EXPECTED USEFUL LIFE TABLE Fuel Oil Storage 25 25 Fuel Transfer System 25 25 Heat Exchanger 35 35 Heating Water Circulating Pumps by size by size Line Dryers 15 15 Motorized Valves 12 12 Outdoor Temp Sensor 10 10 Pneu lines & Controls 30 30 Purchased Steam Supply Station 50+ 50+ Solar Hot Water 20 []