A central AC condenser usually lasts 12 to 15 years. In hot climates where it runs most of the year, 10 is more typical; in the north, 20 is possible.
The outdoor unit holds the compressor, which is the heart and the expense. Compressors fail from heat, from running with low refrigerant, and from electrical stress. Capacitors, contactors and fan motors fail more often but cost far less. The indoor evaporator coil can corrode and leak, and on older systems that leak is where the age question usually comes to a head.
Refrigerant matters here more than for any other appliance. Systems built before 2010 mostly use R-22, which is no longer made; a refrigerant leak on an R-22 system is expensive to fix and usually tips the decision to replacement. Systems from 2010 to about 2024 use R-410A, and newer ones use R-454B or R-32. A new outdoor unit generally needs a matching indoor coil.
Makers put the typical life at 12 to 15 years; some say 15 to 20 with good maintenance. ENERGY STAR suggests considering replacement at 10 years because efficiency gains since then are large.
Find the serial number and decode it: Rheem · Ruud · Goodman · Amana (heating and cooling) · Daikin · Carrier · Bryant · Payne · Day & Night · Heil / Tempstar / Comfortmaker / Arcoaire / KeepRite · Lennox · Armstrong Air / AirEase / Concord / Allied · Ducane · Aire-Flo · Trane · American Standard (heating and cooling) · York · Luxaire · Coleman / Evcon · Fraser-Johnston / Champion / Guardian · WeatherKing · Nordyne / Intertherm / Miller / Maytag / Frigidaire / Tappan / Westinghouse / Kelvinator / Gibson / Broan · Comfort-Aire / Heat Controller / Century
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Galvanized, polybutylene, cast iron and the sewer line: what fails, what it costs, what insurance won't cover and how to decide.
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