Air Conditioning: Save Energy and Money with Preventive Maintenance

Key Points

Preventive maintenance can improve cooling system performance and minimize costly breakdowns.
Inspect all components for leaks, dirt and other signs of wear, and clean and repair as needed.
Energy-saving measures, such as installing ceiling fans, can further reduce cooling costs.

While air conditioning systems are critical to occupant comfort and worker productivity, repairing or replacing them can be expensive. Preventive maintenance on major system components reduces the risk of costly breakdowns and helps to ensure that the system is operating efficiently — saving energy and money.

Refrigerant circuit and controls

Inspect the moisture liquid indicator (sight glass) to ensure that no moisture is in the system.
Check for and repair refrigerant and oil leaks around equipment seals, pipe joints, valves and other instrumentation.
Make sure refrigerant levels are properly balanced.Inspect the tension and alignment of all belts and adjust as needed.
Lubricate motor bearings and all moving parts.

Compressor

Inspect the compressor and check amp draw.
Check all compressor joints for leaks.
Look for unusual compressor operation, including continuous running or frequent stopping and starting.
Visually observe compressor oil color and level.

Air-cooled condenser

Check the fan drive and motor to make sure they are aligned and lubricated properly.
Ensure that refrigerant piping connections to the condenser coil are tight.
Clean condenser coils, fins and tubes.
Make sure the temperature difference between the outside air and the condenser fan discharge air is appropriate.

Evaporative condenser

Inspect piping joints and check for leaks.
Check for dirt on the coil surface.
Inspect the air inlet screen, spray nozzles, water distribution hoses and the pump screen.
Follow the manufacturer's guidelines regarding fan and pump maintenance.

Cooling towers

Conduct a chemical analysis to determine if solid concentrations are maintained at acceptable levels.
Inspect the V-belt and the alignment of the fan and motor.
Ensure that the tower and the intake strainer are clean.
Inspect spray-filled and gravity distributed towers to ensure the nozzles are clean.
Monitor the effectiveness of any water-treatment programs.

Air-handling units

Verify that economizers are enabled and working properly.
Cycle dampers open and closed periodically.
Adjust damper actuators to achieve full damper closure.
Lubricate serviceable (not sealed) blower shaft bearings.

Saving energy

The following measures can help you get the most out of your cooling system and keep your building comfortable all summer long.

Set the building temperature at 78°F during business hours and program thermostats to save energy by adjusting temperatures according to occupancy.
Install ceiling fans wherever possible; they make occupants feel cooler, reducing the need for air conditioning.
Check for and seal air leaks in windows and doors, as well as exterior plumbing and wiring access points.
Install window film, solar screens or awnings on south-facing windows to reduce solar heat gain.