Mitsubishi EACV – Monthly Chiller Maintenance Procedure

Use this checklist for monthly maintenance of Mitsubishi EACV centrifugal chillers to ensure safety, energy efficiency, and reliable operation.

General System Overview

  • Perform thorough inspection of entire chiller system for leaks, corrosion, cracks, or physical damage
  • Inspect piping, insulation, and support structures for integrity
  • Check operating hours and verify equipment is within monthly service intervals
  • Review complete alarm history for recurring issues or patterns
  • Verify all monitoring systems are functioning correctly
  • Document equipment condition with photographs where applicable

Compressor & Refrigerant System

  • Inspect compressor for wear and tear, listen for abnormal sounds (grinding, rattling)
  • Check refrigerant pressure levels against manufacturer specifications
  • Perform comprehensive leak detection using electronic leak detector
  • Take oil sample for laboratory analysis
  • Inspect and replace compressor oil if contaminated or degraded
  • Test oil heater functionality and temperature regulation
  • Verify proper operation of oil pump and oil pressure
  • Check compressor vibration levels and compare to baseline

Electrical System

  • Confirm correct voltage, amperage, and frequency per specifications
  • Inspect all electrical connections, tighten as necessary
  • Check control panels, circuit breakers, and safety switches for damage or wear
  • Test motor insulation resistance
  • Verify proper motor lubrication and bearing condition
  • Check fan operation and ensure unobstructed air circulation
  • Perform thermographic scan of electrical components
  • Test ground fault protection systems

Water & Cooling System

  • Check chilled water flow rate, pressure, and temperature differential
  • Verify pumps and valves are functioning optimally
  • Inspect condenser water flow rate and temperature parameters
  • Test water treatment system and chemical levels
  • Clean water strainers and filters
  • Check for scaling, fouling, or biological growth
  • Verify proper operation of water flow switches
  • Test and calibrate water temperature sensors

Heat Exchangers

  • Perform visual inspection for fouling or scaling on condenser and evaporator
  • Clean coils thoroughly as required
  • Inspect airflow through heat exchangers
  • Clean fans and remove debris blocking airflow
  • Check tube bundle condition for corrosion or damage
  • Verify heat transfer efficiency through approach temperature analysis
  • Inspect and clean refrigerant distribution system

Safety & Protection Systems

  • Test all high/low pressure safety switches
  • Verify temperature sensors and limit switches
  • Perform full emergency shutdown system test
  • Test refrigerant leak detection systems
  • Verify proper operation of all relief valves
  • Check and update safety signage and labels
  • Review and update emergency procedures documentation

Performance Monitoring

  • Assess system efficiency by comparing operational parameters with historical data
  • Review monthly energy consumption trends
  • Calculate current kW/ton efficiency
  • Identify optimization opportunities
  • Verify capacity control system operation
  • Review and adjust operating setpoints as needed
  • Generate monthly performance report

Control System & Calibration

  • Back up all control system parameters and settings
  • Calibrate temperature sensors and transducers
  • Calibrate pressure sensors and switches
  • Test and verify control sequence operations
  • Update control software if newer versions available
  • Clean control panel and check display functionality

Documentation & Reporting

  • Record all inspection findings and maintenance actions in detail
  • Update equipment maintenance log with current data
  • Document any issues addressed and parts replaced
  • Verify compliance with environmental and safety regulations
  • Generate monthly maintenance report for management
  • Schedule follow-up maintenance as required