Overview

This document outlines the factory and configurable DIP switch settings for both the indoor and outdoor units of Fujitsu LUAK and LJBYL series systems. These settings govern key operational parameters such as temperature correction, auto restart, mode selection, and fan speed configuration.


1. Indoor Unit DIP Switch Settings

SW1 (Factory Reserved)

Switch No.OFFONDescription
1–4Out of use / Factory default

Note: SW1 switches are not used for field adjustment.


SW2 (Indoor Unit Functional Adjustments)

Switch No.OFFONFunction
1+4 °C0 °CRoom temperature correction (heating)
2EdgePulseControl input signal setting
3ValidityInvalidityAuto restart function enable/disable

Field Guidance:

  • Use SW2-1 for minor calibration of heating temperature offset (+4 °C correction available).

  • SW2-2 determines input method for external control (Edge/Pulse).

  • SW2-3 enables the Auto Restart function after power failure when set to OFF (Validity).


Jumper Wire Settings (JM1–JM3)

JumperConnectedDisconnectedFunction
JM10 °C+2 °CRoom temp correction (cooling)
JM2ResidentialCommercialSelects commercial mode operation
JM3NormalHeater settingEnables heater mode operation

Field Tip:

  • Adjust JM1 to +2 °C if occupants report overcooling under typical ambient conditions.

  • Set JM2 to “Commercial” when integrating with BMS or third-party control systems.


2. Remote Control DIP and Jumper Settings

Switch / JumperOFFONDescription
SW1-1Dual remote controller mode
SW1-3One UnitMultiple UnitGroup control configuration
SW1-4Heat & CoolCooling OnlyModel type selection
SW1-5InvalidityValidityAuto changeover activation
SW1-6InvalidityValidityMemory backup enablement
J5 (Fan Speed)3-speed (HI, MED, LO)1-speed (HI)Fan speed mode (AR90 only)

Factory default: Single unit, heat & cool model, 3-speed fan operation.


3. Outdoor Unit DIP Switch Configuration

Used primarily for setting maximum current capacity and thermal protection calibration.

DIP No.123Max Current (A)Model Reference
OFF OFF OFF17.5 A36,000 BTU (factory)
ON OFF OFF15.0 A30,000 BTU (factory)
OFF ON OFF13.0 AReduced performance mode
ON ON OFF10.5 ALow power protection mode

⚠️ Caution:

  • Do not set a 30,000 BTU model to 17.5 A — this may disable protection devices and prevent operation.

  • Reducing the current limit below the factory value will decrease cooling and heating performance.


4. Field Implementation Notes

  • Always power down the system before changing DIP or jumper settings.

  • Record all modifications on the commissioning sheet for traceability.

  • If settings are incorrect, unit may display fault codes relating to mode conflict or sensor calibration error.

  • Ensure both indoor and outdoor settings correspond to the unit’s rated model (LUAK or LJBYL).