ESCO Air Conditioning Practice Exam 2026 – The All-in-One Guide to Exam Success!

The correct choice indicates that scroll compressors operate by utilizing two spiraled elements that compress the refrigerant. Scroll compressors achieve this compression through the interaction of involute spirals, which are specially designed scrolls. When the fixed and moving scrolls engage, the refrigerant is drawn into the spaces between the spirals, and as the scrolls continue to rotate, the volume of these spaces decreases, effectively compressing the refrigerant.

Option A, stating that scroll compressors compress refrigerant with pistons, misrepresents the technology, as scroll compressors do not use pistons for compression. Instead, they rely on the unique design of the spirals to transfer and compress the refrigerant smoothly and efficiently.

Other choices, while they describe various methods of operation found in different types of compressors, do not accurately reflect the functionality of a scroll compressor. For instance, forcing refrigerant through valves is more indicative of typical design in reciprocating or rotary compressors, while rotary blades refer to a different mechanism altogether. Understanding the specific design and operation of scroll compressors helps clarify their efficiency and effectiveness within various HVAC applications.