Fujitsu Airstage Service Manual

The Fujitsu Airstage is a comprehensive HVAC system featuring advanced air conditioning technology, energy-efficient operation, intelligent climate control, multi-zone capabilities, remote monitoring, and maintenance diagnostics. Designed for commercial and residential applications with various models including split systems, VRF systems, and central air conditioning units. Below are key sections for safety procedures, technical specifications, installation guidelines, maintenance protocols, troubleshooting, and repair procedures.

1. System Overview 2. Safety Precautions 3. Technical Specifications 4. Installation Procedures 5. Electrical Connections 6. Refrigerant Handling 7. Maintenance Schedule 8. Diagnostic Codes 9. Troubleshooting Guide 10. Parts Replacement 11. Warranty Information

System Overview

Key components: Outdoor unit, Indoor units, Remote controller, Refrigerant piping, Electrical connections, Communication cables.

ComponentDescription
Outdoor UnitCompressor, condenser, fan motor, control board
Indoor UnitEvaporator, blower motor, air filter, drain pan
Remote ControllerTemperature setting, mode selection, timer functions
Refrigerant PipingCopper pipes for refrigerant flow between units
Electrical ConnectionsPower supply, communication wiring, safety switches
Control BoardMain processor, memory, input/output interfaces
Temperature SensorsRoom temperature, coil temperature, ambient temperature
Expansion ValveElectronic expansion valve for refrigerant control
Fan MotorsDC inverter motors for efficient airflow
Drain SystemCondensate removal piping and pump

Safety Precautions

Always follow safety protocols when servicing HVAC equipment.

  1. Electrical Safety: Disconnect power before servicing; use lockout/tagout procedures.
  2. Refrigerant Safety: Wear protective gloves and goggles when handling refrigerants.
  3. Working at Height: Use proper fall protection when installing outdoor units.
  4. Lifting Safety: Use appropriate equipment for heavy component handling.

WARNING! High voltage present in electrical components. Refrigerant under high pressure. Always follow local codes and regulations.

Technical Specifications

Installation Procedures

Proper installation is critical for system performance and longevity.

  1. Site Selection: Choose location with adequate clearance and proper drainage.
  2. Unit Mounting: Secure outdoor unit on level pad or brackets; mount indoor unit per instructions.
  3. Piping Installation: Cut and flare copper pipes; ensure no debris enters system.
  4. Vacuum Dehydration: Evacuate system to 500 microns minimum before releasing refrigerant.
  5. Electrical Wiring: Connect power and communication cables according to wiring diagram.
  6. System Check: Test operation in cooling and heating modes; verify proper drainage.

CAUTION! Ensure all connections are tight and properly insulated. Follow torque specifications for flare nuts.

Electrical Connections

Electrical specifications and connection procedures for various models.

TerminalFunctionSpecification
L1, L2Power Input208-230V AC
NNeutralWhite wire
GGroundGreen or bare copper
S1, S2CommunicationTwo-wire communication bus
YCompressor ControlCompressor speed signal
CCommonCommon return

Tip: Always verify voltage and phase requirements before connecting power.

Refrigerant Handling

Proper procedures for refrigerant charging and recovery.

  1. System Evacuation: Connect vacuum pump to service ports; evacuate to 500 microns.
  2. Leak Testing: Pressurize with dry nitrogen to 150 psi; check all connections with electronic leak detector.
  3. Charging: Add refrigerant in liquid form to high side with system off, or vapor form to low side with system running.
  4. Weighing Charge: Use scale to measure exact refrigerant amount per nameplate specification.
  5. Recovery: Use approved recovery machine; never vent refrigerant to atmosphere.

WARNING! R410A operates at higher pressures than R22. Use dedicated R410A gauges and hoses.

Maintenance Schedule

Regular maintenance ensures optimal performance and extends system life.

IntervalTaskProcedure
MonthlyFilter CleaningWash or replace air filters
SeasonalCoil InspectionClean evaporator and condenser coils
AnnualElectrical CheckInspect connections, measure voltage/amperage
AnnualRefrigerant CheckMeasure superheat and subcooling
BiannualDrain SystemClear condensate drain lines
As NeededFan MaintenanceClean blower wheels, check motor bearings

Diagnostic Codes

Common error codes and their meanings for troubleshooting.

CodeDescriptionPossible Cause
E0Protection Device ActivatedHigh pressure, overload, temperature sensor
E1PCB ErrorControl board malfunction
E3High Pressure ProtectionDirty condenser, fan failure, overcharge
E4Low Pressure ProtectionRefrigerant leak, restriction, undercharge
E5Compressor OverloadElectrical issue, mechanical failure
E6Communication ErrorWiring issue, board failure
E7Outdoor Fan Motor ErrorMotor failure, capacitor, wiring
E8AC Input OvercurrentPower supply issue, short circuit
E9Cold Storage ProtectionLow ambient temperature operation

Troubleshooting Guide

SymptomPossible CauseCorrective Action
Unit not startingPower supply, fuse, breakerCheck voltage, reset breaker, replace fuse
Poor cooling/heatingDirty filters, low refrigerantClean filters, check charge, clean coils
Unusual noisesLoose parts, fan imbalanceTighten fasteners, balance fan assembly
Water leakageClogged drain, improper slopeClear drain line, ensure proper pitch
Error code displayedSystem faultRefer to diagnostic code chart
Short cyclingThermostat, pressure switchCheck thermostat location, pressure settings

Reset Procedure: Turn power off for 5 minutes, then restart system.

Parts Replacement

Authorized replacement parts and installation procedures.

Note: Use only Fujitsu authorized replacement parts to maintain warranty coverage.

Warranty Information

Fujitsu Airstage warranty terms and service procedures.

Standard Warranty: 5 years on compressor, 1 year on parts and labor from date of installation.

Extended Warranty: Available for registered installations with proper maintenance records.

Warranty Claims: Contact authorized Fujitsu distributor with model number, serial number, and installation date.

Technical Support: Contact Fujitsu technical support at 1-800- Fujitsu or visit www.fujitsugeneral.com

Service Network: Only authorized service providers should perform warranty repairs.

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