Even when a chiller is inspected and maintained regularly, problems such as those listed above can occur over time.

Even when your chiller is inspected and maintained regularly, its performance can degrade or deteriorate over time. Pumps can fail, process lines can clog, refrigerant can leak, and any number of problems associated with component aging or changing environmental conditions can occur (table 1).

Following are some initial steps to take to help isolate the problem:
  • Make sure that the chiller is running. A blown circuit breaker or fuse, loose wiring, or simply a power switch that’s been put in the “off” position might be preventing the chiller from running.
  • Determine whether the chiller is cooling. Check the temperature of the coolant at the chiller’s outlet to the process. If it isn’t at or near the setpoint temperature, the evaporator might be iced up or the heat transfer properties of the coolant fluid might be deteriorating.
  • Confirm that the pump is running. A closed or partially closed valve, failed pump, inadequate coolant volume or process line restriction might be preventing the adequate flow of liquid through the process coolant loop.
  • Check the process and environmental conditions. The load on the chiller might be too great due to changes in the process or the ambient temperature. Other conditions that can affect the chiller’s heat removal capabilities include a change in the location of the chiller (near other heat-generating equipment or farther from the process equipment); loose, damaged, or missing insulation on the piping between the chiller and the process; or fluctuations in line voltage.