Your late fall Furnace Game Plan: Quick Wins to Cut Bills and Prevent Breakdowns
October and November in Central Iowa is that awkward moment when your thermostat goes from “maybe later” to “please save me.” If you want a cozy home without surprise repair bills, a little prep now pays off through the first real cold snap. Here is your fast, practical checklist from Obsidian Heating & Cooling to help homeowners in Ankeny, Des Moines, West Des Moines, Urbandale, Johnston, Waukee, Altoona, and nearby stay warm, safe, and efficient.
1) Swap Your Filter Before the First Cold Blast
A dirty filter is the easiest way to waste money and stress your furnace. It restricts airflow, drives up static pressure, and can cause short cycling or overheating.
What to do
Check your filter size and type. If in doubt, snap a pic of the label and keep it in your phone.
Replace 1-inch filters monthly during heavy use. Thicker media (3–5 inch) can last longer, but inspect monthly.
Choose a MERV rating that balances air quality and airflow. If you have a high-MERV filter and your system seems loud or weak at the vents, step down a notch.
Pro tip
Write the change date on the filter frame and set a calendar reminder. Future you will be grateful.
2) Open Every Supply and Return Vent
Closing vents in unused rooms does not save money. It increases static pressure and makes the furnace work harder. That means noisy ducts, higher bills, and uneven temperatures.
What to do
Open supply registers fully and clear two feet around each vent.
Check returns behind furniture, curtains, and holiday décor.
If a room always runs cold, note it. The problem is usually airflow or insulation, not the thermostat setting.
3) Set a Smart Thermostat Strategy
Small changes beat big swings. Large setbacks can make your furnace work harder during recovery on a windy, ten-degree morning.
What to do
Aim for small, predictable set backs overnight and while you are out. Think 2–4 degrees, not 8–10.
Use a smart thermostat to stage heat gently and maintain more even temperatures.
If you have a two-stage or variable-speed furnace, pair it with a compatible thermostat to unlock smoother runtimes and better comfort.
4) Seal the Simple Leaks First
Warm air is expensive. Don’t let it slip out through easy gaps.
What to do
Install fresh door sweeps at the front and garage-to-house doors.
Weatherstrip leaky exterior doors.
Close the fireplace damper when not in use.
If you can feel air at window and trim joints, a bead of paintable caulk goes a long way.
Bonus
Close blinds and curtains at night for an instant thermal blanket. Open them during sunny afternoons.
5) Give Your Basement and Utility Room a Quick Pass
Your furnace needs room to breathe. Storage that creeps too close can restrict combustion air and service access.
What to do
Clear 3 feet of space around the furnace and water heater.
Make sure the filter door closes tightly.
Look for water around the furnace base. It can indicate a clogged condensate line on high-efficiency models.
6) Listen for “Spooky” Noises and Fix Them Early
Bangs, squeals, and whistles are not normal background music. They are early warning lights.
What to do
Note what you hear and when: startup, shutdown, or constant.
Replace the filter and open vents first. If the sound persists, call a pro before the next deep freeze.
If you missed it, check out our post on the 7 spooky HVAC noises and what they usually mean.
7) Schedule a Pre-Winter Tune-Up
A professional tune-up catches small issues before they turn into emergency calls at 2 a.m. It also verifies safe operation, especially important for gas furnaces.
What we check during a tune-up
Combustion analysis and venting safety
Flame sensor, igniter, burners, inducer motor
Blower motor, capacitor, wheel cleanliness and balance
Static pressure and basic airflow health
Electrical connections and control board diagnostics
Thermostat calibration and staging setup
Filter fitment and general system cleanliness
Time investment
Plan on about 45 to 75 minutes for a thorough visit, depending on system condition.
8) Consider Easy Comfort Upgrades
If your system is healthy but your home still feels uneven, a few targeted upgrades can make a big difference.
Ideas to explore
Media filter cabinet for better airflow and fewer filter changes
Return air additions in closed-off rooms or upper floors
Variable-speed blower or two-stage furnace for steadier heat
Zoning for two-story homes with big temperature differences
Smart thermostat with room sensors to address hot/cold spots
We can price these options alongside a tune-up or furnace replacement so you can see the comfort and cost impact.
9) Safety First: Carbon Monoxide & Smoke Detectors
Replace batteries, test alarms, and make sure at least one CO detector is near sleeping areas and another near the utility room.
If your CO alarm ever sounds
Ventilate immediately and call a professional. Do not try to restart the furnace until it has been inspected.
10) Know When It Is Time to Talk Replacement
If your furnace is 15 to 20 years old, needs frequent furnace repairs, or struggles to reach setpoint, you may be paying more to keep an old system limping along than you would with a right-sized, high-efficiency replacement.
What we do differently
Run a Manual J load calculation
Check duct static pressure and returns
Show clear, no-pressure options with expected operating costs
Help you navigate available rebates and financing
Your November Action Plan
Replace the filter and open every vent.
Dial in smart, modest thermostat schedules.
Weatherstrip doors and add door sweeps.
Clear space around the furnace and check for moisture.
Book a tune-up before the first truly cold week.
Ask us about airflow and comfort upgrades if you still have hot and cold zones.
Ready for a warm, worry-free winter?
If you are in Ankeny, Des Moines, West Des Moines, Johnston, Urbandale, Waukee, Altoona, or a nearby community, Obsidian Heating & Cooling can get you set before the deep freeze hits. Book a pre-winter tune-up, schedule a furnace repair, or request a right-sized furnace installation estimate today.
Your future self, wrapped in a comfy blanket, says thanks.
