An unfinished basement containing a gas furnace with ductwork in the foreground and miscellaneous stored items along the far concrete wall.

Furnace vs Boiler in Madison County, Illinois

When a furnace makes sense

If your house already has ductwork, a furnace is the straightforward choice. Most homes in this region are set up this way, and the same ducts that heat your home through those 25°F nights can carry central air in summer. You are not paying to open up walls or run new lines, just to heat through what is already there.

When a boiler makes sense

If your home heats through radiators or in-floor pipes rather than ductwork, a boiler is the machine built for that system. It runs about 5% cheaper than a furnace here, and with 7 months of heating season that difference shows up on the bill every winter. It will not move air for central cooling, so it suits a house where that was never part of the plan.

When a furnace makes sense

If your house already has ductwork, a furnace is the straightforward choice. Most homes in this region are set up this way, and the same ducts that heat your home through those 25°F nights can carry central air in summer. You are not paying to open up walls or run new lines, just to heat through what is already there.

When a boiler makes sense

If your home heats through radiators or in-floor pipes rather than ductwork, a boiler is the machine built for that system. It runs about 5% cheaper than a furnace here, and with 7 months of heating season that difference shows up on the bill every winter. It will not move air for central cooling, so it suits a house where that was never part of the plan.

A gray forced-air furnace with sheet-metal ductwork stands in an unfinished basement with exposed wooden joists, concrete walls, and a hanging incandescent bulb.

Furnace

Runs on
Natural gas
What it does
Heats only
Tax credit
No federal tax credit since the end of 2025

Sources: U.S. Department of Energy · Internal Revenue Code

A gray boiler with copper pipes and a pressure gauge stands in an unfinished basement with wooden stairs and concrete floors.

Boiler

Runs on
Natural gas
What it does
Heats only
Tax credit
No federal tax credit since the end of 2025

Sources: U.S. Department of Energy · Internal Revenue Code

Furnace wins in Madison County.

In the Great Lakes states, 78.8% of homes heat with a furnace, so most already have the ductwork it needs.

About 5% lessto heat with a boiler than with a furnace, at Illinois prices
25°Faverage winter low
61%of homes here heat with gas

If your home already has radiators or in-floor pipes instead of ductwork, a boiler is still the better choice.

Find a contractor
Compared onFurnaceBoiler
Cost to run hereCosts more to runAbout 5% less to run
What it doesHeats onlyHeats only
Homes in the Great Lakes states that heat with one78.8%7.7%
Handles a 25°F nightYesYes

Sources: U.S. Energy Information Administration, U.S. Department of Energy, NOAA

When a furnace makes sense

If your house already has ductwork, a furnace is the straightforward choice. Most homes in this region are set up this way, and the same ducts that heat your home through those 25°F nights can carry central air in summer. You are not paying to open up walls or run new lines, just to heat through what is already there.

When a boiler makes sense

If your home heats through radiators or in-floor pipes rather than ductwork, a boiler is the machine built for that system. It runs about 5% cheaper than a furnace here, and with 7 months of heating season that difference shows up on the bill every winter. It will not move air for central cooling, so it suits a house where that was never part of the plan.

A Madison County contractor will price both against your own house, your ductwork and your panel.

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