Furnace System GuideConverting from oil heat to a natural gas furnace is a common upgrade in areas with a gas main at the street. The choice turns on fuel availability, efficiency, and installed cost. The efficiency and usage facts below come from dated ENERGY STAR and EIA sources. Any tax incentive is caveated because those rules change, and unverifiable local details are left to a contractor.
Natural Gas Is the Dominant Home Heating Fuel
Access to natural gas is the first question in any conversion. If a gas main runs to the property, connecting a new gas furnace is usually straightforward; if not, the cost of extending service can change the whole calculation.
Natural gas already heats a large share of American homes. The U.S. Energy Information Administration reports that about 60 percent of U.S. homes use natural gas for space and water heating, cooking, and clothes drying, which is why the fuel is widely available in developed areas.
Efficiency of the New Gas Furnace
A conversion is a chance to install a high-efficiency unit, since the old oil furnace is being removed anyway. The efficiency rating you choose sets the long-run fuel savings.
ENERGY STAR sets its gas furnace bar at 97 percent AFUE or greater for the U.S. North and 95 percent AFUE or greater for the U.S. South. For comparison, its oil furnace requirement is 87 percent AFUE or greater, so a certified gas furnace generally converts a higher share of fuel into heat than a comparable oil unit.
Savings and Payback
The savings from a conversion come from both a more efficient furnace and, in many areas, a lower fuel price per unit of heat. A high-efficiency unit narrows the amount of energy wasted up the flue.
ENERGY STAR estimates certified gas furnaces are up to 18 percent more energy efficient than baseline models in the northern United States, with about $160 a year in energy savings, and up to 16 percent more efficient in the south. Local fuel prices, install cost, and the price of extending gas service determine the real payback period, which a contractor should model for your address.
Safety and Venting After the Switch
A conversion changes the combustion and venting on the appliance, so proper installation and inspection are not optional. Any fuel-burning furnace produces exhaust that must be vented correctly to keep carbon monoxide out of the living space.
The EPA recommends keeping gas appliances properly adjusted and having a trained professional inspect, clean, and tune up the central heating system annually. It also notes the CPSC recommends every home have carbon monoxide alarms on each level outside each sleeping area, which is essential once a gas furnace is in service.
Check Incentives Before You Commit
A high-efficiency gas furnace may qualify for a federal tax credit that offsets part of the conversion cost. These programs change, so confirm the current rule before you rely on it.
ENERGY STAR lists furnaces among improvements eligible for 30 percent up to $1,200 in energy efficiency credits and states homeowners may claim the maximum annual credit every year that eligible improvements are made through 2025. Verify present eligibility and amounts with ENERGY STAR and the IRS, and ask your utility about any local conversion rebate.
Frequently asked questions
Is converting from oil to gas worth it?
It turns on fuel availability, efficiency, and installed cost. If a gas main runs to the property the connection is usually straightforward; if not, extending service can change the whole calculation, so have a contractor model the payback for your address.
Is a gas furnace more efficient than oil?
Generally yes at the certified level. ENERGY STAR sets its gas furnace bar at 97 percent AFUE or greater in the North and 95 percent in the South, versus 87 percent or greater for oil furnaces.
What safety steps come with the switch?
The EPA recommends keeping gas appliances properly adjusted and having a trained professional inspect and tune up the heating system annually, and notes the CPSC recommends carbon monoxide alarms on each level outside each sleeping area.
Are there incentives for the conversion?
Possibly, but confirm before you commit. ENERGY STAR listed furnaces among improvements eligible for 30 percent up to $1,200 in credits through 2025; verify current eligibility with ENERGY STAR and the IRS, and ask your utility about local rebates.