General HVAC System maintenance checklist

Logging the refrigeration system performance will help identify changes. Obtain the maintenance schedule to ensure the following is being undertaken:


  • Check the temperatures of cold stores.
  • Check evaporator and condenser coils for dirt or debris and clean them if required. Also, check for missing or plugged nozzles.
  • Regularly check the entire piping system, especially joints, seals, valves and glands for leaks.
  • Check the refrigerant sight glass for bubbles. Bubbles in the sight glass often mean a system is leaking. Find the leaks and repair them before the system is recharged with refrigerant. Refrigerant top‑ups should only need to be undertaken annually. Contaminated refrigerant should be purged and automatic purging controls are now readily available.
  • Report and repair any vibrating pipe work, as this is likely to cause a leak over time.
  • Check that compressor oils are at the right level.
  • Check that product is not impeding the air flow of evaporators.
  • Ensure that fans, motors and belts have sufficient air circulation.
  • Check for plugged line filters.
  • Check evaporators are defrosting and pan lines are clearing properly.
  • Report ice on the floor and walls of cold rooms as this indicates that excessive air is entering the room, which becomes a defrosting and safety problem.

Check usage procedures.


  • Check compressor motor temperature and ensure it is operating as recommended by the manufacturer.
  • Check and treat cooling water entering the system. Reduce scale, corrosion and biological growth, as this ensures heat transfer is efficient.
  • Check all oil pump and compressor joints and fittings and all relief valves in the system for leaks.
  • Check all insulation of pipes, valves and cooler or freezer areas for condition and appropriate thickness.


  • Check the compressor motor assembly and oil system to ensure it is operating at maximum efficiency.
  • Clean evaporator and condenser tubes during a shutdown.