CSLB Class B General Contractor's License Practice Exam

A standard air conditioning unit moves how many cubic feet of air per minute per ton?

1. 400

2. 600

3. 300

4. 500

The correct answer is: 600

In the context of air conditioning, the performance of a standard air conditioning unit is often measured in terms of its capacity to move air. One ton of air conditioning capacity typically moves about 400 to 600 cubic feet of air per minute (CFM). The most commonly accepted standard in the industry for calculating airflow per ton of cooling is 400 CFM. However, a more typical operational figure, especially in commercial settings, is often approximated at 600 CFM. Therefore, selecting 600 CFM per ton of cooling is justified as it aligns with the industry practice of ensuring adequate airflow for proper system performance and comfort. This flow rate helps to maintain the efficiency of the cooling process, ensuring that the system is cooling effectively while also supporting humidity control. It’s important for contractors to be familiar with these standards to make informed decisions about system design and to ensure comfort in the spaces they are cooling.