Here's a helpful list of the average life expectancies of some common home appliances, components, equipment and systems. The list is a range and could vary based on other factors such as quality, proper application, amounts of usage, etc. Cast Iron Boilers--30 to 60 years Steel Boilers--20 to 50 years Heat Pump Compressors--10 to 15 years A/C Electric Compressors--12 to 20 years A/C Coils--25 to 30 years A/C Fans--25 to 40 years Gas Water Heater--10 to 15 years Electric Water Heater--10 to 15 years Fiberglass Roof Coverings (reinforced asphalt shingles)--18 to 25 years Asphalt Roof Coverings--20 to 24 years Slate Roof Coverings--35 to 200 years depending on hardness and quarry taken from Metal Roof Coverings--50 to 90 years Aluminum Gutters and Downspouts--18 to 25 years Aluminum Siding--20 to 30 years Vinyl Siding--25 to 35 years Wood Windows--35 to 100 years Aluminum Windows--10 to 25 years Vinyl Windows--20 to 40 years Refrigerators--15 to 20 years Dishwashers--13 to 18 years G...