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Noises You Should Never Hear from Your Air Conditioner

Although air conditioners do make some “normal” noises during their operation caused by electronic and mechanical components, there are some noises you should never hear coming from your air conditioning system. As a southeast Michigan homeowner, you are probably used to certain ticks and sounds that aren’t problematic. However, there are certain sounds you should pay close attention to. Here is a list that may help you determine the possible problem before you call our skilled HVAC technicians.

Squealing Noise

A blower belt that is worn-out can cause a squealing noise at the indoor air handler or outdoor cabinet. If you schedule regular preventive maintenance, this problem can usually be avoided.

Screaming or Hissing

The compressor, located in the outdoor cabinet, is essentially the “heart” of your A/C system. When you notice a loud screaming or hissing noise coming from the compressor, it could potentially be a dangerous situation and may indicate a faulty high-pressure sensor. The compressor is responsible for extracting and releasing heat by pumping refrigerant between the evaporator and condenser coils. If you hear a screaming or hissing noise, call Haley Mechanical immediately.

Humming or Buzzing

A failed blower motor or capacitor can result in a humming or buzzing noise. If you hear this humming while your A/C system is running, it is likely a motor problem. If the system will not turn on, it is probably due to a failed capacitor. In either situation, give us a call.


A ticking or clicking noise may be noticed if there is an object lodged inside the fan assembly located in the outdoor cabinet. The blades of the fan may strike the object, causing the clicking noise. Make certain the air conditioner is turned off before you attempt to remove the object yourself. Pull out the disconnect plug, and shut the unit off at the thermostat.

Clamoring or Rattling of Vents

The air ducts deliver conditioned air into your home, and although the ducts are not an actual component of your air conditioning system, loose ducts can result in loss of conditioned air and increased energy costs. Rattling or clamoring noises coming from the vents typically indicate loose ducts; this can be remedied using metal tape.

Hearing other noises that don’t sound normal, or that you are not used to hearing? At Haley Mechanical, our job is to ensure SE Michigan homeowners enjoy a comfortable home and that your air conditioner is properly maintained so you can enjoy years of comfort and energy efficiency. Give us a call today!

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