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Fujitsu code 22: indoor unit capacity error

By How House Works EditorialBased on Fujitsu manualsChecked against sources Updated

Fujitsu display

22

“Indoor unit capacity error (Indoor unit)”

KPAS, KPBS, KNAS, KMAS, KZAS, KTAS, ASLH · KPAS/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
Technician

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.

What it means

Code 22 is an indoor unit capacity error. In the installation manuals’ lamp tables it is two OPERATION blinks and two TIMER blinks, repeated, while ECONOMY blinks fast KPAS Installation Manual, p. En-16; RLS3 Installation Manual, p. En-11.

In the KPAS/KPBS service manual the indoor unit’s main PCB sets it “When the total capacity of the indoor units does not match outdoor unit capacity while 3 minutes after power on.” The causes listed are an incorrect selection of indoor units and a failed main PCB KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-30. In that manual’s mobile app table the code is 22.1, “Indoor unit capacity error” KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-8. The manual does not say when such a mismatch arises.

Check these first

Fujitsu’s owner’s manuals give no owner fix for this code. The steps are the same as for any code; the manuals’ wording is on the code 11 page.

  1. Check that it is an error code: OPERATION and TIMER blink while ECONOMY blinks fast KPAS Operation Manual, p. En-13.
  2. Read the code with Service check if your remote has it KPAS Operation Manual, pp. En-13–En-14.
  3. Stop the unit, turn off its breaker and consult authorized service personnel, as the manuals require for this lamp pattern RLS3 Operation Manual, p. En-10; KPAS Operation Manual, p. En-12. This is separate from their rule against using the breaker for everyday on and off KPAS Operation Manual, p. En-2.
  4. Give them the code KPAS Operation Manual, p. En-14.

When to call a licensed technician

The service manual has two checks for 22, both for the technician KPAS/KPBS Service Manual SR_AS142ES_09, p. 03-30:

  • Check the total capacity of the indoor units. If something is wrong, correct it using the installation manual or the Design & Technical Manual.
  • If that does not improve the symptom, replace the main PCB.

The installation manual says installation must be done only by experienced service technicians or professional installers, in accordance with that manual KPAS Installation Manual, p. En-2. For work on electrical parts, Fujitsu sets a waiting time after power-off: 5 minutes in the service manual, 10 minutes in the KPAS installation manual KPAS/KPBS Service Manual SR_AS142ES_09, p. 02-1; KPAS Installation Manual, p. En-2.

Notes for different models

  • The other K-series service manuals have their own sections for 22 KNAS Service Manual SR_AS159ES_02, p. 03-31; KMAS Service Manual SR_AS134ES_03, p. 03-28; KZAS Service Manual SR_AS137ES_03, p. 03-28; KTAS Service Manual SR_AS147ES_04, p. 03-29; ASLH Service Manual SR_AS143ES_03, p. 03-25. KNAS drops the “(Indoor unit)” tag KNAS Service Manual SR_AS159ES_02, p. 03-2.
  • The L-series service manual tables have no 22 LZBS Service Manual SR_AS048EF_02, p. 03-2; LZAS Service Manual SR_AS024EF_09, p. 03-2; LMAS Service Manual SR_AS058EF_04, p. 03-2; LPAS Service Manual SR_AS050EF_03, p. 03-2, although the LZBS installation manual lists it LZBS Installation Manual, p. En-11.
  • RLS3-era tables list 22 as “Indoor unit capacity error” with no check section RLS3 Service Manual, p. 7, and their service instructions do not cover it 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.
  • On older units in Fujitsu’s 2010–2011 troubleshooting guide, two OPERATION and two TIMER blinks mean code 02, “Room temperature thermistor error” High-SEER R410A Mini-Splits Troubleshooting Guide 2010-2011, p. 2.

Related Fujitsu codes

  • 23 “Combination error (Outdoor unit)”
  • 29 “Connected unit number error (Indoor unit)”

See also

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

All Fujitsu codes

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

Sources

  1. GENERAL Inc.. KPAS/KPBS Service Manual SR_AS142ES_09. Document code SR_AS142ES_09, page stamp 2026.06.18; covers ASUH09–36KPAS/KPBS and AOUH09–36KPAS1. The 2026 revision. It adds code 45, which the earlier revision SR_AS142ES_04 does not list.. Accessed Oct 12, 2026.
  2. Fujitsu General America / GENERAL HVAC Solutions America (document portal). KPAS Installation Manual. PART No. 9387603408-01; KP series; no publication date printed. Accessed Oct 12, 2026.
  3. Fujitsu General America / GENERAL HVAC Solutions America (document portal). KPAS Operation Manual. PART No. 9387602548-01; KP series; no publication date printed. Accessed Oct 12, 2026.
  4. Fujitsu General Limited. KNAS Service Manual SR_AS159ES_02. Document code SR_AS159ES_02, page stamp 2025.10.08; covers ASUH09–24KNAS and AOUH09–24KNAS1. Accessed Oct 12, 2026.
  5. Fujitsu General Limited. KMAS Service Manual SR_AS134ES_03. Document code SR_AS134ES_03, page stamp 2024.11.11; covers ASUH09/12KMAS and AOUH09/12KMAS1. Accessed Oct 12, 2026.
  6. Fujitsu General Limited. KZAS Service Manual SR_AS137ES_03. Document code SR_AS137ES_03, page stamp 2025.01.09; covers ASUH09–24KZAS and AOUH09–24KZAH1. Accessed Oct 12, 2026.
  7. Fujitsu General Limited. KTAS Service Manual SR_AS147ES_04. Document code SR_AS147ES_04, page stamp 2025.07.30; titled Service Manual for Cold Climate Region; covers ASUH09/12/15KTAS and KTAB with AOUH09/12/15KTAP1. Accessed Oct 12, 2026.
  8. Fujitsu General Limited. ASLH Service Manual SR_AS143ES_03. Document code SR_AS143ES_03, page stamp 2024.11.11; covers ASLH09/12KNAS and AOLH09/12KNAS1, 115 V. Its code table prints blink counts only, with no wired remote controller code column.. Accessed Oct 12, 2026.
  9. Fujitsu General Limited. LZBS Service Manual SR_AS048EF_02. Document code SR_AS048EF_02, page stamp 2022.10.14; covers ASUG09–15LZBS and AOUG09–15LZAS1. Accessed Oct 12, 2026.
  10. Fujitsu General America / GENERAL HVAC Solutions America (document portal). LZBS Installation Manual. PART No. 9387603187; no publication date printed. Accessed Oct 12, 2026.
  11. Fujitsu General Limited. LZAS Service Manual SR_AS024EF_09. Document code SR_AS024EF_09, page stamp 2022.10.12; covers ASUG09–15LZAS and AOUG09–15LZAS1. Accessed Oct 12, 2026.
  12. Fujitsu General Limited. LMAS Service Manual SR_AS058EF_04. Document code SR_AS058EF_04, page stamp 2022.10.05; covers ASUH09/12LMAS and AOUH09/12LMAS1. Accessed Oct 12, 2026.
  13. Fujitsu General Limited. LPAS Service Manual SR_AS050EF_03. Document code SR_AS050EF_03, page stamp 2022.10.18; covers ASUH09/12LPAS and AOUH09/12LPAS1. Accessed Oct 12, 2026.
  14. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS3 Service Manual. No document code printed; the error table page is stamped 2015.01.06; covers ASU9/12RLS3 and AOU9/12RLS3. Accessed Oct 12, 2026.
  15. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS3 Service Instructions. No document code or date printed; covers ASU9/12/15RLS3 and AOU9/12/15RLS3. Accessed Oct 12, 2026.
  16. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS3 Installation Manual. PART No. 9320456016; no publication date printed. Accessed Oct 12, 2026.
  17. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS3 Operation Manual. PART No. 9320455026; no publication date printed. Accessed Oct 12, 2026.
  18. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS3Y Service Instruction. No document code or date printed; covers ASU9/12/15RLS3Y and AOU9/12/15RLS3. The cover is stamped “TENTATIVE”.. Accessed Oct 12, 2026.
  19. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLB Service Instructions. No document code or date printed; covers ASU18/24RLB and AOU18/24RLB. Accessed Oct 12, 2026.
  20. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLS2 Service Instructions. No document code or date printed; covers ASU9/12/15RLS2 and AOU9/12/15RLS2. Accessed Oct 12, 2026.
  21. Fujitsu General America / GENERAL HVAC Solutions America (document portal). RLFW1 Service Instruction. No document code or date printed; covers ASU9/12RLF1 and AOU9/12RLFW1. Accessed Oct 12, 2026.
  22. Fujitsu General America, Inc.. High-SEER R410A Mini-Splits Troubleshooting Guide 2010-2011. Revision 10/10, Part #6-26-FG2020; no page numbers printed, page references are PDF pages. Covers older lines such as ASU9/12/15/18RLQ, ASU24CL and ASU30CLX. Used here only to show that older units read blinks differently; not used for the table.. Accessed Oct 12, 2026.