NATE Air Conditioning and Heat Pumps Practice Exam

A cooling load calculation estimates the sensible heat gain of a structure. The maximum sensible capacity of a cooling-only system should be within ____% of this calculated value.

1. ±10%

2. +10%

3. +15%

4. +30%

The correct answer is: +15%

The correct answer focuses on the allowable maximum sensible capacity of a cooling-only system in relation to the calculated sensible heat gain of a structure. A system should be able to handle fluctuations in cooling load effectively, ensuring optimal performance and efficiency. The guideline suggests that the maximum capacity of the cooling system should be within 15% above the calculated sensible heat gain. This range allows for variations caused by unexpected factors such as increased occupancy, additional heat sources, or changes in environmental conditions that may increase the actual load beyond initial calculations. By maintaining a capacity within this limit, the system can maintain comfort levels without facing issues like short-cycling, which can lead to inefficiencies and increased wear on the equipment. This percentage is a common industry standard that balances performance, cost-effectiveness, and system longevity.