What are the AMBIENT and GROUND zones?
AMBIENT and GROUND are SUNREL keywords that can be input for backside of Walls. AMBIENT tells SUNREL to model the exterior conditions of the wall using only the outdoor air temperature from the weather file (i.e. no solar or wind effects are modeled). This option is useful when modeling surfaces that do not see the sun such as an elevated floor. The GROUND keyword tells SUNREL to model the exterior conditions of this wall using the Ground Temperature specified in the RUNS input section. Q: I am having a hard time understanding exactly how to use the leakage fraction % in the “wall” section… what is it, and what kind of number can you assign there? The same goes for the leakage fraction in the “exterior surfaces” section. A: There are two methods of modeling infiltration: (1) with a fixed air change per hour, which can be scheduled; or (2) with an effective leakage area (ELA), which calculates the infiltration every time step. If you input an ELA, the leakage area can be divided among
