Switching From AC to Heat: How to Transition Your HVAC System Safely This Fall
During this transitional time, many homeowners have questions about what they can safely handle themselves and when it’s wiser to call a professional. Patriot Air has served Central Ohio since 2004, providing timely furnace maintenance in Columbus, OH, and nearby communities.
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When Should You Switch from AC to Heat in Columbus?
Knowing when to turn on the heat in Ohio can be confusing, especially during those sunny autumn weeks when the weather can’t seem to make up its mind. As a rule, it’s time to switch from AC to heat when overnight lows consistently stay in the 40s to 50s, which usually happens sometime around mid-October in the greater Columbus region.
If your thermostat constantly bounces between cooling and heating to keep up with warm afternoons, chilly evenings and frigid nights, it will force your HVAC system to work harder than it needs to. To avoid that flipflop, try using your thermostat’s AUTO mode or setting your heating and cooling setpoints a few degrees apart. That way, your system will only switch modes when it’s strictly necessary, protecting your equipment and keeping your home comfortable as the season changes.
How to Safely Transition Your HVAC System from Cooling to Heating
A safe fall HVAC transition is the best way to protect your equipment from damage and avoid a no-heat emergency when temperatures drop. Before turning on your furnace for the first time this season, walk through these steps to prepare everything for colder weather. And if you have any questions, we’re always here to help with our heating services in Columbus.
Replace Your Air Filter
Your air filter may have become packed with dust, pollen, pet hair and other debris after working tirelessly for you all summer. Clogged filters restrict airflow, creating headaches you can prevent by proactively scheduling your professional furnace tuneup in Columbus.
Our experienced team recommends checking and replacing your filter monthly to save money on your energy bills and ensure your HVAC equipment works smoothly. Kicking off the heating season with a clean, fresh filter will also improve your indoor air quality, which you’ll appreciate when you and your family hunker down in your cozy house to stay out of Ohio’s winter weather.
Test Your Carbon Monoxide and Smoke Detectors
Natural gas furnaces produce heat through combustion, making carbon monoxide detectors a nonnegotiable safety measure. Early fall is your ideal time to test every CO and smoke detector in your home, replace dead batteries and confirm each unit is less than 10 years old before heating season begins.
Clear the Area Around Your Furnace
Adequate airflow ensures your HVAC system starts smoothly and heats evenly, and it starts with giving your furnace the elbow room it needs to warm every room in your house. Remove storage boxes, paint cans, cleaning supplies and any flammable items from around the unit. Then, walk through your home and make sure furniture, curtains and rugs aren’t blocking your vents or return grilles.
Switch Your Thermostat to Heat Mode
Transitioning your thermostat correctly prevents strain on the system, so you can switch modes without causing unnecessary wear.
- Switch from COOL to OFF to HEAT.
- Set a comfortable starting temperature—68 degrees is a good baseline.
- Check the fan setting. AUTO is best for heating mode.
- If you have a heat pump, set it to HEAT, not EM HEAT.
Run a Test Cycle Before It Gets Cold
Turn on your heat during a mild day and let your furnace or heat pump run through a full cycle. Watch for burning smells that last longer than an hour, unusual noises, a slower-than-usual startup or cold air blowing from your vents. Identifying these issues before you need to rely on your heater daily will provide peace of mind.
Don’t Forget the Outdoor Unit
If you have a heat pump, clear leaves, sticks and debris from around the outdoor condenser. Adequate airflow keeps the system efficient and prevents strain when temperatures drop.
Is It Normal for Your Furnace to Smell When You First Turn It On?
Dust collects on your heat exchanger when it sits unused all summer, which leads to a characteristic furnace burning smell when first turned on. This odor typically lasts anywhere from a few minutes to about an hour and usually isn’t a cause for concern. However, persistent sharp or chemical odors merit professional attention.
Never ignore burning plastic or electrical smells, which can result from overheating wiring or failing components. If you catch a whiff of sulfur or rotten eggs, immediately turn off your furnace, evacuate your property and call Columbia Gas and 911 from outside to report a potential gas leak.
Tips for Heat Pump and Geothermal Owners
Your fall HVAC transition will look slightly different if you use a heat pump. These energy-efficient appliances switch from cooling to heating on the same system, with no separate appliance to turn on. As temperatures drop, it helps to understand how your heat pump works, so you know when you need to call us for heat pump services in Columbus.
Most heat pumps have two backup modes. Auxiliary heat turns on automatically during frigid weather when the system needs help reaching your set temperature. In contrast, emergency heat is a manual setting that bypasses the heat pump entirely and uses the backup heat source alone. EM Heat should never be your everyday heating mode; it’s only for situations where the outdoor unit is malfunctioning or frozen. If you’re unsure whether your system is switching correctly, Patriot Air’s team will be happy to clean, calibrate and fine-tune your equipment.
Your heat pump may also enter defrost mode in winter if frost builds up on the outdoor unit. During this cycle, you might see rising steam, hear an unfamiliar sound or notice the outdoor fan pause. All of this is normal and means the system is protecting itself so it can continue heating efficiently.
Because heat pumps run year-round, you should never cover your outdoor unit. Covers trap moisture, restrict airflow and can cause damage. Instead, keep the area around the unit clear. Snow, ice, leaves and windblown debris can block airflow, so make a habit of checking the unit after storms and maintaining a couple of feet of open space around it.
What About Geothermal?
Geothermal HVAC is one of the most environmentally friendly, stable heating options available. These systems don’t have an outdoor condenser to winterize, and the ground loop automatically adjusts to seasonal temperature swings. However, your indoor unit will still benefit from regular filter changes and an annual check to keep everything in good condition.
Patriot Air installs and maintains complete Water Furnace geothermal heating and cooling systems in residential communities throughout Central Ohio. Trusting your geothermal heating in Columbus to our certified team is a valuable investment in your home’s energy efficiency that gives you access to our team’s specialized expertise.
Why a Fall Furnace Tuneup Makes the Switch Easier
After months of running in AC mode, your HVAC system will benefit from a professional check before it tackles the demands of Ohio’s colder weather. When performing fall furnace maintenance, Patriot Air’s well-trained, NATE-certified technicians can diagnose issues on any make or model, especially Lennox, Trane and Water Furnace. Every service visit begins with a complimentary consultation and transparent estimates to eliminate surprises.
When performing a fall heating tuneup, we’ll identify worn parts, airflow issues and other early signs of trouble before they leave you shivering without heat on a cold November night. We will also clean and adjust your furnace or heat pump’s internal components to prepare it for the season ahead. Patriot Air makes it simple to stay ahead of these seasonal needs with our comprehensive HVAC maintenance plans.
Members receive priority scheduling, same-day service availability, no diagnostic charges and a 90-day trial period with the flexibility to cancel anytime. These maintenance plan benefits will inspire confidence that your heating system will be reliable from the first cold snap of autumn to the return of spring weather.
FAQs About Switching from AC to Heat
Is it bad to switch from AC to heat on the same day?
You may need to switch modes daily in early autumn to keep pace with Central Ohio’s dramatic temperature swings. However, you’ll want to avoid constant adjustments, which will strain your system. Using AUTO mode or setting your heating and cooling temperatures a few degrees apart will prevent unnecessary cycling.
Why does my house smell like burning when I turn on the heat?
It’s normal to notice a dusty, burning smell the first time you transition between air conditioning and heating. If you smell burning plastic or electrical odors that don’t go away, turn off your HVAC system and call our professional team.
Should I cover my AC unit in the winter?
If you have an AC-only outdoor unit, adding a breathable top cover to keep leaves out is fine, but you shouldn’t completely enclose the unit because it traps moisture and causes corrosion. And never cover a heat pump, which needs open airflow in every season to run efficiently year-round.
What temperature should I set my thermostat in the fall?
Most homeowners start around 68 degrees in heating season to balance comfort and efficiency. If the forecast calls for a significant day-to-night swing, try using AUTO mode or setting heating and cooling temperatures a few degrees apart to prevent constant cycling.
How often should I get my furnace or heat pump serviced?
Once a year is the standard recommendation. A well-timed, proactive fall tuneup is the quickest, safest way to welcome heating season. Patriot Air’s maintenance plans make this easy with scheduled visits, priority service and no diagnostic fees while enrolled.
Why is my heat pump covered in frost or giving off steam in the winter?
By design, heat pumps enter defrost mode when frost builds up on the outdoor unit. Don’t worry if you see steam, hear a change in sound or notice the fan pause briefly. These signs indicate your system is melting frost so it can continue heating efficiently.
Do geothermal systems need a seasonal changeover?
No. Geothermal systems don’t have an outdoor condenser, and the ground loop handles seasonal temperature changes automatically. The indoor unit still needs regular filter changes and an annual check, but it won’t require additional winterization.
Get Your Home Ready for Winter with Patriot Air
Your fall HVAC transition shouldn’t be stressful. Knowing how to switch your thermostat from cool to heat, replacing your air filter and running a quick test cycle will let you welcome the new season with a clear conscience. And if you want extra reassurance before winter settles in, a professional tuneup is a hassle-free way to get ahead of all your heating needs.
Patriot Air Comfort Systems has served Columbus and Central Ohio since 2004 from our Groveport headquarters, dispatching our trained techs to cities throughout our broad service area, including Grove City, Dublin, Hilliard, Westerville, Gahanna, Pickerington and Canal Winchester. If you’re ready to prepare your home for winter, call 614-577-1577 or request service online to schedule your furnace, heat pump or geothermal tuneup today.