Preventive maintenance for chillers involves cleaning, monitoring temperature and pressure, and general system testing. Depending on the maintenance tasks, technicians must perform them anywhere from daily, weekly, monthly, or annually.
What is a Chiller?
A chiller is a machine that removes heat from a liquid via a vapor-compression or absorption refrigeration cycle. This liquid can then be circulated through a heat exchanger to cool air or equipment as required.
What are the common preventive maintenance schedules of a Chiller?
Depending on the chiller types you are considering, the key schedules may vary slightly. For example, the points on a water-cooled chiller maintenance schedule won’t necessarily apply to air-cooled chillers.
Few tips for maintaining your industrial chillers are below
Maintain your daily logs
Keep the Chiller Tubing Clean
Monitor for refrigerant leaks
Reduce the temperature of Condensor Water
Inspect the condenser water loops
Monitor the glycol concentration
Maintain an Optimal Chilled Water Flow Rate
Keeping air and moisture out of your chiller system
Examine the Compressor Oil
Inspect Motors and Starting Mechanism
Install Variable Speed Drives
What are the main components of the Chiller?
Compressor: Provides the energy system.
Condenser: Rejects heat gained by the gas using ambient air or cooling tower water to condense the gas back to a liquid for use again by the evaporator. The condenser is a heat exchanger, which dissipates the heat absorbed in the evaporator.
System Expansion: The liquid refrigerant enters the expansion device which reduces pressure. By reducing its pressure abruptly decreases its temperature.
Evaporator: Cools the water, water/glycol, or air by transferring the heat to the refrigerant which is turned into a gas. Compressor – takes this gas and increases its pressure so that ambient air or water can remove the heat. The coolant at low temperature and pressure through the evaporator, which like the condenser is a heat exchanger and absorbs heat.
Holding Tank: holds the circulating coolant, usually water (can be water/glycol), tank is sized large enough to prevent turbulent flow in the tank causing pump cavitation.
Pump: Circulates coolant from the holding tank to the evaporator and from the evaporator to the machine or process being cooled and back to the tank.
Control Panel: Houses temperature controller, compressor contactor, pump starter, 3-phase fuses, control transformer, safety controls, run and fail lights.