When the winter temperatures drop, your furnace becomes one of the most important systems in your home. But like any mechanical equipment, furnaces can develop problems some of which can pose safety risks or lead to costly breakdowns if ignored. Knowing the emergency warning signs can help you take action before small issues turn into major repairs or safety hazards. LV Heating & Cooling would like to highlight the top furnace warning signs you should never overlook.
Strange or Loud Noises
A healthy furnace runs quietly with a low hum. If you start hearing banging, screeching, rattling, or grinding sounds, something is wrong. These noises could indicate:
• A loose or broken component.
• A worn-out blower motor.
• Problems with the ignition system.
• Dirty burners or debris inside the furnace.
Don’t ignore strange sounds as they can quickly escalate into bigger, more expensive repairs if left unchecked.
A Burning or Unusual Smell
When you first turn on your furnace for the season, a mild burning dust smell is normal. However, persistent burning odors, or smells that resemble metal, rubber, or smoke, are serious red flags. These could point to:
• Electrical problems
• Overheating components
• A blocked vent or flue
If you ever smell gas or sulfur much like rotten eggs, leave your home immediately and call your gas company or emergency services. Gas leaks are extremely dangerous and require immediate attention.
Furnace Blowing Cold Air
If your furnace runs but only blows cold or lukewarm air, it is not just an inconvenience, it is a sign of a malfunction. Common causes include:
• A malfunctioning thermostat.
• A faulty ignitor or pilot light.
• A dirty flame sensor.
• A clogged air filter restricting airflow.
A professional inspection can identify and fix the problem before your system shuts down completely.
Frequent Cycling On and Off
If your furnace keeps turning on and off every few minutes, it is short cycling and it is more than just annoying. Short cycling puts strain on the system and can result from:
• A dirty air filter.
• An oversized furnace.
• A malfunctioning thermostat.
• A blocked exhaust vent.
Addressing the root cause early can prevent a total system failure and improve energy efficiency.
Yellow or Flickering Burner Flame
A healthy furnace flame should burn steady blue. If it is yellow, orange, or flickering, it may indicate incomplete combustion or a potential carbon monoxide leak. Carbon monoxide is a colorless, odorless gas that can be deadly. Turn off your furnace immediately and call an HVAC professional to inspect and repair the issue before restarting the system.
Water Leaking Around the Furnace
If you see water pooling near your furnace, it is likely from a clogged condensate drain line or a malfunctioning condensation pump. While this may seem minor, leaks can cause rust, mold growth, and electrical hazards if ignored.
Heating Inspections, Tune Ups, Repair, Replacement & More in Summerlin, North LV, Henderson, Enterprise, Paradise, Spring Valley, Sunrise Manor & Greater Las Vegas, NV
Ignoring furnace warning signs can lead to sudden breakdowns, costly repairs, or even health risks. If your system shows any of these red flags, turn it off and call a licensed HVAC technician right away. For emergency furnace repairs, contact LV Heating & Cooling today.
