ESP=ΔPStraight Duct+ΔPFittings+ΔPAccessoriescap E cap S cap P equals cap delta cap P sub Straight Duct end-sub plus cap delta cap P sub Fittings end-sub plus cap delta cap P sub Accessories end-sub
ESP represents the total workload the blower faces outside the main equipment cabinet. It is the sum of pressure drops across external components like: esp calculation hvac excel sheet