Daikin WLPB – Monthly Chiller Maintenance Procedure

Use this checklist for monthly maintenance of Daikin WLPB vapor absorption chillers to ensure efficient, safe, and sustainable operation.

Comprehensive System Inspection

  • Thorough visual inspection of entire chiller system including insulation integrity
  • Check all flanges, valves, and connections for leaks using soap solution
  • Inspect structural supports and vibration isolators for deterioration
  • Verify operating hours log and compare with maintenance schedule
  • Test all local and remote alarm systems for proper function
  • Review and update equipment documentation and drawings

Solution Analysis & Management

  • Perform complete lithium bromide solution analysis with laboratory equipment
  • Measure and record specific gravity at multiple temperature points
  • Check solution pH and adjust if outside 9.
  • Verify corrosion inhibitor levels and add as necessary
  • Calculate crystallization margin at current operating conditions
  • Clean solution pump strainers and check for debris

Heat Exchanger Performance

  • Calculate and trend approach temperatures for all heat exchangers
  • Inspect tube sheets for signs of erosion or corrosion
  • Check absorber and condenser spray nozzles for proper pattern
  • Verify evaporator refrigerant level and distribution
  • Clean accessible heat transfer surfaces if fouling detected
  • Document heat transfer efficiency for trending analysis

Electrical System Verification

  • Inspect and tighten all electrical connections with torque wrench
  • Check motor amperage draw and compare to nameplate ratings
  • Verify proper operation of variable frequency drives if equipped
  • Test insulation resistance on motors with megohmmeter
  • Inspect control panel for signs of overheating or component wear
  • Verify proper grounding of all electrical components

Vacuum System Analysis

  • Perform detailed vacuum leak test using helium leak detector
  • Change vacuum pump oil and inspect for contamination
  • Test purge unit efficiency and adjust operating parameters
  • Inspect all gaskets and O-rings for deterioration
  • Verify rupture disk integrity with pressure test
  • Document vacuum trends and purge frequency for analysis

Water System Maintenance

  • Perform complete water analysis for pH, hardness, and dissolved solids
  • Clean water strainers and inspect for debris accumulation
  • Verify water treatment chemical feed rates and adjust as needed
  • Check flow rates and pressure drops across all water circuits
  • Inspect cooling tower fill and drift eliminators if applicable
  • Document water usage and blowdown rates for efficiency tracking

Control System Calibration

  • Calibrate all temperature sensors using certified thermometer
  • Verify pressure transducer accuracy with test gauge
  • Test and adjust control valve actuators for proper stroke
  • Update control system software and firmware if available
  • Verify setpoints and control logic for optimal efficiency
  • Document all calibration results for compliance records

Safety Systems Testing

  • Test crystallization protection system with simulated conditions
  • Verify emergency dilution cycle completes within time limits
  • Test all safety interlocks and document response times
  • Inspect and test pressure relief devices for proper operation
  • Verify emergency shutdown procedures with operators
  • Update safety documentation and emergency contact information

Performance Analysis

  • Calculate monthly average COP and compare to baseline
  • Analyze heat source consumption trends and costs
  • Review capacity utilization and load profile data
  • Compare actual performance to manufacturer specifications
  • Identify efficiency improvement opportunities
  • Generate monthly performance report for management review