Is Your Noisy Air Conditioner a Cause for Concern?

Posted: 2023-09-07

Any equipment that produces more noise than it should is a cause for concern, and this includes your air conditioner. Just as coughing can indicate an issue with your respiratory system, a noisy AC is signaling that it requires attention.

Dealing with a noisy air conditioner is a common issue for homeowners, and for an HVAC company in Lino Lakes MN, often receives calls about it.


When operating correctly, your air conditioner should operate quietly, almost unnoticed. However, excessive noise suggests that a part may be loose or that there's a blockage affecting airflow.

Identifying the source of a noisy air conditioner can be challenging for an untrained individual, as it might require disassembling the system. To ensure safety, it's advisable to have a qualified technician inspect your AC unit.

Here are some common sounds you might hear from your AC and their potential causes:

  1. Banging:

    • Loose components in the compressor, such as the crankshaft, connecting rod, or piston pin, can cause loud banging or knocking noises. In some cases, this may necessitate compressor replacement or simply tightening a few screws.
    • An unbalanced blower fan located in the indoor part of the system can also produce banging sounds as it spins.
    • If it's neither the compressor nor the fan, it's possible that the compressor itself is loose, or internal parts within the blower are making contact. Such issues can be complex to repair and should be addressed by a trusted AC technician.
  2. Buzzing:

    • A buzzing sound from your AC can have various causes, including a faulty compressor. The compressor is responsible for pressurizing and cooling the refrigerant, and a buzzing noise could indicate compressor problems or improper electrical voltage in the outdoor unit.
    • AC units may also produce a buzzing sound if they become frozen, especially after prolonged operation. Turning off the unit and allowing it to defrost can resolve this issue. If the noise persists, it might be due to a refrigerant leak, which should be addressed by a professional.
    • Electrical issues, such as a faulty contactor relay switch or loose electrical connections, can also cause buzzing sounds. Neglecting these problems can lead to more serious issues, including electrical shorts.
  3. Squealing:

    • Squealing is typically heard in older air conditioners that use belts, as newer models utilize direct-drive motors without belts. When the belt in an older system starts to wear, it can slip and create a squealing noise. Replacing the belt resolves this issue.

Give Your AC the Care it Deserves

Whether your air conditioner is producing banging, buzzing, squealing, or any other type of noise, it's essential to have it inspected and repaired by a qualified AC professional. At Four Seasons Air Specialists, our technicians are factory-trained and certified to diagnose problems and implement appropriate solutions. Our goal is to ensure your AC operates as quietly as possible, providing you with peace of mind. We have been serving as your trusted Centerville AC repair company since 1974.