Actual furnace and boiler efficiency is a function of three factors: 1) the type and age of the system 2) ability of the system to distribute heat 3) the occupant's control of the system A heating technician can determine the combustion efficiency of your furnace or boiler by utilizing a combustion analyzer. Combustion efficiency is the amount of heat in a fuel source that is converted to heat for a home. If a furnace has a heating efficiency of 60%, that means that 40% of your heat bill is wasted to the outside. The combustion analyzer is able to calculate how much energy is going out the chimney. The manufacturer may also have an efficiency rating on the nameplate of the furnace. The manufacturer's rating is based on proper installation and does not necessarily guarantee the equipment is running at the stated efficiency. The actual efficiency can only be determined with a combustion analyzer.  If your furnace is operating below the stated efficiency a tune-up will be required in order to increase the performance of the furnace. Some older furnaces may only be able to reach efficiency levels of 70-75%, so it may be beneficial to install a new furnace with efficiency levels in the 90-95% range. If the duct work of the furnace is leaky, it is not going to deliver the optimum heated air to the intended space. If the duct work runs through a cold crawlspace or attic, the heat in the duct work will cool down rapidly before reaching the intended space. To remedy these problems, duct work should be sealed with specialized mastics or tape and then insulated. Lastly, to improve the energy efficiency of your heating system it is critical that the heating supply and return registers remain clean and unobstructed. Keep toys, furniture, and other household furnishings clear of the heating system air flow.

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