Course Description

An HVAC chiller is fundamentally a refrigeration machine. But unlike a window air conditioner that cools air directly, a chiller removes heat from a liquid-almost always water or a water-glycol mixture. That chilled water is then pumped through air handling units or fan coil units to cool building spaces. Chillers fall into two main categories: water-cooled, which reject heat to a cooling tower, and air-cooled, which reject heat directly to ambient air. In commercial buildings, chillers are the most energy-intensive components, often consuming 35 to 50 percent of total HVAC energy. Central chiller plants serve large buildings, hospitals, campuses, and industrial processes. The efficiency of a chiller is measured by how much cooling it delivers per unit of electrical input. Modern chillers increasingly use low-global warming potential refrigerants such as R-1234ze or R-513A. Remember: Proper chiller selection directly impacts first cost, operating cost, and your building’s carbon footprint.

What you'll learn in this course?

• Explain the fundamental refrigeration cycle and how it applies to water-cooled and air-cooled chillers.

• Apply key rules of thumb for chiller sizing, including tons of refrigeration (TR) and kW/ton.

• Identify the ideal approach temperature and condenser water return setpoints for high efficiency.

• Differentiate between constant speed, variable speed, and magnetic bearing centrifugal compressors.

• Calculate part-load performance using NPLV and IPLV metrics to avoid oversizing penalties.

• Troubleshoot low delta-T syndrome and implement corrective piping or control strategies.

• Optimize condenser water reset and chilled water supply reset for real energy savings.

• Select the correct evaporator and condenser types (shell-and-tube, brazed plate, microchannel).

• Interpret chiller performance curves and avoid surge conditions in centrifugal chillers.

• Develop a sequence of operations that prioritizes chiller efficiency across 25% to 100% load.

Prerequisites

• Basic knowledge of HVAC systems and the vapor-compression refrigeration cycle

• Familiarity with chilled-water systems, pumps, controls, and energy calculations is helpful