Gas furnaces can be powered by natural gas (from a utility company) or propane (LP). Capacity is measured in British thermal units (one BTU is the amount of energy needed to raise the temperature of a pound of water by one degree Fahrenheit). A furnace rated 50,000 BTU consumes 50,000 BTUs an hour.
Typical costs:
Furnaces that are the heart of a gas central heating system are typically sold by an HVAC (heating, ventilation and air conditioning) contractor, with installation included, and the AFUE rating is a major factor in the price. Replacing an aging gas furnace with a standard-efficiency model (80% AFUE, which means that 80% of its fuel is converted to heat) starts at about $1,700-$4,000, including installation, but depending on complexity and location it can cost $5,000-$8,000 or more.
Installing a new high-efficiency (90%-97% AFUE) gas furnace starts at about $2,500-$6,000 but depending on complexity and location it can cost $7,000-$12,000 or more. CostHelper readers report paying $2,695-$5,000 for basic installation of a 95%-96% gas furnace, at an average cost of $3,465.
Replacing an oil furnace with a gas-fired model can cost thousands of dollars more than replacing one gas furnace with another, because of the cost to remove the old oil tank ($500-$3,000 or more) and to install new gas lines, fittings, valves and other parts of the system to work with the new gas furnace. A CostHelper reader reports paying $6,500 to replace an oil furnace with a gas unit.
A wall-mounted gas furnace that provides hot air directly to the surrounding space can cost $400-$2,500 for just the unit, depending on size, BTUs, AFUE rating, air outlet location (top outlets are typically slightly cheaper than bottom outlet models) and the controls (a wall-mount or cabinet-mount thermostat or a remote control). Installation can bring total costs to $1,400-$5,000 or more. For example, the low-profile (25.25" high, 22.25" wide, 9.5" deep) HouseWarmer HWDV181BDV 18,000 BTU Wall Furnace[1] vents directly on an outside wall, has a built-in blower and thermostat, is rated to heat up to 525 square feet and costs about $500-$830 (without installation) in propane or natural gas.
Replacing a gas floor furnace (the heat rises from a grill flush with the floor) typically costs about $900-$2,500 for just the unit, depending on size, BTUs and features like the type of thermostat; installation brings the total cost to $2,000-$4,500 or more. At 14" wide the Cozy Challenger 90N30 Narrow 30,000 BTU Natural Gas Floor Furnace[2] fits between standard 16" floor joist spacing and costs about $900-$1,000 without installation.
A furnace in a central heating system typically has a burner, where the fuel is delivered and consumed; a heat exchanger (or exchangers) to transfer heat from the burner to the air; and blowers/fans to distribute the heated air into the ductwork. Mr. Fix-It has a detailed overview[3] that includes basic terms and standard system set-ups.
Additional costs:
A building/mechanical permit is usually required to replace a furnace. Fees are typically about $50-$300 or more. Many contractors include getting the proper permits and inspections as part of the installation process.
Replacing aging, leaking or inadequate ductwork typically costs about $35 -$55 a linear foot for labor and materials, or $1,000-$5,000 or more for a single-family home, depending on the length and type of ducts.
Replacing a low- or mid-efficiency furnace with a high-efficiency model may require installing a chimney liner for about $300-$700.
Discounts:
The database of State Incentives for Renewables & Energy Efficiency[4] tracks energy-efficiency incentives offered by utilities and by state, federal and local government agencies. For example, utility companies in Wisconsin[5] pay a $125 "reward" for furnaces with a 90% AFUE rating and $275 for 95% models.
Shopping for a gas furnace:
The Environmental Protection Agency lists tips for hiring a heating and cooling contractor[6] .
Referrals are available from the North American Technician Excellence certification program[7] and the Air Conditioning Contractors of America[8] .
Request and check references; ask about length and type of experience; and be sure they are properly bonded, insured and licensed[9] . Check for complaints with the Better Business Bureau[10] .
10 Quick and Inexpensive Home Makeover Projects To Do While At Home You may not be able to host the large family gathering for the holidays, but there are still many ways to pick up items curbside to spruce up your indoor space for your everyday enjoyment and to bring a more festive spirit. || Posted December 30 2020
10 Key Ways to Prepare for Extreme Snow Forecasters are predicting a true nor'easter will hit the eastern and central states with rain, thunderstorms, ice, snow and high winds over the Thanksgiving weekend. It's crucial to plan ahead, before bad weather hits. || Posted November 26 2013
Very good service. Job done in 3 hours.
10 years Warrantee on parts, 1 year on labor.
American Standard, 120,000 BTU for 2300 SQ house.
Quite, safe and warm now.
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