Furnace Installation in Boise City, ID
A new furnace here will run from October through May every year. Tell us about the house, and a licensed contractor who covers Ada County will get in touch.
Tell us about the job
It takes about a minute.
Boise winters ask a lot of a new furnace
October through May, this house needs heat. That is 8 months of the year the furnace has to work, with winter nights averaging 25°F. A new furnace here is not a light-duty appliance. It runs most of the year.
Any gas furnace installed today has to reach at least 80 percent AFUE, the federal minimum for non-weatherized models. Power outages happen here too, with 11% of Idaho households going at least a day without power in 2024, and the area has seen 27 winter storms and 41 damaging wind events over the past ten years. Whatever gets installed has to hold up to that.
- 8 months
- October through May, your furnace is on duty
- 25°F
- the average winter night it heats against
- 69%
- of homes here heat with gas, so most furnaces here burn gas
- 80% AFUE
- the federal minimum any new unit must meet
NOAA nClimDiv, 1991–2020 normals
A high-efficiency gas furnace would save about $60 a year to run in Ada County compared with a gas furnace.
Estimates for a typical Ada County home, from EIA household energy data, Idaho fuel prices and NOAA climate normals. Your home will differ.
Idaho requires HVAC contractors to hold a state license.
The state license comes from Idaho's HVAC Board. It belongs to the contractor, not to any single job. It means the person or business doing your install has met the state's requirements and is on record with the board, whatever city or county you're in.
For a furnace install in Ada County, that license is what stands behind the work itself. There is also a local step. Most cities and counties, Ada County included, require a permit before a furnace goes in and an inspection once it's done. In Ada County, 68.9% of homes heat with gas, so a furnace install is common work for both the license and the permit process to cover.
Sources: Idaho Legislature · Idaho Division of Occupational and Professional Licenses
- What size furnace does my house need?
- The right size depends on your square footage, your insulation, your windows, and your home's layout, so there's no single number that fits every house. A contractor sizes a furnace by running a load calculation on your specific home, not by square footage alone. Going too big wastes fuel and wears out the furnace faster from short cycling. Going too small leaves you cold on the coldest nights, and with winter lows here averaging 25°F, that gap shows up fast.
- How do I know it's time to replace my furnace?
- Watch for rising repair calls, uneven heat between rooms, and a furnace that runs longer to keep up. If it's cycling on and off more than it used to, or making noises it didn't make before, those are signs the burner or heat exchanger is struggling. Homes here need heat from October through May, eight months of the year, so a furnace on its way out gets tested a lot before spring gives it a break. If a repair is going to cost close to what a new furnace would, replacing it makes more sense than patching it again.
- Is a high-efficiency furnace worth it?
- It depends on how long you plan to stay in the house and what you're paying for gas now, but the efficiency gain itself is real. Furnaces built since November 2015 have to hit at least 80 percent AFUE, and high-efficiency models go well beyond that, meaning less of the gas you burn goes out the vent unused. With most homes in this area heating with gas and needing that heat for eight months of the year, the difference adds up over a full winter. A contractor can walk you through the specific models and what each one would mean for your house.