Fujitsu · Heat pump

27 Primary / secondary unit setup error

Medium severity Fujitsu ductless split/multi/VRF (general code list)Fujitsu wall-mounted 7-15 (NA ASU/AOU type)Fujitsu slim duct ARU 7-18 (LL type)

What the control is telling you

Master (primary) and slave (secondary) unit roles are set wrong in a simultaneous multi system. Indoor lamps: OPERATION (green) flashes 2x, TIMER (orange) flashes 7x, ECONOMY (green) flashes fast nonstop; wired remote shows 27.

Applies to: Fujitsu ductless heat pumps: Fujitsu ductless split/multi/VRF (general code list), Fujitsu wall-mounted 7-15 (NA ASU/AOU type), Fujitsu slim duct ARU 7-18 (LL type)

Likely causes

Primary/secondary DIP or function setting wrong

Test and repair steps

Set exactly one primary unit and the rest as secondary per the install manual.
Cycle power.

Settings for these units

Operating range and service space · Fujitsu multi-zone outdoor 18/24 type

Other codes on the same units

22 Indoor unit capacity error
23 Combination error
24 Connection unit number error
26 Indoor unit address setting error
29 Connection unit number error (wired remote system)
31 Power supply interruption error
32 Indoor main PCB error (EEPROM / model info)
33 Indoor fan motor power consumption error

Save it for the next call

Star this code in the HVACopedia app and keep the whole library on your phone for jobs with no signal.

Open the app

Source: Fujitsu All Fujitsu split - multi - VRF (generic code list) codes.pdf - section error code table (indoor LED flashes); Fujitsu Wall-mounted 7-9-12-15 (North American trilingual, UTY-RNNUM remotes; e.g. ASU9-12-15 RLF1-RLS familie.pdf - section 14 Error codes; Fujitsu Slim duct AR07-09-12-14-18 (ARU-ARYG LL-type equivalent) installation P-N 9381858064.pdf - section 14 Error codes. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.