Generally 6″ (150mm) height concrete pad or steel stand. This is the peak load seen by the cooling coil in the Air Handling Unit for the HVAC system. Air handling units, which usually have the acronym of A.H.U are found in suppose i have USGPM and KW. PrecisionCoils Selection. Engineering Book Store The heat load estimate is based on your climate region, total square footage, number of rooms or zones you want, ceiling height, insulation type, number of windows and doors. The thermal load is estimated in units of BTUs. The design is accomplished through discretizing the cooling co il into N segments according to the number of the coil rows. else