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You know that first Michigan morning when you step outside and realize summer is officially over? There’s frost on the grass, your car windows need scraping, and suddenly, sipping your coffee on the porch isn’t quite as comfortable as it was a few days ago.
That’s a rough time to find out your furnace has other plans.
After having extended leave for months, it’s a good idea to give your heating system a little attention before you’re counting on it to keep the house warm every day. Checking it now, before that first frost comes out of left field, gives you time to spot any problems early.
And if your furnace needs a bit of maintenance, you’ll have time to get it taken care of before the colder weather settles in.
When Should You Get Your Furnace Ready for Winter?
You don’t need to wait until your lawn looks frosty to fire up your furnace for the first time. In fact, it’s better if you don’t. Giving it a test run in early fall gives you a chance to make sure everything is working before you actually need the heat.
This is also a good time to schedule your annual furnace maintenance. Ideally, you should have your furnace checked in the fall, before your furnace is expected to clock in for the next few months.
Mark Your Calendar!
Southeast Michigan usually sees its first freeze sometime in October. Try to give your furnace its first test run and take care of any maintenance before then, while you still have some wiggle room if something isn’t working quite right.
Your Pre-Frost Furnace Checklist
Before you ask your furnace to get back to work, spend a few minutes checking the basics. You don’t need to take anything apart or poke around inside the equipment (nor should you). Most of this preseason prep is doable without too much elbow grease:
- Replace or Check the Furnace Filter
Pull out your furnace filter and take a peek at it. If it’s coated in dust and debris, replace it before you start running the heat regularly. A grubby filter restricts airflow through the system, which can make your furnace work harder to keep the house comfortable.
This is something you should check every month and replace every three months (or more often if needed). It’s an easy task to forget when you’re outside all summer, so starting the heating season with a clean filter gives you a fresh baseline.
- Clear Vents, Returns, and the Area Around Your Furnace
Take a quick walk through the house and make sure your supply vents and return-air grilles haven’t been blocked by furniture, rugs, or anything else that migrated over the summer. Your furnace needs a clear path to move warm air through the house, so open all your vents too.
Check around the furnace itself next. Move boxes, cleaning supplies, and other stored items away from the equipment, especially anything flammable. That’ll keep the area safer and make sure your furnace is easy to access once the heating season begins.
- Check Your Thermostat
Before you blame the furnace for a chilly house, make sure the thermostat is ready for the heating season, too. Switch it from cooling to heating mode, replace the batteries if needed, and check any programmed schedules you may have changed during the summer.
Bump up the temperature a few degrees and listen for the furnace to kick on. If the thermostat doesn’t respond or the furnace never starts, you’ll know there’s something to sort out before the cold arrives.
- Test Your Carbon Monoxide Detectors
While you’re making your way around the house, press the test button on each of your carbon monoxide detectors. Replace any low batteries, and take a peek at the manufacturer’s label to make sure the detector hasn’t reached the end of its expected lifespan.
This is one check you don’t want to realize you skipped after the heating season is already underway.
If you have a fuel-burning furnace, your CO detectors can warn you if carbon monoxide is building up inside your house. And if that alarm does ever go off, get everyone outside and call 911 rather than sticking around to figure out where it’s coming from.
- Give Your Furnace a Test Run
Don’t make the first freezing night of the year your furnace’s first day back on the job. Pick a cooler fall morning, turn the thermostat up a few degrees, and let the furnace run through a full heating cycle.
As it runs, check a few vents to make sure warm air is coming through and pay attention to how the house feels. The furnace should start without much fuss, run steadily, and shut back off once the thermostat reaches the temperature you set.
If it struggles to start, shuts off too quickly, or runs without actually warming your house, you’ve got a problem on your hands (but you probably have time to fix it before the cold sets in).
- Listen, Look, and Smell for Anything Strange
While the furnace is running, stick around and keep your eyes (and ears and nose) peeled for anything funky.
Listen for banging, rattling, squealing, or other noises you don’t remember hearing last winter. Check whether the airflow feels unusually weak, and make sure the furnace doesn’t cycle repeatedly.
You might notice a bit of a dusty smell the first time you turn on the heat after the summer, and that’s pretty normal.
Now, if that smell sticks around or starts to smell more like burning plastic, electrical wiring, or gas, that’s a problem. Shut the system down and have it checked rather than seeing if it’ll go away on its own.
Should You Schedule a Furnace Tune-Up Before Winter?
Even if your furnace seems to start up and run without a hitch, fall is still a good time to get annual maintenance on the calendar. A professional tune-up goes beyond the handful of checks you can safely handle yourself.
Your HVAC technician will get into the parts of the furnace you shouldn’t be messing with yourself, checking things like the burners, electrical connections, system controls, and heat exchanger.
More importantly, they can see how everything is actually running after a long summer off. If a part is wearing out or something isn’t operating quite right, you’d probably rather know about it now than during the first cold snap of the year.
What Does a Furnace Tune-Up Cost?
On average, a furnace tune-up costs somewhere in the ballpark of $130 to $450. Most homeowners pay right around $280.
It’s a pretty predictable expense to work into your fall budget, though, like any HVAC service, the actual cost you pay can vary based on the specifics of your system and what it needs.
What If Your Furnace Doesn’t Work When You Test It?
So, you turned your furnace on and… nothing. Before you assume that your furnace had permanently retired, check these things:
| What to Check | What to Do |
| Thermostat | Make sure it’s set to “heat” and the temperature is set higher than the current room temperature. |
| Furnace switch | Check that the switch near your furnace hasn’t accidentally been flipped off. It often looks like a regular light switch. |
| Circuit breaker | Look for a tripped breaker in your electrical panel. If it trips again after you reset it, leave it off and call for service. |
| Air filter | Check for a heavily clogged filter that could be limiting airflow through the system. Replace it if it’s dirty. |
| Vents and returns | Make sure they’re open and that nothing is blocking airflow around the house. |
If you’ve checked all of that and the furnace still won’t cooperate, it’s a good time to call for an HVAC technician.
Frequently Asked Questions
Once those chilly Michigan mornings start showing up, your furnace quickly becomes part of the daily routine again. Here are answers to some of the questions we get most often at this time of year.
When should I turn my furnace on in Michigan?
There’s no specific date you have to wait for. Many Southeast Michigan homes start needing heat sometime in the fall as overnight temperatures drop, but comfort is really the deciding factor. Just make sure you test your furnace before you’re relying on it every day.
Is it normal for my furnace to smell the first time I turn it on?
A mild dusty smell can be normal the first time your furnace runs after sitting unused all summer. Dust that settled on the system can heat up and create an odor, but that should fade pretty fast.
If that smell sticks around, gets stronger, or smells like gas, burning plastic, or something electrical, turn the furnace off and have it checked.
How often should I change my furnace filter in the winter?
Check your furnace filter about once a month during the heating season and replace it when it’s dirty. Usually, that comes out to replacing it every three months or so, but you might need to change it sooner if you have pets, a busy household, or other sources of dust.
Do I need a furnace tune-up every year?
We recommend it, ideally before the heating season begins. A yearly appointment gives your technician a chance to clean and inspect the system, check that it’s working right, and take care of maintenance that goes beyond what you can do at home.
How long should I let my furnace run when I test it?
Give it enough time to complete a full heating cycle rather than turning it off as soon as you feel warm air. You want to see that it starts normally, heats to the correct temperature, and shuts itself off once it gets there.
Why is my furnace blowing cold air when I first turn it on?
Your furnace might blow cool air while the system starts up and the ductwork warms. If the air stays cold after the furnace has been running for several minutes, check your thermostat settings and filter.
Continued cold airflow can point to an ignition, burner, or other furnace problem that needs professional attention.
What temperature should I set my thermostat to in the winter?
Set your thermostat to a comfortable temperature while you’re home and awake, then lower it while you’re asleep or away to save energy. Keep it above 50 degrees Fahrenheit when you’re away, as that’ll help prevent pipes from freezing and bursting but still help you save energy.
Get Your Furnace Winter-Ready With Dynamic HVAC
If you haven’t tested your furnace or scheduled its annual maintenance yet, now’s a good time to do it before October brings its chilly weather. It’s a lot easier to deal with a furnace problem now than on a night when you really need the heat.
Dynamic HVAC is here to help make sure your furnace is ready for the cold. Give us a call to schedule your furnace service today.
Sources & References
- Angi – “How Much Does Furnace Repair Cost in Detroit, MI?”
Provides current furnace repair cost estimates for the Detroit area, including typical price ranges and factors that can affect the final repair cost.
https://www.angi.com/articles/how-much-does-common-furnace-repair-cost/mi/detroit - ENERGY STAR – “Homeowner’s Guide to ENERGY STAR Certified Homes”
Provides homeowner guidance on heating and cooling system operation and maintenance, including filter care and seasonal HVAC upkeep.
https://www.energystar.gov/ia/new_homes/downloads/ES_Homeowner_Manual.pdf?30ac-8a7a - National Weather Service Detroit/Pontiac – “First Fall Freeze”
Provides historical first-freeze data for Southeast Michigan communities, showing when temperatures typically reach 32 degrees in the fall.
https://www.weather.gov/dtx/firstFallfreeze - Trane – “Recommended Thermostat Settings for Summer, Winter, and Vacation”
Provides recommended thermostat settings for different seasons and explains how homeowners can adjust temperatures for comfort and energy savings.
https://www.trane.com/residential/en/resources/blog/recommended-thermostat-settings-summer-and-winter-vacation
