How Long Will a Hot Water Baseboard Furnace Last?

Boiler vs. Furnance

• A boiler uses oil, gas or electricity to generate hot water, which is piped to baseboard radiation systems. A furnace, on the other hand, burns oil or gas to heat air that is forced by a fan through a large, ducted system and blown through registers throughout the house.

Life Span

• The average life span of a boiler depends on the type. For example, electric boilers average 13 years and gas boilers last about 21 years, according to the September 2005 issue of "Appliance Magazine," cited in a 2007 study by the National Association of Home Builders and Bank of America. Life span is just one issue when considering boilers, the Houseinspect website notes. A cast iron boiler has the same parts and way of working as a steel boiler. The cast iron boiler costs more but has a longer life span: 30 years or more. Steel boilers last about 20 years but heat more quickly than cast iron and lose less heat, helping to save fuel.

Maintenance

• Maintaining boilers well helps them reach their expected life span. ConsumerReports.org recommends checking the system annually -- by turning it on and seeing how it heats -- and dusting baseboard radiators before cooler weather starts. The rest should be left to a professional, who should check the pressure-relief valve and high-limit control. Excessive pressure damages boilers, shortening their life span. The professional should also clean the system, look for water pump leaks, and inspect the cold and hot system pressure, the fill valve, the automatic air vents and the expansion tank.

Replacing a Boiler

• Besides when it is old and worn out -- that is, when the boiler needs frequent repairs or when replacement parts are hard to come by -- the U.S. Department of Energy's Energy Star website recommends replacing a boiler if it is more than 15 years old, has older features and is oversized. The efficiencies of older boilers are in the 56 to 70 percent range, but modern systems have efficiencies as high as 97 percent, which means almost all of the purchased fuel heats the home. According to the Department of Energy, efficiency upgrades often cut fuel bills and the furnace's pollution output by 50 percent. Before buying a new boiler, make your home more energy-efficient by sealing air leaks, for example, then have a heating professional size the furnace. Purchase a boiler with an Energy Star label for a 5 percent higher efficiency than other new models.