Furnace Installation in Rexburg, ID
A new furnace here will run from September through June every year. Tell us about the house, and a licensed contractor who covers Madison County will get in touch.
Tell us about the job
It takes about a minute.
Rexburg asks a furnace to work most of the year
Winter nights here average 14°F, and homes in Madison County need heat from September through June. That is ten months of run time a year, with only a couple months off. A new furnace has to hold up to that kind of use winter after winter.
More than half the homes here heat with gas, and any non-weatherized gas furnace built after November 2015 has to reach at least 80 percent AFUE by federal rule. Power matters too. Idaho saw 11 percent of households lose power for a day or more in 2024, and the region has logged 103 winter storms and 60 damaging wind events over the past ten years. A furnace installed here should be sized and set up with that cold, and those outages, in mind.
- 10 months
- September through June, your furnace is on duty
- 14°F
- the average winter night it heats against
- 54%
- 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 $90 a year to run in Madison County compared with a gas furnace.
Estimates for a typical Madison 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 tested this contractor before handing out that license, and the HVAC Board keeps a record of who holds one. That license belongs to the contractor, not to this one job, so it tells you the person or company has met the state's standard, not that this particular install has been checked.
The check on this specific furnace comes from the local building office. Madison County will need a permit for a furnace installation, and an inspector looks at the work once it's done. That inspection is where a bad gas connection gets caught, which matters here since most homes in Madison County heat with gas.
Sources: Idaho Legislature · Idaho Division of Occupational and Professional Licenses
- What size furnace does my house need?
- The right size comes from a load calculation, not the square footage of your house. A contractor measures your walls, windows, ceiling height and insulation and runs a Manual J calculation to find the number your house actually needs. A furnace that's too big will short cycle and wear out faster. One that's too small will run constantly and still leave you cold on a 14°F night. With heat needed here from September through June, getting this number right matters more than it would somewhere with a short winter.
- How do I know it's time to replace my furnace?
- Watch how often it needs a repair call and how well it heats the house. If you're calling for service more than you used to, or some rooms stay cold while others don't, the furnace is struggling to keep up. A furnace built before November 2015 may also fall short of the 80 percent AFUE minimum required now, which means more of your gas is going up the flue instead of into your house. A contractor can look at its condition and tell you whether a repair still makes sense.
- 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. A high-efficiency furnace burns less fuel to produce the same heat, and with heat needed here from September through June, that difference adds up faster than it would somewhere with a short winter. More than half of homes in Madison County heat with gas, so the fuel savings are real for most of this area. A contractor can walk through what efficiency level makes sense for your house and price the installation.