Safety Running a Furnace on a Generator During an Outage A gas furnace can run on a generator, and in a climate where a long outage in January is a genuine hazard it is a reasonable thing to plan for. The furnace itself… October 6, 2026 · 8 min read

Propane Propane Regulators, Snow and Deep Cold A propane furnace that ran perfectly in November and locks out on the coldest night of January has usually not broken. It has been starved. Everything between the… October 5, 2026 · 8 min read

Propane Fuel Oil Heat: Annual Care and When to Convert Fuel oil still heats a lot of houses across this service area, particularly older ones outside the gas mains, and it remains a perfectly workable way to heat a… October 4, 2026 · 8 min read

Water Heaters Do Heat Pump Water Heaters Work in Cold Basements? Heat pump water heaters have gone from unusual to common in the Twin Ports, and they are one of the few pieces of equipment where the answer genuinely depends on… October 3, 2026 · 8 min read

Water Heaters Why Does My Water Heater Pilot Keep Going Out? A gas water heater pilot going out once in a long while can be a fluke. A pilot that goes out every few days is a fault, and it is usually one of four, each of… October 2, 2026 · 8 min read

Water Heaters Anode Rods and Flushing: Make a Water Heater Last A tank water heater is a steel vessel with a thin glass lining, and it lasts as long as that steel stays protected. Two things protect it: a sacrificial anode rod… October 1, 2026 · 8 min read

Boilers Outdoor Reset: The Boiler Control That Pays Off Most boilers in this region were installed to do one thing: heat water to a fixed setpoint, all winter, whether it is a damp October afternoon or a −17°F January… September 30, 2026 · 8 min read

Boilers Combi Boilers in a Cold Climate: Pros and Cons A combi boiler is an appealing idea in an old northern house: one wall-hung box replaces the boiler, the water heater and often a chimney connection, and it gives… September 29, 2026 · 8 min read

Radiant Adding Radiant Floor Heat to a Basement A basement in the Twin Ports is the coldest surface in the house, sitting on ground that stays cold all year. That is exactly why a warm floor is so noticeable down… September 28, 2026 · 8 min read

Garage & Shop How to Heat a Garage in Minnesota: Real Options A heated garage in this climate is the difference between a space you use nine months a year and one you use twelve. The catch is that a detached garage is close to… September 27, 2026 · 8 min read

Ductwork Ice Dams and Your Heating System: The Connection Ice dams form when snow on the upper part of a roof melts, the water runs down to the cold overhang, and it refreezes there into a ridge that backs the next… September 26, 2026 · 8 min read

Indoor Air Why Are My Windows Sweating or Icing Up in Winter? Condensation on the inside of a window is the indoor air telling you its dew point is higher than the glass temperature. Warm air holds water vapor; cold surfaces… September 25, 2026 · 7 min read

Indoor Air Bypass, Fan-Powered or Steam: Which Humidifier Type? Heating air does not remove water from it, but it does drive relative humidity through the floor, and a Twin Ports winter is long enough that most houses spend… September 24, 2026 · 8 min read

Ductwork Why Is the Upstairs Colder in Winter? It is the most common comfort complaint we hear in the Twin Ports between November and March: the main floor is fine, sometimes too warm, and the bedrooms upstairs… September 23, 2026 · 8 min read

Commercial How to Improve Ventilation in an Office or Shop The complaint usually arrives by mid-afternoon: the office feels stuffy, the air seems stale, people are drowsy or say they get headaches that ease once they step… September 22, 2026 · 7 min read

Air Conditioning Can You Add Central Air to an Old House With Radiators? Many older Duluth hillside houses were built around hot-water or steam radiators and have never had a single duct. Adding cooling to one of them is entirely… September 22, 2026 · 7 min read

Commercial Does Your Commercial Kitchen Need a Hood? Almost every restaurant, café, commissary and church kitchen reaches the hood question at some point: when a new fryer arrives, when a lease is on the table, or… September 22, 2026 · 6 min read

Commercial Unit Heaters for Shops and Warehouses: Types and Sizing If you own a shop, a warehouse, a machine shed or a big detached garage, the heater hanging from the rafters is almost certainly a unit heater. It is the workhorse… September 22, 2026 · 7 min read

Radiant Is Radiant Floor Heating Worth It in a Cold Climate? Radiant floor heating is one of the most comfortable ways to heat a house in a climate like ours, and it is also one of the easiest to overspend on. Whether it is… September 22, 2026 · 8 min read

Commercial What Drives the Cost of a Commercial HVAC Replacement? Owners who see their first commercial HVAC replacement quote are often surprised by how far it is from the price of the unit itself. The gap is not padding. It is… September 22, 2026 · 7 min read

Commercial Landlord or Tenant: Who Pays for HVAC in a Commercial Lease? When a rooftop unit fails in January, the first question in a leased building is often not how to fix it but who pays. This article explains the arrangements… September 22, 2026 · 7 min read

Commercial Commercial vs Residential HVAC: What Actually Differs Small business owners often ask whether they need a commercial HVAC company or whether the contractor who services their house will do. The answer depends on what… September 22, 2026 · 7 min read

Commercial What a Building Automation System Actually Does Owners and managers of small and mid-size commercial buildings often inherit a building automation system without ever being told what it does. There is a computer… September 22, 2026 · 6 min read

Commercial How Long Does a Commercial Boiler Last? Owners of apartment buildings, schools, churches and older commercial buildings ask how long a boiler lasts because they need to put a line in a capital plan. The… September 22, 2026 · 7 min read

Commercial What a Make-Up Air Unit Does, and When You Need One Restaurant owners usually meet the phrase "make-up air" in one of two ways: a contractor mentions it while quoting a new hood, or the kitchen gets so cold and… September 22, 2026 · 7 min read

Commercial Why Is My Walk-In Cooler Freezing Up? A walk-in cooler that is freezing up usually shows it in one of two ways: a white block of frost building on the evaporator coil near the ceiling, or product at the… September 22, 2026 · 7 min read

Commercial How Long Does a Rooftop Unit Last in the Twin Ports? Building owners ask how long a rooftop unit lasts because they are trying to put a line in a capital budget. The honest answer is that the number of years matters… September 22, 2026 · 8 min read

Air Conditioning What Size Air Conditioner Do I Need? Most people asking this question are hoping for a chart: this many square feet, this size unit. Those charts exist, and in this part of the country they point a lot… September 22, 2026 · 7 min read

Air Conditioning Why Is My AC Leaking Water Inside the House? Water on the basement floor in July usually traces back to the air conditioner, even though the part making the water sits indoors. The evaporator coil that cools… September 22, 2026 · 7 min read

Air Conditioning Why Is My Air Conditioner Freezing Up? Ice on an air conditioner looks like a system working too hard, which is why people are surprised to learn the opposite is true. You might find frost on the larger… September 22, 2026 · 8 min read

Thermostats Where Should a Thermostat Be Located? A thermostat does not know how warm your house is. It knows how warm the air is at one spot on one wall, and it runs the furnace, boiler or heat pump until that… September 22, 2026 · 7 min read

Thermostats What Thermostat Messages Mean: Wait, Recovery, Aux Thermostat messages are short on purpose, and that makes them easy to misread. Most of the words that show up on a modern display, such as WAIT, RECOVERY, AUX and… September 22, 2026 · 8 min read

Heat Pumps Is a Mini-Split Worth It in a Duluth House? Whether a mini-split beats central air comes down to one question in this region: does the house already have ductwork worth using? Many Duluth houses were built… September 22, 2026 · 7 min read

Heat Pumps Why Is My Mini-Split Leaking Water Inside? A mini-split head drips water into the room when the condensate it produces in cooling mode is not getting out through its drain. Every indoor head has a cold coil… September 22, 2026 · 8 min read

Water Heaters Water Heater Not Making Hot Water? Gas vs Electric The first question is whether your water heater burns gas or runs on electricity, because the two fail in completely different ways. A gas heater has a burner under… September 22, 2026 · 7 min read

Water Heaters Why Is My Water Heater Leaking? Top vs Bottom A puddle under a water heater has only a handful of possible sources, and the location of the water sorts them almost completely. Water coming from the top of the… September 22, 2026 · 8 min read

Boilers How Often Should a Boiler Be Serviced? The short answer is once a year. A boiler runs for most of the year in a climate where the heating season commonly stretches from late September into May, and it is… September 22, 2026 · 7 min read

Boilers Why Does My Boiler Keep Shutting Off? A boiler that keeps shutting off is doing one of two very different things, and sorting out which one is the first step in any boiler repair visit. Short cycling is… September 22, 2026 · 8 min read

Boilers Why Is My Boiler Leaking Water? Start With Where The quickest way to answer why a boiler is leaking is to find exactly where the water is coming from before you wipe it up. A hot-water boiler has only a handful of… September 22, 2026 · 7 min read

Heat Pumps Can a Heat Pump Use Your Existing Ductwork? If your house already has forced-air heat, a ducted heat pump can almost always connect to the ductwork you have. The outdoor unit sits on a pad or bracket, the… September 22, 2026 · 7 min read

Heat Pumps Why Does My Heat Pump Blow Cool Air in Winter? Cool air from the registers is the most common complaint in the first winter after a cold-climate heat pump installation, and most of the time nothing is wrong… September 22, 2026 · 7 min read

Heat Pumps What Emergency Heat Means on a Heat Pump Thermostat Every ducted heat pump thermostat in the Twin Ports has two backup-heat labels on it, and most owners find out what they mean the first time one lights up on a… September 22, 2026 · 7 min read

Ductwork Is Air Duct Cleaning Worth It in an Older Duluth House? People ask us about duct cleaning more than almost anything else, usually because the house is dusty, a room never warms up, or the air feels stale by February. So… September 22, 2026 · 7 min read

Maintenance Why Is My Furnace Filter Black, Greasy or Damp? Every furnace filter gets dirty, and most of what collects on one is skin flakes, fabric fibers, pet dander and mineral dust. That kind of loading is grey, fuzzy… September 22, 2026 · 8 min read

Furnaces Furnace Keeps Tripping the Breaker or Blowing a Fuse A circuit breaker is a deliberately weak link. When it opens, it has decided that the current flowing through the furnace circuit is higher than the wire behind it… September 22, 2026 · 8 min read

Furnaces Why Is There Water Around My Furnace? Water on the floor under a furnace is alarming in a way a strange noise is not, because water and a gas appliance feel like they should never share a room. The… September 22, 2026 · 8 min read

Indoor Air Furnace Fan On or Auto: Which Should You Use? Nearly every thermostat in the Twin Ports has a fan switch with two positions, ON and AUTO, and almost nobody is told what they do. AUTO ties the blower to the… September 22, 2026 · 8 min read

Thermostats Thermostat Screen Blank? Check These Before You Call A dark thermostat is not usually a dead thermostat. It is a thermostat with no power reaching it, and the supply comes from one of two places: batteries inside the… September 22, 2026 · 8 min read

Furnaces Furnace Noises and What Each One Means Furnaces make noise, and the useful skill is knowing which noises are the equipment working and which are the equipment telling you something. The sound itself… September 21, 2026 · 8 min read

Furnaces Burning Smell When the Furnace Starts: Normal or Not? Almost every furnace in Duluth and Superior smells slightly of hot dust the first time it runs in the fall, and almost none of them have anything wrong with them… September 20, 2026 · 7 min read

Thermostats The Best Thermostat Settings for a Minnesota Winter There is no single right number on a thermostat, but there is a right method, and it depends more on what kind of heating system you have than on what the… September 19, 2026 · 8 min read

Commercial A Fall Rooftop Unit Checklist for Twin Ports A packaged rooftop unit spends the Twin Ports summer doing one job and the winter doing a completely different one, using a section of itself that has been sitting… September 18, 2026 · 8 min read

Indoor Air HRV or ERV: Which Ventilator for a Cold Climate? Build or air-seal a house tightly enough and it stops ventilating itself, which is the point — but the stale air, cooking moisture, shower moisture and everything… September 18, 2026 · 8 min read

Propane What Happens If a Propane Furnace Runs Out of Fuel? When a propane tank runs dry the furnace stops, but the more important consequence is what happens to the system. Pressure in the lines falls to nothing, the safety… September 18, 2026 · 8 min read

Water Heaters Do Tankless Water Heaters Work in a Cold Climate? Tankless water heaters are a genuinely good fit for some Twin Ports households and a poor fit for others, and which one you are depends almost entirely on… September 18, 2026 · 7 min read

Furnaces Why Does My Furnace Condensate Line Freeze? There is a specific no-heat call that arrives in the coldest week of every winter and nowhere else in the year: a high-efficiency furnace that has been running all… September 18, 2026 · 8 min read

Furnaces 80% vs 96% Furnace: Which Makes Sense Up North? Every furnace quote in Duluth and Superior eventually comes down to this choice, and it is not really a choice between two numbers. An 80% and a 96% furnace are… September 18, 2026 · 8 min read

Furnaces What Size Furnace Does a Northern MN House Need? Sizing is the decision that determines whether you like a new furnace for the next twenty years, and it gets made in about four minutes on most quotes. Matching the… September 18, 2026 · 8 min read

Heat Pumps How Many Mini-Split Heads Does a House Need? Most Twin Ports houses need two to four mini-split heads, not one for every room. A head serves a zone — a volume of air that mixes freely and wants the same… September 18, 2026 · 8 min read

Heat Pumps What Temperature Should Dual-Fuel Switch to Gas? A dual-fuel system is a heat pump and a gas or propane furnace sharing one duct system and one thermostat, with a control deciding which one heats the house at any… September 18, 2026 · 7 min read

Heat Pumps Is Steam Coming Off My Heat Pump in Winter Normal? Twice on a cold afternoon, a heat pump will stop blowing warm air, go quiet outside, make a sound like a large sigh, and then start steaming as if something is… September 18, 2026 · 8 min read

Boilers Why Do My Radiators Bang, Hiss and Gurgle? The Twin Ports has a housing stock built for coal and converted twice since, and a large share of the hillside in Duluth and the older neighborhoods in Superior… September 18, 2026 · 8 min read

Boilers Boiler Pressure Too High or Too Low? Read the Gauge The pressure gauge on a hot water boiler is the cheapest diagnostic tool in the house, and almost nobody looks at it until water is on the floor. It tells you… September 18, 2026 · 8 min read

Boilers How to Bleed a Radiator (and When Not To) A radiator that is hot along the bottom and cold across the top has air trapped in it, and bleeding that air out through the valve at the top corner is a genuine… September 18, 2026 · 8 min read

Safety Carbon Monoxide Alarms and Your Heating System Carbon monoxide is colorless, odorless and produced by every fuel-burning appliance in the house when combustion goes wrong. You cannot smell it, and the symptoms… September 18, 2026 · 7 min read

Furnaces Snow or Ice Blocking Your Furnace Vent: What to Do Go outside, find the two PVC pipes coming out of the wall near the furnace, and clear snow away from both openings with your hands or a broom. Most furnaces restart… September 18, 2026 · 7 min read

Furnaces Ignitor or Flame Sensor: Which One Failed? Two of the most common no-heat calls in the Twin Ports produce completely different sounds at the furnace, and once you know what to listen for you can tell a… September 18, 2026 · 8 min read

Furnaces Why Is My Furnace Blowing Cold Air? 7 Causes Cold air out of the registers means the blower and the burners have come apart from each other. Either the blower is running on its own, or the burner fired and a… September 18, 2026 · 8 min read

Maintenance How Often to Change a Furnace Filter in Winter Change a 1-inch disposable filter about once a month through the heating season, and change a 4–5-inch media filter roughly once a season. Those are starting… September 18, 2026 · 8 min read

Furnaces When Should You Turn On Your Furnace in Duluth? The right week to start your furnace in the Twin Ports is the one where nothing is riding on it. Late September, a mild afternoon, windows closed, nobody in a… September 18, 2026 · 7 min read

Maintenance What a Fall Furnace Tune-Up Should Actually Include A furnace in this climate runs far more hours than the same furnace in a mild one, because Duluth and Superior sit in a roughly 9,000–10,000 heating-degree-day… September 18, 2026 · 8 min read

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