Oil-fired furnaces and boilers are a popular choice in areas of the country with limited access to natural gas, such as the Northeast. Oil-fired furnaces and boilers present an opportunity to use renewable fuels to heat your home. A number of companies are now offering heating oil blended with biodiesel, allowing their customers to reduce their dependence on foreign oil while drawing on a domestic energy source. The biodiesel blends also produce less pollution than pure heating oil.
A number of retrofits are possible for oil-fired furnaces and boilers, but before pursuing any retrofits you should consider the potential added benefits you could receive by simply replacing the furnace. The following retrofits are possible:
Barometric Flue Damper
During your annual service checkup, have your technician perform a draft test. If too much heat is escaping up the chimney, you may need to install a barometric flue damper. The cost is between $100-$300 and could save you about 5% of your fuel cost.
Derating or Replacing Oil Burners
Derating involves installing a lower gallon per hour (GPH) rated nozzle in an oil-fired appliance to reduce fuel use. This process may require reconfiguring the shape and size of the combustion chamber and adjusting the fuel pump pressure or by replacing a conventional oil burner with a flame-retention burner, all of which should be done by a trained professional.
Many gas and oil furnaces in today's homes are oversized, especially if you've upgraded the envelope of your home with new windows and added insulation. A simple way to improve efficiency is by having a qualified technician install an appropriately sized, smaller nozzle. The cost is minimal, and it could cut fuel bills by as much as 10%.
If your burner is old and inefficient (less than 75% Steady State Efficiency (SSE)), you may want to replace it entirely. Upgrading to a modern flame retention burner will increase your burner to 80% SSE or higher. Note that steam boilers should only be derated if the steam system is also modified to remove excess radiators, which can be a complex procedure.
Next Step: Consult with a heating professional to see if derating or replacing your oil burner can help you save on heating costs and improve your system's efficiency.
Modulating Aquastats (For Hot Water Boilers Only)
An aquastat controls the temperature of the hot water in a boiler, typically keeping it around 180°F. However, during the milder spring and fall months, 180°F is often higher than needed and wastes energy. A modulating aquastat, also known as an outdoor reset, senses outdoor temperatures and adjusts the hot water temperature accordingly. These units can save up to 10% on fuel costs and cost several hundred dollars to install.
A more budget-friendly option is to manually adjust the aquastat yourself, lowering it to around 120°F during the milder heating season. Consult your owner's manual or ask a service technician to help you locate and adjust the aquastat.
Next Step: Consider installing a modulating aquastat for automatic energy savings or manually adjust your aquastat during milder months to reduce your fuel costs.
Time-Delay Relay (For Hot Water Boilers Only)
A time-delay relay helps you get the most heat from your system without immediately running the boiler. When the thermostat clicks on, the relay causes the boiler to circulate hot water through the system first, delaying the boiler's ignition. After a set time, the boiler will then fire up. A time-delay relay costs about $100 and can cut your fuel costs by up to 10%.
Next Step: Install a time-delay relay to improve your heating efficiency and start saving on fuel costs.
Take Action
Check out different models of high-efficiency oil-fired boilers and furnaces to find the best fit for your home.
Consult with a professional to evaluate your current system and discuss the best retrofits or replacements for improved efficiency.
Visit our Energy Saver Guide for more tips on how to save energy and reduce your heating costs.
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