Kansas City winters are serious — temperatures regularly drop below 15°F, and a furnace failure is not just uncomfortable, it’s dangerous for pipes and for vulnerable family members. Most furnaces last 15–25 years. Here are the signs yours is approaching the end.
1. Your Furnace Is 15–20+ Years Old
Age alone isn’t disqualifying, but once a furnace crosses 15 years, parts become harder to source, efficiency drops, and failure risk rises sharply. If yours is older than 20 years, budget for replacement regardless of current performance.
2. Yellow or Flickering Pilot Flame
A healthy furnace burns with a steady blue flame. A yellow or orange flame means incomplete combustion — which can indicate a cracked heat exchanger or a carbon monoxide problem. If you see a yellow flame, call an HVAC technician and consider getting your CO detectors checked immediately.
3. Carbon Monoxide Detector Going Off
A CO detector alarm near your furnace is an emergency. Leave the house, call 911, and then call an HVAC technician. A cracked heat exchanger — common in aging furnaces — leaks CO into the living space. This is a replace-immediately situation, not a repair-and-see situation.
4. Unusual Noises: Banging, Popping, Rattling, or Squealing
Some furnace noise is normal. Loud banging at startup often means delayed ignition (gas buildup igniting at once). Rattling can be loose panels or a cracked heat exchanger. Squealing is usually a failing blower motor bearing. All of these warrant a technician visit.
5. Your Heating Bills Are Climbing Year Over Year
Aging furnaces lose efficiency — an older unit rated at 80% AFUE when new may actually be operating at 60–65% efficiency now. Pair that with rising gas costs and you’re paying significantly more to heat the same home. A modern high-efficiency furnace (95–98% AFUE) can cut your heating bill substantially.
6. Rooms at Different Temperatures or Poor Air Distribution
If some rooms are cold while others are overheated, the culprit might be a failing furnace that can’t maintain consistent airflow, deteriorating ductwork, or both. An HVAC technician can diagnose which it is.
7. Frequent Repairs Over the Past Two Years
One repair over two years is normal. Two or three in the same season is a sign the system is failing piece by piece. Total up what you’ve spent on repairs in the last two years — if it’s approaching $1,000–1,500 for a unit 15+ years old, replacement will be cheaper in the long run.
When to Act
Don’t wait for a cold snap to find out your furnace is done. If you’re seeing two or more of the signs above, schedule a pre-season inspection and honest assessment now.
Request a free assessment — we’ll connect you with a licensed Kansas City HVAC contractor who can tell you exactly what you’re working with.
Written & Reviewed By
HVAC Repair KC
All articles are written or reviewed by licensed HVAC technicians serving the KC metro. Content is updated as codes, pricing, and equipment evolve.