Your furnace is designed to run quietly in the background, providing steady heat without drawing attention. So when it suddenly starts making loud or unusual noises, it is a clear sign something is not right. Ignoring those sounds could lead to costly repairs or even safety hazards. LV Heating & Cooling would like to share a guide to the most common furnace noises, what causes them, and what you can do about it.
Banging or Popping Furnace Noises
Loud bangs or pops when your furnace starts up are often caused by a delayed ignition of gas in the combustion chamber. Dirt on burners can delay the gas ignition, creating a small explosion when it finally lights. Another possible cause is the metal ductwork expanding and contracting as it heats up. What you should do:
• Have a professional clean and inspect the burners.
• Make sure your ducts are properly sized and insulated.
• If the sound is severe or frequent, shut off your furnace and call an HVAC technician immediately, as delayed ignition can be dangerous.
Screeching or Squealing Furnace Sounds
A high-pitched squeal usually comes from a worn-out or loose blower belt or motor bearings in need of lubrication. What you need to do:
• Turn off your furnace and check the blower belt, if you are comfortable doing so.
• Schedule a tune-up a technician can replace belts, lubricate parts, and check motor bearings.
Rattling or Clanking Furnace Noises
Rattling noises can mean loose screws, panels, or ducts. If the rattling is more like clanking, it could be a broken or loose part inside the blower assembly. When you hear these noises you should:
• Make sure all panels on the furnace are tightly secured.
• If the noise persists, call a professional to check internal components before they fail completely.
Whistling Furnace Sounds
A whistling furnace often means restricted airflow. This may happen because of a clogged air filter, blocked vents, or gaps in the ductwork. When you hear whistling you need to:
• Replace or clean your air filter.
• Check all supply and return vents for obstructions.
• Have a technician inspect your ducts for leaks or blockages.
Humming or Buzzing Furnace Noises
A low humming noise is normal, but a loud or persistent buzz can indicate electrical issues with the blower motor, capacitor, or transformer. What to Do when you hear a bumming or buzzing noise:
• Turn off the furnace and call an HVAC technician to diagnose the electrical components.
• Do not attempt electrical repairs yourself.
When to Call a Professional Heating Contractor
While some noises can be fixed with simple maintenance like replacing filters or tightening panels, many are signs of mechanical or safety issues. If you are unsure of the cause, especially with banging, burning smells, or electrical buzzing, shut down your furnace and call a qualified HVAC technician right away.
Heating Inspections, Tune Ups, Repair, Replacement & More in Summerlin, North LV, Henderson, Enterprise, Paradise, Spring Valley, Sunrise Manor & Greater Las Vegas, NV
Strange furnace noises are more than just an annoyance they are a warning. Addressing them early can prevent breakdowns, lower repair costs, and keep your home safe. Regular maintenance and inspections by a professional will also help catch these issues before they start. For help dealing with strange furnace noises, contact LV Heating & Cooling and schedule our services today!
