Mitsubishi EAHV-P – Weekly Chiller Maintenance Procedure

Weekly maintenance checklist for Mitsubishi EAHV-P screw vapor chillers to ensure continuous performance, system reliability, and operational compliance.

General System Overview

  • Thorough visual inspection for wear, corrosion, or physical damage
  • Record and analyze weekly operating hours and compressor starts
  • Review alarm history for recurring issues or patterns
  • Check equipment room conditions and ventilation adequacy
  • Verify all gauges and indicators are functioning properly

Compressor & Refrigerant System

  • Inspect compressor for smooth operation, vibrations, and unusual noises
  • Measure and record refrigerant pressures at various load conditions
  • Check oil level and quality for contamination or discoloration
  • Verify oil heater operation to prevent refrigerant migration
  • Check vapor injection system pressures and temperatures
  • Monitor slide valve operation through capacity range

Electrical Components

  • Inspect all electrical connections for tightness and corrosion
  • Check motor amperage against specifications at current load
  • Verify control panel displays accurate readings and status
  • Test all switches and buttons for proper operation
  • Check VSD cooling fans and filters if equipped

Water Systems

  • Verify chilled water flow and pressure within optimal range
  • Check condenser water flow for sufficient circulation
  • Inspect and clean water strainers as needed
  • Check pump operation and inspect for leaks or unusual noise
  • Verify water treatment chemical levels and adjust as needed
  • Monitor approach temperatures for heat exchanger efficiency

Heat Exchangers

  • Inspect condenser and evaporator for dirt, scale, or debris buildup
  • Check approach temperatures and compare to baseline values
  • Clean coils as necessary to maintain heat transfer efficiency
  • Verify proper water distribution across heat exchanger surfaces
  • Check for signs of tube fouling or biological growth

Safety & Protection Systems

  • Test pressure sensors and verify proper operation
  • Test temperature sensors and high/low alarms
  • Verify emergency shutdown system functionality
  • Check flow switches for proper operation and cleanliness
  • Test oil pressure safety controls and alarms

Performance Monitoring

  • Calculate weekly average system efficiency (kW/ton)
  • Compare performance parameters with expected values
  • Review energy consumption patterns and identify anomalies
  • Analyze capacity utilization and load profiles
  • Document vapor injection system efficiency performance
  • Identify optimization opportunities for next week

Documentation & Reporting

  • Complete weekly inspection log with all findings
  • Update maintenance records and equipment history
  • Document any corrective actions taken
  • Note items requiring follow-up or monthly service
  • Update preventive maintenance schedule as needed