What is the maximum allowable temperature differential between makeup air and the conditioned space?

The maximum allowable temperature differential between makeup air and the conditioned space is established to ensure effective integration of makeup air while maintaining comfort and efficiency within the conditioned environment. A differential of 10 degrees is generally recognized as a balance that promotes proper air mixing, reduces drafts, and minimizes the load on heating or cooling systems.

When the temperature differential exceeds this limit, it can lead to discomfort for occupants and increased energy consumption because HVAC systems may have to work harder to adjust to the sudden introduction of significantly warmer or cooler air. Keeping the differential at 10 degrees helps to ensure that the makeup air will adequately match the existing conditions of the space, facilitating a more uniform temperature distribution and improving overall system performance.