Mitsubishi EAHV – Daily Water-Cooled Chiller Maintenance Procedure

Use this checklist to perform daily maintenance of Mitsubishi EAHV water-cooled chillers for consistent performance, energy efficiency, and regulatory compliance.

General System Overview

  • Inspect entire chiller unit and surrounding equipment for visible leaks, wear, corrosion, or physical damage
  • Pay close attention to pipes, insulation, and support structures for integrity
  • Record total operating hours and compressor starts for the day
  • Test all system alarms including high/low pressure, temperature, and low flow
  • Verify alarms are functional and audible at appropriate locations
  • Ensure equipment is operating within expected limits per specifications

Compressor & Refrigerant System

  • Check compressor for smooth operation without unusual vibrations or noises
  • Listen for signs of overheating or mechanical wear
  • Measure refrigerant pressures to ensure within prescribed operating range
  • Check for refrigerant leaks using appropriate leak detection methods
  • Check oil levels in compressor - ensure clean and at correct level
  • Verify oil quality and replace if contaminated or degraded

Heat Exchanger & Cooling Tower

  • Inspect condenser coils for cleanliness and remove debris or dirt buildup
  • Ensure coils are not clogged and clean if needed for efficiency
  • Verify water flow rate through condenser is adequate per specifications
  • Check water temperature entering and exiting condenser meets design specs
  • Inspect cooling tower for debris, scale buildup, or fouling
  • Clean cooling tower basin and verify fan motors functioning properly
  • Ensure cooling tower providing sufficient airflow for heat rejection

Water System & Treatment

  • Verify water circulating properly through system with correct pressure
  • Inspect water pumps for leaks or unusual sounds during operation
  • Check water treatment system for proper chemical dosing
  • Ensure chemicals prevent fouling, scaling, and corrosion in system
  • Test water pH levels for optimal performance
  • Test alkalinity and hardness levels to ensure water quality

Electrical System

  • Inspect all electrical connections for corrosion, wear, or loose terminals
  • Ensure all fuses, circuit breakers, and relays in good condition
  • Inspect motor and fan blades for wear and proper operation
  • Check motor amperage against manufacturer specifications
  • Verify control panel displays correct operational parameters
  • Check for error codes or fault indicators on control panel

Safety & Protection Systems

  • Test all pressure relief valves to ensure working correctly
  • Verify valves are not obstructed or stuck in position
  • Verify emergency shutdown system is operational and responsive
  • Test high and low-pressure cutoffs for correct operation
  • Ensure safety devices operate correctly under fault conditions
  • Verify all emergency stops are clearly labeled and accessible

Performance Monitoring

  • Monitor system performance including cooling output and energy consumption
  • Review temperature and pressure levels against specifications
  • Compare current data with historical data for trends or inefficiencies
  • Review system's energy consumption for the day
  • Check for signs of increased energy usage indicating inefficiency
  • Document any performance anomalies for further investigation

Documentation & Reporting

  • Record all inspections, findings, and corrective actions in maintenance log
  • Include summary of system performance and water treatment conditions
  • Document any issues addressed during the inspection
  • Ensure chiller meets relevant environmental and safety regulations
  • Check compliance with ISO 14001 Environmental Management standards
  • Verify compliance with applicable OSHA safety standards