service instr. p. 02-01
21“Unit number or Refrigerant circuit address setting error [Simultaneous Multi]”
OPERATION 2 / TIMER 1. Also in the KPAS and LZBS installation manual lists, ending “[simultaneous multi-split type]” (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table. The RLB service manual table, marked “under confirmation”, says “Initial setting error (for simultaneous multi)” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
22“Indoor unit capacity error (Indoor unit)”
What to check
OPERATION 2 / TIMER 2. Condition: “When the total capacity of the indoor units does not match outdoor unit capacity while 3 minutes after power on.” (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-30). KNAS prints it without “(Indoor unit)”. Not in the L service manual tables.		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLHTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2
22“Indoor unit capacity error”
What to check
OPERATION 2 / TIMER 2. The service instructions for these lines have no check section for 22 (RLS3 Service Instructions, p. 02-01; RLS3Y Service Instruction, p. 02-01; RLB Service Instructions, p. 02-01; RLS2 Service Instructions, p. 02-01; RLFW1 Service Instruction, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14
23“Combination error (Outdoor unit)”
OPERATION 2 / TIMER 3. KNAS: “Refrigerant combination error” (KNAS Service Manual SR_AS159ES_02, p. 03-2). Not in the L service manual tables.		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLHTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2
23“Combination error”
OPERATION 2 / TIMER 3. The RLB service manual table, marked “under confirmation”, says “Connection disabled (series error)” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14
24“• Connection unit number error (indoor unit) [Simultaneous Multi] • Connection unit number error (indoor unit or branch unit) [Flexible Multi]”
OPERATION 2 / TIMER 4, the example the KPAS installation manual uses to explain blink counts (KPAS Installation Manual, p. En-16). RLS3Y and RLB say “(indoor secondary unit)” in the first line (RLS3Y Service Manual, p. 7; RLB Installation Manual, p. En-11). Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
26“Address setting error in wired remote controller (Indoor unit)”
OPERATION 2 / TIMER 6. Not in the KNAS, ASLH or L service manual tables. KPAS installation manual: “Indoor unit address setting error” (KPAS Installation Manual, p. En-16); the RLS3Y and RLF1 installation manual lists have it too (RLS3Y Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KMAS, KZAS, KTASTechnicianKPAS/KPBS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2
27“Primary unit, secondary unit set-up error [Simultaneous Multi]”
OPERATION 2 / TIMER 7. RLF1: “Master unit,slave unit set-up error [Simultaneous Multi]” (RLF1 Service Manual, p. 14). Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
29“Connected unit number error (Indoor unit)”
OPERATION 2 / TIMER 9. KNAS prints it without “(Indoor unit)”. Not in the ASLH or L service manual tables. KPAS installation manual: “Connection unit number error in wired remote controller system” (KPAS Installation Manual, p. En-16); the RLS3Y and RLF1 installation manual lists have it too (RLS3Y Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KNAS, KMAS, KZAS, KTASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2
31“Power supply interruption error”
OPERATION 3 / TIMER 1. Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLS3Y install p. En-11; RLF1 install p. En-13
32“Indoor unit main PCB error (Indoor unit)”
OPERATION 3 / TIMER 2. KNAS prints “Indoor unit Main PCB error” (KNAS Service Manual SR_AS159ES_02, p. 03-2). KPAS installation manual: “Indoor unit PCB model information error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
32“Indoor unit PCB model information error”
OPERATION 3 / TIMER 2. RLS3 service instructions: “Indoor Unit Model Information Error / EEPROM Access Abnormal” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
33“Indoor unit motor electricity consumption detection error (Indoor unit)”
OPERATION 3 / TIMER 3. KNAS prints it without “(Indoor unit)”. Not in the L service manual tables; the RLF1 installation manual list has it (RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLHTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2
35“MANUAL AUTO button error (Indoor unit)”
OPERATION 3 / TIMER 5. KNAS prints it without “(Indoor unit)”. KPAS installation manual: “Manual auto switch error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
35“Manual auto switch error”
OPERATION 3 / TIMER 5.		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
39“Indoor unit power supply error for fan motor (Indoor unit)”
OPERATION 3 / TIMER 9. KNAS: “Power supply error of indoor unit fan motor” (KNAS Service Manual SR_AS159ES_02, p. 03-2). Not in the L service manual tables; the RLF1 installation manual list has it (RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLHTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2
3A“Indoor unit communication circuit (wired remote controller) error”
OPERATION 3 / TIMER 10 (A = 10 blinks). KNAS: “Indoor unit communication circuit error” (KNAS Service Manual SR_AS159ES_02, p. 03-2). Not in the ASLH or L service manual tables; the RLS3Y and RLF1 installation manual lists have it (RLS3Y Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KPAS, KPBS, KNAS, KMAS, KZAS, KTASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2
41“Room temperature sensor error (Indoor unit)”
OPERATION 4 / TIMER 1. KNAS names 41 and 42 together: “Indoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-2, 03-40). KPAS installation manual: “Room temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
41“Room temp. sensor error”
OPERATION 4 / TIMER 1. RLS3 service instructions: “Indoor Room Thermistor Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
42“Indoor unit heat exchanger sensor error (Indoor unit)”
OPERATION 4 / TIMER 2. KNAS names 41 and 42 together: “Indoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-2, 03-40). KPAS installation manual: “Indoor unit heat ex. middle temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
42“Indoor unit Heat Ex. Middle temp. sensor error”
OPERATION 4 / TIMER 2. RLS3 service instructions: “Indoor Heat Ex.(Pipe) Thermistor Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
44“Human sensor error”
OPERATION 4 / TIMER 4. The KPAS installation manual calls it “Occupancy sensor error” (KPAS Installation Manual, p. En-16); the LZBS, RLS3Y and RLF1 installation manual lists say “Human sensor error” (LZBS Installation Manual, p. En-11; RLS3Y Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KZAS, KTASTechnicianKZAS service p. 03-2; KTAS service p. 03-2
45“Refrigerant leakage sensor error (Indoor unit)”
OPERATION 4 / TIMER 5. Only in the 2026 revision of the service manual; the earlier revision has no 45 (KPAS Service Manual SR_AS142ES_04, p. 03-2). The KPBS installation manual lists “Refrigerant leakage sensor error”, the KPAS one does not (KPBS Installation Manual, p. En-16; KPAS Installation Manual, p. En-16). Mobile app code 45.2, “Refrigerant sensor error (Malfunction)” (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-8). The check is the sensor's connector and cable, then the sensor (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-41).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-2
45“Refrigerant leakage sensor deterioration (Indoor unit)”
OPERATION 4 / TIMER 5, the same blinks as the sensor error; the table misprints the TIMER count as “5imes”. Mobile app code 45.3, “Refrigerant sensor error (End of life)” (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-8). The check is to replace the refrigerant leakage sensor (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-42).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-2
51“Indoor unit fan motor error (Indoor unit)”
What to check
OPERATION 5 / TIMER 1. Set when the indoor fan runs below 1/3 of its target speed for more than 56 seconds (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-43). KNAS prints it without “(Indoor unit)”. KPAS installation manual: “Indoor unit fan motor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
51“Indoor unit fan motor error”
What to check
OPERATION 5 / TIMER 1. The RLS3 service instructions print the same 1/3 and 56-second rule (RLS3 Service Instructions, p. 02-10).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
53“Drain pump error”
OPERATION 5 / TIMER 3. These service manual tables have no check section, and the service instructions for these lines do not cover 53 (RLS3 Service Instructions, p. 02-01; RLS3Y Service Instruction, p. 02-01; RLB Service Instructions, p. 02-01; RLFW1 Service Instruction, p. 02-01). Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table. The RLB service manual table, marked “under confirmation”, says “Water drain error” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
54“Electric air cleaner reverse VDD error (Indoor unit)”
OPERATION 5 / TIMER 4. Only the KTAS service manual table has 54. The KPAS, LZBS and RLF1 installation manual lists say “Electric air cleaner reverse VDD error” (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11; RLF1 Installation Manual, p. En-13).		KTASTechnicianKTAS service p. 03-2
55“Filter set error”
OPERATION 5 / TIMER 5. Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLF1 install p. En-13
57“Damper error”
OPERATION 5 / TIMER 7. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
58“Intake grille error (Indoor unit)”
OPERATION 5 / TIMER 8. Not in the LMAS or LPAS tables or in any K service manual table; the KPAS installation manual lists “Intake grille error” (KPAS Installation Manual, p. En-16).		LZBS, LZASTechnicianLZBS service p. 03-2; LZAS service p. 03-2
58“Intake grill error”
OPERATION 5 / TIMER 8. RLB: “Intake grille error” (RLB Installation Manual, p. En-11). The RLS3 service instructions check a limit switch, connector CN11 and the controller PCB (RLS3 Service Instructions, p. 02-11). For RLS2 see the next row.		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLF1 service p. 14
58“Intake grille error”
OPERATION 5 / TIMER 8 with ECONOMY blinking. The RLS2 owner's manual: if the intake grille is not completely closed, the unit will not operate and the lamps blink this way (RLS2 Operation Manual, p. En-20). The RLS2 service manual table has no 58 (RLS2 Service Manual, p. 11); the service instructions have a check section (RLS2 Service Instructions, p. 02-11).		RLS2Owner checks, then technicianRLS2 service instr. p. 02-01; RLS2 owner's p. En-20
59“Indoor unit fan motor 2 error (Left side fan)”
OPERATION 5 / TIMER 9. Installation manual lists only. The KPBS list says “(Lower fan)” (KPBS Installation Manual, p. En-16).		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLF1 install p. En-13
5A“Indoor unit fan motor 3 error (Right side fan)”
OPERATION 5 / TIMER 10 (A = 10 blinks). Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLF1 install p. En-13
5U“Indoor unit error”
OPERATION 5 / TIMER 15 (U = 15 blinks). The KPAS/KPBS service manual's only check is “Check following error code.” (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-44). Not in the KNAS, KTAS, ASLH or L service manual tables. The RLB service manual table, marked “under confirmation”, prints dashes instead of blink counts (RLB Service Manual, p. 7).		KPAS, KPBS, KMAS, KZAS, RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianKPAS/KPBS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; RLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
61“Outdoor unit reverse/missing phase and wiring error”
OPERATION 6 / TIMER 1. Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLS3Y install p. En-12; RLF1 install p. En-13
62“Outdoor unit main PCB error (Outdoor unit)”
OPERATION 6 / TIMER 2. KNAS: “Outdoor unit Main PCB communication error” (KNAS Service Manual SR_AS159ES_02, p. 03-2). KPAS installation manual: “Outdoor unit main PCB model information error or communication error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
62“Outdoor unit main PCB model information error or communication error”
OPERATION 6 / TIMER 2. RLS3 service instructions: “Outdoor Unit Main PCB Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
63“Inverter error (Outdoor unit)”
OPERATION 6 / TIMER 3. KNAS prints it without “(Outdoor unit)”. Not in the KPAS/KPBS, KMAS, LMAS or LPAS service manual tables, although the KPAS installation manual lists “Inverter error” (KPAS Installation Manual, p. En-16).		KNAS, KZAS, KTAS, ASLH, LZBS, LZASTechnicianKNAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2
63“Inverter error”
OPERATION 6 / TIMER 3. The RLS3Y service instruction has a check section for it (RLS3Y Service Instruction, pp. 02-16–02-17).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
64“PFC circuit error (Outdoor unit)”
OPERATION 6 / TIMER 4. KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “Active filter error, PFC circuit error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
64“Active filter error, PFC circuit error”
OPERATION 6 / TIMER 4. RLS3 service instructions: “PFC Circuit Error (9/12RLS3) / Active Filter Error (15RLS3)” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
65“IPM error (Outdoor unit)”
OPERATION 6 / TIMER 5. KZAS adds a second 65 line, “Trip terminal L error (Outdoor unit)” (KZAS Service Manual SR_AS137ES_03, p. 03-2). KNAS prints it without “(Outdoor unit)”. Not in the LMAS table. KPAS installation manual: “• Trip terminal L error • IPM temp error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-2; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LPAS service p. 03-2
65“Trip terminal L error”
OPERATION 6 / TIMER 5. RLS3 service instructions: “IPM Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-11; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
68“Outdoor unit rush current limiting resister temp. rise error”
OPERATION 6 / TIMER 8. Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLF1 install p. En-13
6A“Display PCB microcomputers communication error”
OPERATION 6 / TIMER 10 (A = 10 blinks). Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table. The RLB service manual table, marked “under confirmation”, says “Display panel error” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
71“Discharge thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 1. KNAS gives 71, 72, 73 and 74 one name, “Outdoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-3, 03-48). KPAS installation manual: “Discharge temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
71“Discharge temp. sensor error”
OPERATION 7 / TIMER 1. RLS3 service instructions: “Discharge Thermistor Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
72“Compressor thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 2. KNAS: “Outdoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-3, 03-48). Not in the KMAS, ASLH, LMAS or LPAS tables. KPAS installation manual: “Compressor temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KZAS, KTAS, LZBS, LZASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-3; KZAS service p. 03-2; KTAS service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2
72“Compressor temp. sensor error”
OPERATION 7 / TIMER 2.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
73“Outdoor unit heat exchanger liquid outlet thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 3. KNAS: “Outdoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-3, 03-48). KPAS installation manual: “Outdoor unit Heat Ex. liquid temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-2
73“Outdoor unit heat exchanger thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 3. The KPAS/KPBS, KMAS and KZAS tables call the same code a “liquid outlet thermistor” error (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-2).		KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
73“Outdoor unit Heat Ex. liquid temp. sensor error”
OPERATION 7 / TIMER 3. RLS3 service instructions: “Heat Ex. (Pipe) Thermistor Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
74“Outdoor temperature thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 4. KNAS: “Outdoor unit thermistor error”; its check section names the thermistor for each code (KNAS Service Manual SR_AS159ES_02, pp. 03-3, 03-48). KPAS installation manual: “Outdoor temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
74“Outdoor temp. sensor error”
OPERATION 7 / TIMER 4. RLS3 service instructions: “Outdoor Thermistor Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
75“Suction Gas temp. sensor error”
OPERATION 7 / TIMER 5. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
76“• 2-way valve temp. sensor error • 3-way valve temp. sensor error”
OPERATION 7 / TIMER 6. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11). No K or L service manual table gives it a blink row; KNAS names 76 only in a combined heading with 71–74 and 77 (KNAS Service Manual SR_AS159ES_02, p. 03-3).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
77“Heat sink thermistor error (Outdoor unit)”
OPERATION 7 / TIMER 7. Not in the other K or L service manual tables. KPAS installation manual: “Heat sink temp. sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-2
77“Heat sink temp. sensor error”
OPERATION 7 / TIMER 7.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
82“• Sub-cool Heat Ex. gas inlet temp. sensor error • Sub-cool Heat Ex. gas outlet temp. sensor error”
OPERATION 8 / TIMER 2. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
83“Liquid pipe temp. sensor error”
OPERATION 8 / TIMER 3. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
84“Current sensor error (Outdoor unit)”
OPERATION 8 / TIMER 4. KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “Current sensor error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-2; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
84“Current sensor error”
OPERATION 8 / TIMER 4.		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
86“High pressure switch error (Outdoor unit)”
OPERATION 8 / TIMER 6. The same table has a second 86 line, “Pressure sensor error (Outdoor unit)”. Not in the other K or L service manual tables. KPAS installation manual: “• Discharge pressure sensor error • Suction pressure sensor error • High pressure switch error” (KPAS Installation Manual, p. En-16).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-3
86“Pressure sensor error (Outdoor unit)”
OPERATION 8 / TIMER 6, the same blinks as the high pressure switch error (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-3).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-3
86“• Discharge pressure sensor error • Suction pressure sensor error • High pressure switch error”
OPERATION 8 / TIMER 6.		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
94“Over current error (Outdoor unit)”
What to check
OPERATION 9 / TIMER 4. Set when the compressor makes 10 overcurrent protection stops in a row after its start-up has finished (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-58). KZAS also has a “Trip detection (Outdoor unit)” line for 94 (see the next row). KPAS installation manual: “Trip detection” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KMAS, KZASTechnicianKPAS/KPBS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-2
94“Trip detection (Outdoor unit)”
What to check
OPERATION 9 / TIMER 4. KNAS prints it without “(Outdoor unit)”. In the KZAS manual the inverter PCB detects this line and the main PCB detects the over current line (KZAS Service Manual SR_AS137ES_03, pp. 03-54–03-55).		KNAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKNAS service p. 03-3; KZAS service p. 03-2; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
94“Trip detection”
What to check
OPERATION 9 / TIMER 4. RLS3 service instructions: “Over Current Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
95“Compressor motor control error (Outdoor unit)”
OPERATION 9 / TIMER 5. KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “Compressor rotor position detection error (permanent stop)” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-3; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-3; KTAS service p. 03-2; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
95“Compressor rotor position detection error (permanent stop)”
OPERATION 9 / TIMER 5. RLS3Y, RLB and RL2 print it without “(permanent stop)” (RLS3Y Service Manual, p. 7; RLB Installation Manual, p. En-12; RL2 Service Manual, p. 12). RLS3 service instructions: “Compressor Control Error” (RLS3 Service Instructions, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
97“Outdoor unit fan motor error (Outdoor unit)”
What to check
OPERATION 9 / TIMER 7. The outdoor fan is stopped when it runs below 100 rpm 20 seconds after starting; repeated stops shut the compressor and fan down (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-60). KNAS heads it “97 / 98.X. Outdoor unit fan motor error” (KNAS Service Manual SR_AS159ES_02, p. 03-3). KPAS installation manual: “Outdoor unit fan motor 1 error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-3; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-3; KTAS service p. 03-3; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
97“Outdoor unit fan motor error”
What to check
OPERATION 9 / TIMER 7. The RLS3Y installation manual says “Outdoor unit fan motor 1 error” (RLS3Y Installation Manual, p. En-12).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
98“Outdoor unit fan motor 2 error”
OPERATION 9 / TIMER 8. Installation manual lists only. The KNAS service manual names 98 together with 97 in one heading, without a blink row of its own (KNAS Service Manual SR_AS159ES_02, p. 03-3).		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLS3Y install p. En-12; RLF1 install p. En-13
99“4-way valve error (Outdoor unit)”
OPERATION 9 / TIMER 9. KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “4-way valve error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-3; KNAS service p. 03-3; KMAS service p. 03-2; KZAS service p. 03-3; KTAS service p. 03-3; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
99“4-way valve error”
OPERATION 9 / TIMER 9.		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
9A“Coil (expansion valve) error”
OPERATION 9 / TIMER 10 (A = 10 blinks). Installation manual lists only; no service manual table used here has it.		Installation manual listsTechnicianKPAS install p. En-16; LZBS install p. En-11; RLS3Y install p. En-12; RLF1 install p. En-13
A1“Discharge temperature error (Outdoor unit)”
What to check
OPERATION 10 / TIMER 1 (A = 10 blinks). Set when the compressor makes a protection stop at a discharge temperature of 230°F (110°C) or more twice within 24 hours (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-64). KNAS prints it without “(Outdoor unit)”. KPAS installation manual: “Discharge temp. error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH, LZBS, LZAS, LMAS, LPASTechnicianKPAS/KPBS service p. 03-3; KNAS service p. 03-3; KMAS service p. 03-3; KZAS service p. 03-3; KTAS service p. 03-3; ASLH service p. 03-2; LZBS service p. 03-2; LZAS service p. 03-2; LMAS service p. 03-2; LPAS service p. 03-2
A1“Discharge temp. error”
What to check
OPERATION 10 / TIMER 1. The RLS3 service instructions print the same 230°F (110°C), twice-in-24-hours rule (RLS3 Service Instructions, p. 02-24).		RLS3, RLS3Y, RLB, RLS2, RLF1, RL2TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14; RL2 service p. 12
A3“Compressor temperature error (Outdoor unit)”
What to check
OPERATION 10 / TIMER 3 (A = 10 blinks). Set when the compressor makes a protection stop at a compressor temperature of 226°F (108°C) or more twice within 24 hours (KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-66). Not in the KMAS, ASLH, LMAS or LPAS tables. KPAS installation manual: “Compressor temp. error” (KPAS Installation Manual, p. En-16).		KPAS, KPBS, KNAS, KZAS, KTAS, LZBS, LZASTechnicianKPAS/KPBS service p. 03-3; KNAS service p. 03-3; KZAS service p. 03-3; KTAS service p. 03-3; LZBS service p. 03-2; LZAS service p. 03-2
A3“Compressor temp. error”
What to check
OPERATION 10 / TIMER 3. These service manual tables have no check section, and the service instructions for these lines do not cover A3 (RLS3 Service Instructions, p. 02-01; RLS3Y Service Instruction, p. 02-01; RLB Service Instructions, p. 02-01; RLS2 Service Instructions, p. 02-01; RLFW1 Service Instruction, p. 02-01).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
A4“High pressure error”
OPERATION 10 / TIMER 4. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-11), but in no K or L service manual table. The RLB service manual table, marked “under confirmation”, says “Pressure error 1” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
A5“Low pressure error”
OPERATION 10 / TIMER 5. Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-12), but in no K or L service manual table. The RLB service manual table, marked “under confirmation”, says “Pressure error 2” (RLB Service Manual, p. 7).		RLS3, RLS3Y, RLB, RLS2, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLS2 service p. 11; RLF1 service p. 14
A8“Refrigerant leak detection”
OPERATION 10 / TIMER 8. Printed only in the KPBS installation manual list; the KPAS/KPBS service manual table has no A8 (KPAS/KPBS Service Manual SR_AS142ES_09, pp. 03-2–03-3). If a refrigerant leak is suspected, the KPBS owner's manual says to remove or put out open flames and consult authorized service personnel (KPBS Operation Manual, p. En-2).		Installation manual listsTechnicianKPBS install p. En-16
AC“Heat sink temperature error (Outdoor unit)”
OPERATION 10 / TIMER 11 (A = 10, C = 11 blinks). Not in the other K or L service manual tables. KPAS installation manual: “Heat sink temp error” (KPAS Installation Manual, p. En-16).		KPAS, KPBSTechnicianKPAS/KPBS service p. 03-3
J2“Branch boxes error”
OPERATION 13 / TIMER 2 (J = 13 blinks). RLS3Y: “Branch boxes error [flexible multi]” (RLS3Y Service Manual, p. 7); RLB: “Branch boxes error[Flexible Multi]” (RLB Installation Manual, p. En-12). Also in the KPAS and LZBS installation manual lists (KPAS Installation Manual, p. En-16; LZBS Installation Manual, p. En-12), but in no K or L service manual table.		RLS3, RLS3Y, RLB, RLF1TechnicianRLS3 service p. 7; RLS3Y service p. 7; RLB install p. En-12; RLF1 service p. 14
J7“External device error”
OPERATION 13 / TIMER 7 (J = 13 blinks). Printed only in the KPBS installation manual list; the KPAS/KPBS service manual table has no J7 (KPAS/KPBS Service Manual SR_AS142ES_09, pp. 03-2–03-3).		Installation manual listsTechnicianKPBS install p. En-16

How to read a Fujitsu code

A Fujitsu wall unit shows a fault on its indoor lamps. OPERATION blinks the first character of the code and TIMER blinks the second, each blink 0.5 second on and 0.5 second off, while ECONOMY blinks fast (0.1 second on, 0.1 second off) the whole time. Two OPERATION blinks and four TIMER blinks are code 24 KPAS Installation Manual, p. En-16; KNAS Installation Manual, p. En-19. The KPAS installation manual prints OPERATION as green, TIMER as orange and ECONOMY as green, and says the code shows only while the unit is operating; a wired remote controller shows it on its display KPAS Installation Manual, p. En-16. On RLS3 units “Er” appears in the wired remote’s set room temperature display RLS3 Installation Manual, p. En-12.

Several owner’s manuals add a Service check mode on the wireless remote: you hold a button for more than 5 seconds and step through the codes; the indoor unit beeps several times and blinks all its lamps at the matching code, and multiple beeps at “00” mean no error was detected KPAS Operation Manual, pp. En-13–En-14; KNAS Operation Manual, p. En-11; KZAS Operation Manual, p. En-16; KTAS Operation Manual, p. En-15; ASLH Operation Manual, p. En-11; LPAS Operation Manual, p. En-13. The KPBS remote can add a third digit, as in 11.1 KPBS Operation Manual, p. En-12. The KMAS, LZBS, LZAS, LMAS and RLS3-era owner’s manuals describe no such mode; for those units the blinks are looked up in the lamp table of the installation or service manual LZBS Installation Manual, p. En-11; RLS3 Installation Manual, pp. En-11–En-12; RL2 Service Manual, p. 12.

For each code, the table gives the K series (R-32) and L series (R-410A) first, quoted from their service manuals, then the RLS3-era lines (RLS3, RLS3Y, RLB, RLS2, RLF1, RL2); wording that differs by series is in the row’s note. The K and L installation manuals print longer lists, and a code found only there is marked “Installation manual lists”. Such a code is not proof that your unit can show it: the KPAS list says “Unnecessary error codes for this product may be included in the list.” KPAS Installation Manual, p. En-16. The ASLH, RLS2 and RL2 tables print blink counts without a code column, so their codes here are read from the counts ASLH Service Manual SR_AS143ES_03, p. 03-2; RLS2 Service Manual, p. 11; RL2 Service Manual, p. 12. RLB meanings come from its installation manual, because the RLB service manual’s table is marked “under confirmation” RLB Service Manual, p. 7.

Older units read blinks differently: in Fujitsu’s 2010–2011 troubleshooting guide for lines such as RLQ and CL, two OPERATION and two TIMER blinks are code 02, “Room temperature thermistor error” High-SEER R410A Mini-Splits Troubleshooting Guide 2010-2011, p. 2. Use the manual for your model. Ducted and cassette units and the RLF Hybrid Flex system are not in this table. In the ARUH-L ducted manual AC is 10 OPERATION and 12 TIMER blinks, where KPAS and KPBS wall units use 10 and 11 ARUH-L Service Manual SR_AR056EF_02, p. 03-3; KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-3; the Hybrid Flex manual reads 2 and 1 blinks as “Number of Wires and Pipes Error” Hybrid Flex RLF Service Manual, p. 49.

Ten blinks stand for the letter A. Ten OPERATION blinks and one TIMER blink are A1, a discharge temperature error; ten and three are A3, a compressor temperature error KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-3. Ten TIMER blinks put the A second, as in 3A, 5A, 6A and 9A. C is 11 blinks, J is 13 and U is 15, so AC is 10 and 11 blinks and 5U is 5 and 15 KPAS Installation Manual, p. En-16. Service check, where your remote has it, shows the code as characters KPAS Operation Manual, pp. En-13–En-14.

What the owner’s manuals call normal

The owner’s manual’s lamp table lists these states apart from the error code display KPAS Operation Manual, p. En-13:

  • OPERATION blinking in heating is automatic defrosting; the indoor unit stops for a maximum of 15 minutes KPAS Operation Manual, p. En-12; RLS3 Operation Manual, p. En-10. The RLB manual says “maximum of 15 minutes” on one page and “between 7 and 15 minutes” on another RLB Operation Manual, pp. En-6, En-8.
  • TIMER blinking after a power cut is a timer setting error caused by the auto restart. Reset the clock and timer settings KPAS Operation Manual, p. En-9.
  • ECONOMY blinking 3 times is the filter indicator: clean the filter and reset the sign. The RLF1 manual times it at 3 blinks every 21 seconds RLF1 Operation Manual, p. En-7.
  • OPERATION and TIMER blinking together can be a test run, which is for authorized personnel; the remote’s on/off button ends it.

After the power supply goes off and on, the compressor does not run for about 3 minutes, to prevent a blown fuse KPAS Operation Manual, p. En-12; RLS3 Operation Manual, p. En-10.

Clearing a code

The owner’s manuals give no reset for an error code. When OPERATION and TIMER blink while ECONOMY blinks fast, they say: “Immediately stop operation and turn off the electrical breaker in following cases. Then consult authorized service personnel.” RLS3 Operation Manual, p. En-10; KPAS Operation Manual, p. En-12. For everyday use the KPAS manual says not to start or stop the unit with the circuit breaker or the power plug KPAS Operation Manual, p. En-2, and the RLS3 manual says not to do it by disconnecting the power supply cord RLS3 Operation Manual, p. En-1.

The manuals mention switching the breaker off and on in two other cases: a malfunction caused by other electrical devices, such as an electric shaver or a nearby radio transmitter, and a wireless LAN adapter that is not connected to the access point KPAS Operation Manual, pp. En-9, En-13. Neither is given as a way to clear a code. Erasing the stored error is described in the installation and service manuals KPAS Installation Manual, p. En-16; KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-1.

One owner’s manual ties a lamp pattern to something you can fix. On RLS2 units, if the intake grille is not completely closed, the unit will not run, OPERATION blinks 5 times, TIMER 8 times, and ECONOMY keeps blinking RLS2 Operation Manual, p. En-20. The RLS2 service instructions list that pattern as code 58 RLS2 Service Instructions, p. 02-01.

When to stop and call a professional

For a malfunction such as a burning smell, stop the unit, disconnect the power at the breaker or the plug, and consult authorized service personnel KPAS Operation Manual, p. En-1. If you suspect a refrigerant leak, the KPAS manual says to remove or put out any open flame and consult authorized service personnel, and warns that refrigerants may have no odor; its symbol list says the unit uses a low burning velocity material, with a risk of fire if leaked refrigerant meets an ignition source KPAS Operation Manual, p. En-1. Every owner’s manual used here says the unit has no user-serviceable parts KPAS Operation Manual, p. En-1; RLS3 Operation Manual, p. En-1. Refrigerant work is for a technician certified under EPA Section 608. The warning box on each code page quotes the KPAS manual; the RLS3 manual has similar warnings RLS3 Operation Manual, p. En-1.

See also

Other ductless mini-splits: Daikin, Mitsubishi Electric, MrCool

Fujitsu is a trademark of its owner. How House Works is not affiliated with or endorsed by Fujitsu.

Sources

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