Furnace Noise: So What Does That Cracking, Popping Or Banging Mean?

Furnace Noise: So What Does That Cracking, Popping Or Banging Mean?

Mar 22, 2012
Technician Looking Over A Gas Furnace

The familiar sounds of the furnace moving warm air through the system can be reassuring and soothing on a cold winter day. We expect to hear the blower motor pushing air through the ductwork and out the vents, the burners switching off and on, and small noises as the components all work together to make our home comfortable. However, unexpected furnace noise can be a sign of trouble. If your furnace starts making loud noises, more frequent noises or noises you’ve never heard before, it could mean an impending breakdown or a developing danger.

Furnace Booms And Popping Sounds

Loud booms, sharp pops and similar sounds can mean a dangerous buildup of flammable gas in the system. These noises can literally be small explosions as built-up gas ignites and burns away when your furnace’s burner comes on. This can be caused by dirty or clogged burners. Contact an HVAC professional to fix this problem immediately. The problem could lead to a serious fire or large explosion.

Furnace Rattling

Rattling noises within your furnace usually means something is loose or hasn’t been tightened or closed properly. Components may need to be secured, or loose bolts or screws may need to be tightened. If doors or panels aren’t closed tightly, they might tap repeatedly against adjoining pieces of metal. Loose or unsecured ductwork can also cause rattling noises.

Furnace Clicking

Unexplained clicks can be caused by a dirty or malfunctioning flame sensor, the device that detects whether the fuel has been ignited. Clicking sounds can also be caused by faulty igniters.

Furnace Squealing Or Grinding

Squealing sounds usually come from loose or slipping belts, such as the one on the blower motor. The blower motor can also produce grinding sounds if the bearings are wearing out. If the motor is grinding, it usually means it will have to be replaced soon.

Rinaldi’s Air Conditioning has been providing reliable heating and air conditioning services to customers in Orlando and central Florida for more than 40 years. Contact us today for help with interpreting furnace noise.

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