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Triple O Heating, Cooling, Electrical & Plumbing Blog

Sounds That May Mean an Impending HVAC Catastrophe

The title of this post may sound a touch extreme, but if you find yourself in the middle of a heat wave with a malfunctioning air conditioning system, the word “catastrophe” will probably leap to your mind quickly. 

Fortunately, if you do have a busted AC or heater, you’re already in good hands because you’ve arrived here. 

But we’d also like to help you predict when you’ve got an HVAC system cruising for disaster. It’s much better to call us before you’ve got a heating or cooling emergency on your hands, after all!

Sounds Are One of the Best Warnings of Trouble

Of all the ways to early-detect HVAC issues, strange sounds are one of the easiest to pick up on. Air conditioning and heating systems make a standard set of noises when they operate, and when an odd noise interrupts, it’s often difficult to miss. 

Here are several common warnings sounds to listen for:

  • Hissing, Bubbling: If you have a refrigerant-based HVAC system (i.e. an AC or heat pump), these sounds often warn of refrigerant leaks. Hissing is gaseous refrigerant and bubbling is liquid refrigerant. Any loss of refrigerant is a major problem since it will not only impair the system’s performance, it will eventually lead to the compressor burning out. A burnt-out compressor usually means the whole system must be replaced. 
  • Shrieking, Grinding: Any HVAC system with motors—and that’s almost all of them—can make this sound when one or more of the motors starts to wear down its bearings or is burning out. Shrieking means the bearings are almost shot; if you catch this problem early enough, technicians can rescue the motor by replacing the bearings. Grinding means the motor is burning out, and will probably need to be replaced.
  • Loud and Persistent Clicking: Hearing clicking from an HVAC system is normal when it cycles down. This is the noise of the mechanical parts cooling down. If you hear loud clicking at other times and it happens frequently, then it might be due to a host of issues, such as electrical problems or a cracked heat exchanger. We recommend shutting down the HVAC system and calling for professionals to diagnose the problem.
  • Rattling: This might be as simple as a loose panel on the HVAC cabinet. But it often indicates parts that are loose or are coming loose. If securing the panel doesn’t stop the sound, call for technicians to investigate the source—loose components can rapidly lead to bigger problems.
  • Clanging: Any sound of metal-striking-metal is a big warning that something may be wrong in the blower assembly. (Any forced-air HVAC system like a furnace, AC, or heat pump has a blower.) The blower may be misaligned or a fan blade bent. If this is allowed to continue, it will inflict major damage to the blower housing and the blower assembly.

When in doubt, always shut off your HVAC system and call for licensed professionals to see what’s wrong. Most of these issues you can’t repair yourself, so you’ll need the pros eventually anyway. Get our team involved from the start—we handle all types of HVAC systems and provide heating and air conditioning repair in Rochester, NY.

Triple O Heating, Cooling, Electrical & Plumbing Is Your One-stop Shop for HVAC, Plumbing and Electrical. Call us when you think you’ve got an HVAC system that needs repairs. 

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