High-efficiency furnace installation and repair.
Duluth winters do not play. We install and service the gas, propane, and oil furnaces that keep Twin Ports homes safe and comfortable through the deepest cold.
What we cover.
From a new high-efficiency 96% AFUE condensing furnace install to an emergency no-heat repair at 2am in January, we handle the full range of residential furnace work across Duluth, Hermantown, Superior WI, Two Harbors, and Cloquet.
We service every major brand, gas or oil, single-stage or modulating. Our techs carry the parts most no-heat calls actually need, so we fix it on the first visit instead of dragging it into a second appointment.
Signs you need furnace service.
If one of these is happening at your house, do not wait. The longer you run it, the more it costs to fix.
No heat at all
Could be the flame sensor, ignitor, pressure switch, limit, or thermostat. Most no-heat calls fixed first visit.
Furnace short-cycles
Turns on, runs 30 seconds, shuts off, repeats. Usually a dirty flame sensor, a failing limit, or restricted airflow.
Yellow or flickering pilot flame
Sign of incomplete combustion. Possible CO concern. Stop using until we read the flue gases.
Loud bang at ignition
Delayed ignition. Burner manifold needs inspection before it cracks the heat exchanger.
Cold air from the vents
Blower running but burners not firing. Flame sensor or gas valve, usually a quick fix.
Furnace is 15+ years old
Modern 96% AFUE units cut gas use 20 to 30 percent versus an 80% legacy unit. Time for a written comparison.
Four steps from your call to a comfortable home.
Diagnostic visit
$139 trip and full safety check. Combustion analyzer reading, static pressure, flame sensor, ignitor, pressure switches, heat exchanger.
Flat-rate repair or install quote
Real price in writing. No hourly meter, no upsells, no surprise add-ons at checkout.
Same-day or scheduled work
Most no-heat calls fixed same visit. New installs typically completed in one day with full venting and permits.
Commissioning and follow-up
Final combustion tune, gas pressure check, blower amperage, then we walk you through the new system.
Real numbers, before you call.
We are not afraid to publish prices. Final quotes are flat-rate, written, and itemized after we see your system.
Diagnostic visit
- Combustion analyzer, static pressure, every safety circuit
- Heat exchanger inspection included
- Flat-rate repair quote before any wrenches turn
Common furnace repair
- Flame sensor, ignitor, pressure switch (parts on truck)
- Inducer motor or capacitor replacement
- Gas valve or limit switch swap
New high-efficiency furnace
- Sized to the actual heat loss, not the old unit's nameplate
- PVC or stainless vent run, condensate neutralizer
- Permit, commissioning, 1-year labor warranty
Includes oil and propane furnaces. Sidewall venting may add $200 to $600 depending on routing. 24/7 emergency rate is the same flat-rate as scheduled work.
Why homeowners pick Northland Air for furnace.
Combustion analyzer on every visit
We do not just relight the pilot. We measure CO, O2, and stack temp so your furnace runs safe and efficient, not just running.
Heat exchanger inspection included
Cracked heat exchangers leak carbon monoxide. Our standard tune-up includes a full inspection, not a sales pitch.
We carry the parts
Most no-heat calls in winter are flame sensors, ignitors, pressure switches, capacitors. We stock them on the truck so we fix it today.
What homeowners say about our furnace work.
Furnace died at 6am on a Tuesday in February. Called Northland Air at 6:15. Tech was at my door at 8am with the part already on the truck. Heat back on by 8:45. Best service experience I have ever had with a trade.

Brands we service and install: Trane · Carrier · Lennox · Goodman · Bryant · Rheem · American Standard
Why every visit gets a combustion analyzer reading.
A combustion analyzer measures the actual flue-gas mix on your furnace: carbon monoxide (CO), oxygen (O2), stack temperature, and combustion efficiency. It is the only way to know whether the unit is burning safely and at full efficiency.
We have walked into homes where the previous tech "fixed" a furnace that was producing 400 ppm of CO into the living space. That is dangerous and it is invisible without an analyzer. Every Northland Air visit gets a reading at startup and at shutdown. If the numbers are wrong, you find out before we leave.
Standard on every tune-up, every diagnostic, every install commissioning. No upsell.
Furnace questions, answered.
Most high-efficiency residential gas furnace installs land between $4,200 and $8,800 in the Twin Ports, depending on size, AFUE rating, and venting requirements. Itemized written quote every time.
Quality residential furnaces last 18-25 years when they are properly sized, maintained annually, and have a clean filter. We see plenty of well-maintained Lennox and Carrier units cross 22 years in service.
Once per year, every fall, before the first cold snap. A real tune-up is a 60-90 minute job that catches problems before they catch you at midnight in January.
Yes, we service oil furnaces and oil-fired boilers across the Twin Ports and North Shore.
$139 covers a complete safety and operational check. Combustion analyzer reading, static pressure, every safety circuit, flame sensor, ignitor, pressure switches, blower wheel inspection. Waived when you approve repair same visit.
Not necessarily. If your AC is recent and operating well, we can usually re-use the existing line set and outdoor unit. We confirm at the quote.
Available across the Twin Ports.
Same-day furnace service in your neighborhood.