HVAC repair & installation in Duluth, MN
Twin Ports HVAC takes calls for HVAC repair and installation in Duluth, MN and across the bridge in Superior: furnaces, boilers, ductless heat pumps and central air.
Mon–Sat, 9am–6pm · Duluth, MN & Superior, WI
68°
HEAT · SET
−20°
90°
Duluth's year, by the thermostat
Nine months a year, the average high never reaches 68°.
Each bar is a month's average low to average high at the Duluth airport. Everything under the dashed line is work for the furnace or the boiler. Only June, July and August poke above it, and only in the afternoon.
68° inside
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
3.8°
Average January low. The furnace runs almost without a break on those nights.
79°
Average July high, the warmest month. Air conditioning here is about a few humid weeks, not a season.
Nov
Average high 38°. The month a furnace that limped through spring stops limping.
Source: NOAA monthly climate normals, 2006–2020, Duluth International Airport (station USW00014913).
What we work on
Two settings on every thermostat. Both covered.
Most calls in the Twin Ports are about heat: a furnace that quit, a boiler that won't keep up, a system that's done. The rest are the summer kind. Pick what yours is doing.
HEAT
Furnaces and boilers
Gas furnaces, hot-water and steam boilers, and the yearly check before the first cold snap.
Furnace repair
No heat, short-cycling, ignition and flame-sensor faults
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Furnace replacement
High-efficiency furnaces sized for a Northland winter
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Boiler installation & repair
For Duluth's older homes with radiators and hydronic heat
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Furnace inspections & tune-ups
Burners, flame sensor, heat exchanger, venting and CO
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COOL
Air conditioning and heat pumps
For the few weeks a year a Duluth bedroom won't cool off, and for heat pumps that work both ways.
Before you call
What your furnace is telling you, and what to try first.
The same kind of chart that's taped inside a furnace door, in plain words. If the first thing to try doesn't fix it, call: the cause is usually a part, not a setting.
Troubleshooting · gas furnace
Keep the door panel on while it runs
No heat, and the thermostat is calling for it
Starts, runs a few minutes, shuts off
Blowing cold air from the vents
Water on the floor by the furnace
Banging, squealing or rattling
You smell gas, or the CO alarm is sounding
General guidance for common gas furnaces. Your furnace's own manual comes first.
Ductless mini-splits
Heat and air for the rooms the ducts never reached.
A cold-climate mini-split is a heat pump with one or more indoor heads and no ductwork. In Twin Ports homes they go into additions, finished attics, sunrooms, garages and houses heated by a boiler, usually alongside the heat that's already there.
Heats
Well below zero (cold-climate models)
Cools
Room by room in summer
Ductwork
None: a small line set through the wall
Best with
A furnace or boiler as backup
Questions people ask us
What happens after you reach out
Three steps from "it's cold in here" to a quote.
1
Tell us what it's doing
Call, or send the form with what you're seeing: the sound, the smell, the error light, how old the system is if you know.
2
We call you back
We ask the questions that narrow it down and set a time to look at it, at your house in Duluth, Superior or nearby.
3
You get the quote before the work
Repair or replace, you see the price first and decide. A system near the end of its life gets both options side by side.
Service area
Both sides of the bridge, and up and down the shore.
Duluth and Superior first, then the towns a short drive out: Hermantown, Proctor, Rice Lake, Esko, Cloquet and Two Harbors. If you're not sure you're close enough, call and ask.
Oliver, WI
Scanlon
Carlton
Poplar, WI
Lake Nebagamon, WI
Moose Lake
Twin Ports HVAC
Service area
Miles from downtown Duluth, as the crow flies
Questions
Asked before most furnace calls.
Should I repair my furnace or replace it?
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Age and the size of the repair decide it. A gas furnace often lasts 15 to 20 years. A repair on a furnace under about 10 years old is usually worth it; past 15, with a big repair like a heat exchanger or an inducer motor, replacing it is often the better money. You get both prices to compare.
How often should a furnace be inspected?
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Once a year, before the heating season. In Duluth that means September or October, before the first week of nights below freezing, when everyone calls at once.
Can a mini-split heat a house in a Duluth winter?
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A cold-climate model can keep heating well below zero, and many homes use one as the main heat for part of the house. Most keep a furnace or boiler as backup for the coldest nights. Sizing and where the heads go matter more than the brand.
Boiler or furnace: what's the difference?
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A furnace heats air and blows it through ducts. A boiler heats water and sends it to radiators, baseboard or in-floor tubing. Many older Duluth and Superior homes were built for boilers; switching one to the other is a bigger job than replacing like for like.
Do you work in Superior, Wisconsin?
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Yes. Superior is five minutes across the bridge, and the towns south of it on the Wisconsin side too. Rebates differ by state: Focus on Energy in Wisconsin, your utility in Minnesota.
Free quote
Tell us what your furnace is doing.
A few lines are enough to start. We call back to ask the rest, and you get a price before any work.
Furnaces, boilers, air conditioning and mini-splits
Duluth, Superior and the towns around the harbor
The price first, then your decision