Chiller O&M Basics

Efficient chiller performance hinges on factors like sizing, location, fluid choice, and maintenance. Neglecting any of these can lead to substantial energy waste and costly repairs. Before, during, and after installation, adhering to basic guidelines can help to prevent issues and optimize your chiller’s capacity and reliability.

Size and Location

Selecting the right chiller size is critical for efficiency. Determine sizing parameters based on thorough calculations of maximum cooling and process load demands. Recognize that cooling loads fluctuate, necessitating a system designed to accommodate changes.

Install the chiller as close to the process as possible to minimize piping, reduce fluid volume, and enhance heat transfer efficiency. Avoid placement near obstructions or heat sources to maintain proper airflow and accessibility for maintenance.

Fluid Selection

Choose fluids carefully, considering type, quality, and treatment. Non-automotive glycols with corrosion inhibitors are suitable for most applications. For subnormal temperatures or high ambient air conditions, use glycol-water mixtures and additives to prevent freezing and maintain water loop cleanliness.


Refer to the manufacturer’s troubleshooting guide for common issues and corrective measures. While only qualified technicians should repair refrigeration circuits, users can perform basic checks to identify problems. Issues like high or low refrigerant pressure shutdowns may indicate water-related issues or improper settings.


Regular maintenance is essential for optimal performance. In air-cooled systems, clean condenser coils to prevent heat insulation and compressor strain. Vacuum or chemically treat condensers, and use filters to prevent clogging.

For water-cooled systems, flush tubes periodically to remove scale buildup and clean strainer screens to maintain flow rates.

Check refrigerant levels for leaks, and inspect electrical connections to ensure safe operation.

Consider using autotuning microprocessor controllers for accurate temperature control, especially when cooling loads vary.

By prioritizing efficiency and reliability through proper sizing, installation, and maintenance, you can minimize energy and labor costs and extend the lifespan of your chiller system.

Mokon has been a leader in the design and manufacture of custom chiller systems for over 65 years. For more information, contact us.