OPERATIONS & MAINTENANCE MANUAL - McCormick PCS Info

MAINTENANCE MANAGEMENTOPERATIONS & MAINTENANCE MANUALC • 2/Page 4 of 8No. C • 2Overtime HVACCalculation ExampleStep One -- Electrical CostsA. Water Chilling Unit(1) Condition #1 -- Minimum Load (4 AHUs):Design KW per Ton x minimum load = Total Ch.71 x 30% of 300 Tons = Total Chiller KW at condition #1.71 x 90 = 63.90 KW(2) Condition #2 -- Other Load (5 AHUs):Design KW per Ton x load = Total Chiller KW at condition #2.71 x (min. load in tons : number of AHUs run at min. load)x 5 = Total Chiller KW at condition #2.71 x (90 : 4) x 5 = 79.9 KW at condition #2(3) Condition #3 -- Other Load (6 AHUs):Design KW per Ton x load = Total Chiller KW at condition #3.71 x (min. load in tons: number of AHUs run at min. load)x 6 = Total Chiller KW at condition #3.71 x (90 : 4) x 6 = 95.85% KW at condition #3NOTE: Carry out the calculation to the extent necessary.© 1992 - 1997, Michael Robert McCormickAll Rights Reserved