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How do you know when you need an AC replacement in Arlington, VA? Keep reading for a list of noises that indicate AC issues or need for servicing.

Loud AC Noise, What Does it Mean?

Air conditioning noise is a common problem with any air conditioner. However, if you are experiencing this issue, it may be due to some problems that need to be addressed before you go for an expensive AC Installation in Alexandria, VA.

You should check the thermostat settings and ensure they are set at the correct temperature. Also, make sure the blower motor is functioning properly. If these things aren’t working correctly, call our professional HVAC technician to come out and inspect your system.

Types of Loud AC Noises & Their Causes

Air conditioning units can create a variety of different sounds while operating. Here we explain some common types of noise that occur in AC systems.

  • Clicking Noise: This noise occurs when the unit is running but not cooling properly. If the problem does not correct itself after a few days, call your local HVAC company.
  • Hissing: This type of noise may occur when a system is under high load. Whistling noise is usually accompanied by a hissing sound. When the unit starts up, it makes a whirring noise as the fans spin up.
  • Rattling Noise: Rattling noise is caused by loose parts rattling around inside the cabinet or ductwork. Loose wires, clamps, screws, bolts, nuts, or other loose objects can cause a rattling noise.
  • Buzzing: Buzzing noise is created by the blower motor spinning at high speeds. It could indicate that the blower motor bearings need replacing or that the belt connecting the blower motor to the fan has become worn out.
  • Clanking: This noise means that your AC unit has failed. It can happen if the compressor motor fails. If this happens, you should immediately call our professional HVAC technician to come out and check things over. You may want to consider AC replacement in Fairfax, VA.
  • Humming: If you hear a loud humming sound from your air conditioning unit, you probably hear the dreaded hum of a compressor failure. To fix this problem, you’ll need to replace the compressor, or if the problem worsens, you may have to consider AC replacement in Arlington, VA.
  • Whistling: A whistling noise indicates a fan failure. A fan failure can occur when the fan belt breaks or the bearings fail. Either way, the fan will not work properly, and you will notice a lot of dust coming out of the vents.

Common Reasons for Loud AC Noises

Many different things can cause a loud noise from your AC unit. Some common reasons are:

  • Dirty filter
  • Clogged vents
  • Damaged compressor
  • Poor wiring connections
  • Improperly installed fan blades
  • An improperly fixed or installed drain pan
  • Dust buildup around the condenser coils


If your air conditioner is making a loud noise, we can help! At AVS Heating & Air Conditioning, we offer fast service at affordable prices. Our technicians have years of experience working on all makes and models of air conditioning systems. We’re here to help. Contact us without any further delay!