Residential HVAC Installation Practice Exam

What happens to the cfm calculation if the volume of the house is increased?

1. Cfm decreases

2. Cfm increases

3. No change in cfm

4. Cannot calculate without additional information

The correct answer is: Cfm increases

When the volume of a house is increased, the cubic feet per minute (cfm) calculation for HVAC systems needs to increase as well to effectively heat or cool the larger space. This is because more air volume needs to be circulated to maintain the desired temperature throughout the expanded area. Therefore, the correct answer is B: Cfm increases. Option A is incorrect because as the volume of the house increases, the airflow requirements also increase to adequately heat or cool the larger space. Option C is incorrect because there is a direct relationship between the volume of the house and the cfm calculation for HVAC systems. As the volume increases, the cfm must also increase to maintain comfort levels. Option D is incorrect because, with the knowledge that the volume of the house has increased, it is possible to determine that the cfm calculation needs to be adjusted accordingly to suit the new dimensions of the space.