Carrier Furnace Error Codes: What the Blinking Light Means
Carrier furnace error codes from the maker's own troubleshooting guides: how to count the flashes safely, what each code means, and when to call a tech.
Read the guideHeating Guides
Furnaces, boilers and everything that keeps a Minnesota house warm from October to April.
A Minnesota furnace runs from October into May, and most of the calls we take in January come down to a handful of parts: the igniter, the flame sensor, the pressure switch, the inducer motor, a clogged filter or a frozen vent pipe. These guides walk through what each symptom usually means, what you can safely check yourself, and when to shut the system off and call.
They also cover the bigger decisions: when a furnace is worth repairing, what a replacement costs, how 80% and 96–98% AFUE furnaces differ, and whether a boiler or radiant floor makes sense in an older house. For hands-on help, see furnace repair or furnace replacement.
Goodman Furnace Error Codes and Blinking Lights
Goodman and Amana furnace error codes from Goodman's own service manuals: how to read the display safely, what E0, E1, E2 and others mean, and when to call.
Read the guideHow Old Is My Furnace or AC? Find the Date on the Data Plate
Find your furnace or AC's age on the data plate, then the install sticker or permit record. Serial decoder charts disagree by brand. Call 612-429-3465.
Read the guideLennox Furnace Error Codes: Blinking Lights and Alerts
Lennox furnaces report faults through DS1 and DS2 blinking lights and S30 or iComfort alerts. Learn what they mean and which checks are safe before you call.
Read the guideRheem and Ruud Furnace Error Codes: What They Mean
Rheem and Ruud furnace error codes from Rheem's own 801T manual: what 11, 22, 33, 55 and 57 mean, how to read the display, and when to call a technician.
Read the guideTrane and American Standard Furnace Error Codes
Trane and American Standard furnaces share one control board and flash chart in the maker's guide. See each code, how to read it safely, and when to call.
Read the guideYork Furnace Error Codes: What the Flashes Mean
York furnace error codes from the TM9E installation manual: what 1 to 11 red and 4 amber flashes mean, how to read the LED safely, and when to call.
Read the guideWhat Should I Set My Thermostat to in a Minnesota Winter?
68–70°F while home and awake, lower at night, never below 55°F when away. What setbacks save in Minnesota, how heat pumps differ, and how to keep windows dry.
Read the guideWhat Does the Blinking Light on My Furnace Mean?
A blinking furnace light is a control board fault code. How to read it safely, what common codes mean, and when to call 612-429-3465 instead of resetting.
Read the guideHow Long Does a Furnace Replacement Take?
Most furnace replacements take one day; venting, a chimney liner, gas line or duct work can add a second. Ours run $4,500–$9,500 installed. Call 612-429-3465.
Read the guideOrphaned Water Heater: Why a New Furnace Needs a Liner
An orphaned water heater is left alone in a chimney sized for two appliances after a 90%+ furnace goes in. Why it drafts poorly, the CO risk and the fixes.
Read the guideWhy Is My Thermostat Screen Blank?
A blank thermostat screen usually means lost power: dead batteries, a breaker that is off, a blown board fuse or a condensate float. What to check first.
Read the guideWhat Is a Manual J Load Calculation?
A Manual J load calculation works out how much heating and cooling your house needs: the inputs, why copying the old nameplate oversizes, and what to ask.
Read the guideWhat Size Furnace Do I Need for a Minnesota House?
Furnace size comes from a Manual J heat loss at a -15°F design day, not square feet. Input vs output BTU, AFUE, why old furnaces run big and what to ask for.
Read the guideWhat a Boiler Expansion Tank Does and Signs It's Failing
A boiler expansion tank absorbs water that swells as it heats. How it works, what the pressure gauge tells you, and why a dripping relief valve is the clue.
Read the guideIs a Communicating HVAC System Worth It in Minnesota?
A communicating HVAC system links thermostat, furnace and outdoor unit by data. The features it adds, the lock-in, and when it pays off in Minnesota homes.
Read the guideWhat Is a Furnace Inducer Motor? Signs It's Failing
The inducer motor is the small fan that starts first and pushes exhaust out the vent. Noises and codes of a failing one, repair vs replace, and cost.
Read the guideFurnace Pressure Switch: What It Does and Why It Trips
A furnace pressure switch proves the inducer is venting exhaust before the gas can open. Why it trips in a Minnesota winter, what you can check, and the cost.
Read the guideWhat Does It Mean When a Furnace Is Red-Tagged?
A red tag means a technician or the gas utility found your furnace unsafe and shut it off. Common reasons, what not to do, and how to get a second opinion.
Read the guideWhat Is Static Pressure in HVAC, and Why Does It Matter?
Static pressure is the resistance your blower pushes against in the ducts and filter. Why it matters for a new furnace or AC, the symptoms and the fixes.
Read the guideCan a Furnace Leak Carbon Monoxide? How It Happens
Yes. How a gas furnace leaks carbon monoxide, the symptoms MDH lists, Minnesota's CO alarm law, steps to take when one sounds, and what a red tag means.
Read the guideWhy Is My Furnace Leaking Water? Causes by Where It Drips
Water under your furnace, even in summer? Find the source by where it drips: drain, pump, humidifier or AC coil, and what our $79 trip charge covers.
Read the guideFurnace Noises: What Each Sound Means, When to Shut It Off
Bang, squeal, scrape, rattle, hum, click or whistle: what each furnace noise means, whether it's safe to run, and when to call 612-429-3465.
Read the guideHow Long Does a Furnace Last in Minnesota?
Most gas furnaces last 15–20 years, per Carrier and Lennox. See why Minnesota winters add wear, the end-of-life signs and our $4,500–$9,500 replacement range.
Read the guideBest Furnace Brands for Minnesota Winters (2026)
Furnace brands for a Minnesota winter by tier: Carrier, Trane, Lennox, Rheem, Goodman and Amana, what matters more than the badge, and $4,500–$9,500 installs.
Read the guideCarrier vs Trane vs Lennox for a Minnesota Home
Carrier vs Trane vs Lennox for Minnesota homes: how the tiers line up, which controls lock you into one brand, and what to know about warranty registration.
Read the guideFrozen Condensate Line on a High-Efficiency Furnace
Furnace quit in a cold snap because the drain line froze? How to thaw it safely, stop it refreezing, and our $79 trip charge, waived with the repair.
Read the guideNo Heat in a Minnesota Winter: What to Check Before You Call
Furnace out on a cold Minnesota night? The checks to make in order, reading the blink code, keeping pipes safe while you wait, and when to call 612-429-3465.
Read the guideOutdoor Wood Boiler vs Gas Furnace in Minnesota
Is an outdoor wood boiler cheaper than a gas furnace in Minnesota? Fuel math per million BTU, daily labor, smoke rules, freeze risk and backup heat.
Read the guideOil to Natural Gas Conversion in Minnesota: Steps and Costs
Converting an oil furnace or boiler to natural gas in Minnesota: $6,000–$20,000 nationally, getting gas to the house, venting, the oil tank and hot water.
Read the guideHow HVAC Zoning Works, and Whether It Pays Off in Minnesota
HVAC zoning gives each floor its own thermostat and motorized dampers on one furnace and AC. HomeGuide puts a 2–3 zone retrofit at $1,700–$3,500 nationally.
Read the guideQuietest Furnaces for Minnesota Homes, and Why Ducts Matter
The quietest gas furnaces from Lennox, Carrier and Trane, the features that cut noise, and the duct fixes for a Minnesota home. 96–98% models: $6,500–$9,500.
Read the guideGas Line Installation Cost for a Furnace or Heater
A gas line for a furnace, garage heater or range runs $350–$2,000 nationally. How pipe is sized to the BTU load, and the permit and pressure-test steps.
Read the guidePrescott, WI Furnaces: Propane, Flooding and Wisconsin Rules
Furnace repair in Prescott, WI and nearby Pierce County towns: common no-heat causes, propane quirks, Wisconsin programs, and our $79 trip charge.
Read the guideFurnace Short Cycling: Time the Cycle, Then Find the Cause
A furnace that turns on and off too often tells you what's wrong by how long it runs. How to time a cycle, what it means, and when to call 612-429-3465.
Read the guideBryant Evolution vs Legacy Furnaces: What You Pay For
Bryant's Evolution 987M modulates; Legacy furnaces are single-stage. What that means in a Minnesota winter, how warranties compare, and where Preferred fits.
Read the guideCracked Heat Exchanger: Symptoms and How It's Confirmed
Signs of a cracked furnace heat exchanger, how a technician confirms it with a camera and CO readings, what to do after a red tag, and repair vs replace.
Read the guideBoiler Banging, Kettling or Gurgling: What Each Noise Means
Kettling, banging, gurgling or a grinding pump: what each boiler noise means in a hot-water or steam system, which checks are safe, and when to call.
Read the guideFurnace Limit Switch Tripping? What to Check First
Why a furnace high-limit switch keeps tripping, a symptom-to-cause table, the checks to do yourself, the order a technician follows, and what the fix costs.
Read the guideBest Garage Heater for a Minnesota Winter, by Type
Forced-air unit heater, infrared tube, electric or mini-split? How to pick garage heat for a Minnesota winter, what installs cost and the venting rules.
Read the guideLennox Furnaces Compared: Merit, Elite and Signature
Lennox Merit, Elite and Signature furnaces overlap more than the names suggest. Learn to decode a model number; our 96–98% AFUE installs run $6,500–$9,500.
Read the guideRadiant Floor Heat vs Baseboard in Minnesota
Radiant floor or hydronic baseboard for a Minnesota basement, addition or remodel: comfort, water temperature, boiler efficiency and what a retrofit involves.
Read the guideFurnace Burning Smell in Minneapolis: What Each Smell Means
Dust, hot plastic, rotten eggs or exhaust: what each furnace smell means, which mean shut it off now, and the basement causes common in Minneapolis homes.
Read the guideFrozen Furnace Vent Pipe? How to Clear It in Minnesota
Furnace quit in a cold snap? Learn how to clear an iced PVC vent safely and stop it from recurring. If it won't stay lit, call 612-429-3465.
Read the guidePropane Heating Costs for Rural Twin Cities-Area Homes
What propane really costs a Minnesota home per million BTU, how it compares to gas and heat pumps, and how the right furnace and fill plan cut gallons.
Read the guideTrane or Carrier Furnace? A Minnesota Buying Guide
Trane or Carrier furnace? How the lineups match up, warranty registration windows, quote checks and Minnesota install costs of $4,500–$9,500.
Read the guideBoiler vs Furnace: Which Fits Your Saint Paul Home?
Keep the boiler or switch to a furnace? How Saint Paul radiator homes and postwar houses decide, what each costs to replace, and how to add AC without ducts.
Read the guideFurnace Blowing Cold Air: What to Check, in Order
Cold air at the registers with the heat on? The order a technician checks, from fan setting to flame sensor and PVC pipes, and our $79 trip charge.
Read the guide96% vs 98% AFUE Furnace: Worth the Upgrade in Minnesota?
A 98% AFUE furnace saves only about 2% more gas than a 96% model. Our condensing furnaces run $6,500–$9,500 installed. See what the extra buys.
Read the guideFurnace Won't Ignite: Find Where the Startup Stops
Furnace clicking but not lighting? Follow a technician's startup sequence, from power and inducer to igniter, gas and flame sensor, then call 612-429-3465.
Read the guideHeating questions
What should I check before calling for furnace repair?
Make sure the thermostat is set to heat and above room temperature, the furnace switch and breaker are on, and the filter is not clogged. If you smell gas, leave the house and call your gas utility or 911 before anything else.
Contact Us
Heat out? AC quit? Call or send a request.