The average lifespan of a gas furnace is 15 to 25 years. However, lifespan depends on a number of factors, including when the furnace was built, the materials it is made out of and maintenance. More »

The average furnace lasts 15 to 20 years. This life span is typical of a furnace with a stainless or aluminized steel heat exchanger. In contrast, old furnaces with heavy metal heat exchangers last for 30 to 40 years, bu... More »

In the United States, natural gas supplies are expected to last approximately 85 to 92 years, depending on how much natural gas is consumed every year. Around 2,214 trillion cubic feet of natural gas is available for ext... More »

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Lighting a gas furnace involves turning off the pilot valve, lighting the pilot with a long fireplace match, then turning the gas knob to the On position. This process takes less than half an hour. More »

The average furnace lasts 15 to 20 years. This life span is typical of a furnace with a stainless or aluminized steel heat exchanger. In contrast, old furnaces with heavy metal heat exchangers last for 30 to 40 years, bu... More »

Furnaces have an average life expectancy of 16 to 20 years, and EnergyStar.gov recommends replacing furnaces that are more than 15 years old. Other indications for replacement include increased repair frequency, loss of ... More »

The average lifespan of a central air conditioning unit and its components is between 15 and 20 years, but an air conditioner's lifespan can be affected by installation, usage and general maintenance factors, notes SaveE... More »