Furnace Installation in Mankato, MN
A new furnace here will run from October through May every year. Tell us about the house, and a licensed contractor who covers Blue Earth County will get in touch.
Tell us about the job
It takes about a minute.
Mankato winters ask a lot of a furnace
Your furnace here runs eight months a year, October through May, on nights that average 10°F. That is most of the calendar spent working, not a few cold snaps. A new furnace going into that kind of run time needs to be sized and installed right from the start, because it will not get an easy season to break itself in.
Most furnaces manufactured today have to reach at least 80 percent AFUE, and that is the floor, not a selling point. Blue Earth County has also seen its share of winter storms and wind events over the past ten years, and power loss during one of those is what leaves a gas furnace unable to start even though the gas is on. Worth asking your contractor how the model they install handles that.
- 8 months
- October through May, your furnace is on duty
- 10°F
- the average winter night it heats against
- 65%
- 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 $110 a year to run in Blue Earth County compared with a gas furnace.
Estimates for a typical Blue Earth County home, from EIA household energy data, Minnesota fuel prices and NOAA climate normals. Your home will differ.
Minnesota has no state license for HVAC contractors.
Minnesota does not put HVAC contractors through any state test or file them anywhere, so there is no license number to check and no state record of who did this kind of work before. That is true whether the job is a furnace, a water heater, or anything in between. The protection here does not come from the state at all.
For a furnace install, that protection comes from the local building office instead. In most cities and counties, replacing a furnace needs a permit and an inspection once the work is finished, and that inspection is what catches a bad gas connection or a venting mistake before it becomes dangerous. With 64.7% of homes in Blue Earth County heating with gas, that inspection is doing real work here, not just paperwork.
Source: Minnesota Office of the Revisor of Statutes
- What size furnace does my house need?
- It depends on your square footage, how well the house is insulated, your ceiling height, and how many windows you have. A furnace that is too big will short cycle, turning on and off before it heats the house evenly. One that is too small will run constantly and still not keep up on the coldest nights here. A contractor sizes it with a load calculation that looks at your actual house, not just a rule of thumb based on square footage.
- How do I know it's time to replace my furnace?
- Watch for repairs that keep coming back, a furnace that struggles to keep the house warm, and a blower or heat exchanger that is starting to fail. An older furnace nearing the end of its life will show these signs early in the heating season, not just on the coldest nights. Since homes here need heat from October through May, that is a long stretch to be running on a furnace you cannot count on. If you are calling for repairs more than once a season, it is worth having a contractor look at the whole unit, not just the part that broke.
- Is a high-efficiency furnace worth it?
- It depends on how much you heat and how long you plan to stay in the house. With heat needed here eight months a year and winter nights averaging 10°F, a furnace runs a lot more than it would somewhere milder, so the efficiency difference adds up over a season. Every non-weatherized gas furnace made since November 2015 has to reach at least 80 percent AFUE, and high-efficiency models go well above that, meaning less gas burned for the same heat. A contractor can walk you through the options for your house and let you weigh the difference yourself.