When should I do a pre-winter furnace check?

Late summer through early fall, before the first sustained cold weather and before service schedules fill up.

Why should I run the furnace before winter?

A test run reveals ignition problems, noises, weak airflow and unheated rooms while there is still time to schedule a normal appointment.

Do I need to clear snow from my furnace vents?

Yes, if your furnace vents through a sidewall. Snow and ice at the termination can restrict draft and cause the furnace to lock out.

Should I have the ducts cleaned every year?

Annual duct cleaning is rarely necessary. Filter changes, sealed connections and adequate return capacity matter far more for both airflow and air quality.

What if my furnace smells when I first run it?

A dusty burning smell during the first cycles of the season is normally summer dust burning off the heat exchanger and clears within a few hours. Persistent or electrical odors should be inspected.

Winter Furnace Checklist | Before the Cold Arrives

Winter Furnace Checklist

Fort Collins weather does not ease into winter. A warm October afternoon can turn into a hard freeze overnight, and that first real cold snap is when neglected furnaces fail.

Call now for a FREE QUOTE and for service availability. Please have your 5-digit ZIP code ready.

Run the furnace before you need it

The single most useful thing on this list is also the easiest. On a mild fall day, set the thermostat above room temperature and let the furnace complete two or three full cycles. Listen for unusual noises, confirm warm air reaches every room, and note how long it takes to respond.

Discovering a problem in September is a scheduled appointment. Discovering it in January is an emergency call during the busiest week of the year.

Filter and airflow

Replace the filter with the correct size and a rating your system can handle — see the furnace filter guide
Confirm the airflow arrow points toward the furnace
Open every supply register, including in rooms you do not use much
Clear furniture, rugs and storage away from return grilles
Vacuum register grilles and visible duct openings

Outside the house

Snow drifting against a sidewall vent is a genuinely common cause of mid-storm lockouts in Fort Collins, Timnath and Wellington. It is worth adding a check to your routine after heavy snowfall.

Locate sidewall intake and exhaust terminations and keep them clear of snow, ice and debris
Check that landscaping and mulch have not grown up around the terminations
For chimney-vented systems, look for visible damage or blockage at the flue
Make sure roof drainage does not send water across the vent area where it can freeze

Thermostat and controls

Replace thermostat batteries at the start of the season
Set the mode to HEAT and the fan to AUTO
Review or rebuild the schedule for the season ahead
Confirm a smart thermostat is online and configured for your equipment type
Verify the displayed temperature roughly matches a separate thermometer

Talk through your furnace problem

For service availability, please have your 5-digit ZIP code ready.

Call 970-638-2717Free Quote Request Furnace Service

Call now for a FREE QUOTE and for service availability. Please have your 5-digit ZIP code ready.

Safety items

Details on alarm placement and response are in carbon monoxide furnace safety.

Test every smoke and carbon monoxide alarm
Check CO alarm expiration dates, not just batteries
Clear stored items away from the furnace and combustion air openings
Remove flammable liquids from the furnace area
Confirm everyone in the household knows where the furnace service switch is

Schedule professional service early

Book a furnace tune-up before the rush. A pre-season visit measures the things you cannot — flame signal, capacitor values, static pressure, temperature rise — and catches the drift that turns into a February breakdown. If anything on your walkthrough seemed off, mention it specifically when you schedule.

Know your plan if heat fails

Save the number for furnace service, know where the service switch and breaker are, and have a plan for protecting plumbing if the house cools quickly. Our emergency furnace repair page walks through what to do while you wait.