Document BR6wKLp46KzypLoa7gEZkLn4k

1 i 876: nl1 j; it CHAPTER 44 1949 Guide Owning and^Operating Costs 877 less may be proper, whereas' for larger installations in buildings that are owned outright a period of 10 or 20 years or more may be used. Depreciation due to deterioration and obsolescence must also be con sidered in arriving at the amortization period. Deterioration and mairite-' nance generally go hand in hand. If a long depreciation period is to be Table 5. Approximate Life of Equipment (Including Obsolescence and Deterioration)* 1. Heat Producing Equipment 2. Heat Distributing Equipment (c) Radiation--concealed____________ ____________________________ 3/ Air Handling Equipment fe) Electrical starting equipment______________________ ____ _____ 4. Air Distributing Equipment (b) Outlets, grilles___________________________________________------ Life in Years 15 10 20 TO 12 10 -5 8 10 10 10 10 15 8 10 8 20 20 10 5. Refrigerating Equipment 6. Water Saving Devices (b) Cooling towers^; , . 15 10 20 15 15 10 10 Varies Widely ' * Modern Air Conditioning, Heating and Ventilating, W. H. Carrier, R. . Cherae and W. A. Grant {Pitman Publishing Carp. 1940, p. 66). used, then the item for-maintenance, repair and replacement of wearing parts must be greater than for a short depreciation period. ' Obsolescence depends mainly on time required for the equipment, to become out-moded. Air conditioning, particularly, would probably suffer more from obsolescence in small plants than'in large establishments. In addition the obsolescence of the building or property in which the equip ment is installed may have a similar effect upon the equipment.