ITEM                   EQUIPMENT LIFE         YEARS
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Air Conditioners       Residential             15
                       Through-the-wall        15
                       Water Cooled            15
                       Computer Room           15
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Heat Pumps             Air to Air              12
                       Water to Air            19
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Commercial Package     Single Zone             15
                       Multi Zone              15
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Boilers                Steel Water-tube        24
                       Cast Iron               30
                       Electric                15
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Furnaces                                       18
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Unit Heaters                                   18
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