Energy-Efficient Gas Hot Water Boilers
The vast majority of homes with central heating systems use either a forced air furnace or hot water boiler to generate heat that is then distributed throughout the home. As energy costs continue to rise, homeowners are understandably concerned about the energy efficiency of these devices, particularly during the winter when energy costs spike. By making a few simple calculations, you can easily determine ways to maximize the energy efficiency of your gas-fired hot water boiler. Does this Spark an idea?
-
Hot Water Boilers
-
Boiler systems use a gas burner to heat water and distribute either steam or hot water to each room in order to heat the room. Boilers that use steam as a heat source are generally less efficient than those that use water, since the water has to be heated to a higher temperature to be converted into steam. It is important to understand that within each type of boiler, there are many makes and models that all vary according to their energy efficiency.
AFUE
-
The energy efficiency of furnaces and boilers is measured using a metric known as AFUE, or annual fuel utilization efficiency. AFUE measures the percentage of energy that a boiler or furnace uses in one year and determines the percentage of the energy that is converted to thermal energy. In other words, a boiler with an 80 percent AFUE rating will convert 80 percent of the fuel used in a year into thermal energy, with the other 20 percent being lost to inefficiency of one kind or another. The higher the AFUE rating, the more energy efficient the boiler, so always shop around for a furnace with a high AFUE rating when you replace your boiler.
-
Retrofits
-
Several parts of a gas-fired boiler can be replaced with more energy-efficient counterparts to improve the energy efficiency of the boiler without the substantial costs involved in replacing the entire boiler. These retrofit components include vent dampers, intermittent ignition devices (to replace less efficient continuous pilot lights), derating gas burners, modulating aquastats and time-delay relays. These devices should be installed by a professional to ensure that the devices will deliver energy cost savings for your boiler.
Other Factors Affecting Efficiency
-
There are many other factors that determine the energy efficiency of a gas-fired hot water boiler, including the size of the entire unit, the age and mechanical condition, temperature at which you operate the furnace, the price of gas in your individual area and many others. In general, the best ways to improve the efficiency of your gas-fired boiler is to replace any boiler that is more than 15 years old with one that has a high AFUE rating, to keep the boiler in good mechanical condition and to retrofit the boiler with more energy efficient parts.
-
