I have 2 - 20 ton units, 1 - 10 ton unit, 1 - 7.5 ton unit, and 1 - 5 ton unit of air conditioning load. Can somebody give some direction on how to calculate AC load for service sizing when there is this many different size units. Are there some demand factors that can be used? If I add all MCA's together that would be a 125% calculation on every unit and would not be correct? The service will by 120/208 3 phase.