Furnace Pre-Season Startup Checklist for Minnesota Homeowners

Start Your Furnace Season Right

The first cold snap of a Minnesota fall is not the time to discover your furnace has a problem. Running through a pre-season checklist in September or early October gives you time to order parts, schedule service, and avoid the emergency call surge that hits every November. This checklist covers what to check before you need heat.

Pre-Season Furnace Checklist

• Replace the air filter. A clean filter is the single most impactful maintenance step. Use a MERV 8–11 filter for most homes. See our filter guide for recommendations.
• Test your thermostat. Switch to heat mode, set it 5°F above current room temp, and confirm the furnace fires within 60 seconds. If not, check settings and batteries first, then troubleshoot further.
• Listen for unusual sounds. A properly functioning furnace should ignite cleanly and run quietly. Banging, squealing, grinding, or rattling indicate problems — see our guides on blower motors and ignitors.
• Check all supply and return registers. Ensure none are blocked by furniture or closed. Restricted airflow causes overheating and limit switch trips.
• Inspect the flue pipe. Check for disconnected sections, corrosion, or obstructions. Bird nests in flue caps are a common fall problem.
• Test CO detectors. Replace batteries and test all detectors. CO detector placement guide is in our CO safety guide.
• Check condensate drain (96% furnaces). High-efficiency furnaces produce condensate that must drain freely. See our condensate guide.
• Visually inspect the heat exchanger. Look for cracks, rust, or soot around the exchanger. Any concerns warrant professional inspection before running the furnace — see our heat exchanger guide.
• Schedule a professional tune-up. For furnaces over 5 years old, annual professional maintenance catches problems visual inspection misses. See our tune-up guide.

If Your Furnace Fails the Checklist

If your furnace is over 15–20 years old and showing multiple issues, replacement is often more economical than continued repair. A new Goodman from Furnace Direct delivers 96% AFUE efficiency at factory-direct pricing — use our buying guide to evaluate your options before the heating season peaks.