Strange noises coming from your AC aren’t just an inconvenience; they are signs that something is seriously wrong with your system. Here are the top air conditioning noises you should not ignore.
Buzzing Noises
Buzzing noises from your AC could mean two things: you either have an electrical or mechanical issue. Electrical issues include electrical acing, faulty relay switch, damaged circuit breaker, or malfunctioning capacitor. Electrical acing is when electricity jumps from one connection to another when there’s a gap along its pathway. It is caused by damaged wiring, electrical overload, or environmental conditions such as excessive moisture or debris.
The relay switch controls the flow of electricity to the compressor. It often malfunctions after power surges or outages. The capacitor, on the other hand, stores and releases electrical energy to your AC. It provides the initial surge of power needed to start the fan motors and compressor. Capacitors become faulty and produce a buzzing sound due to overheating, incorrect voltage, electrical overload, or manufacturing defects.
Mechanical issues could stem from loose or unbalanced fan blades, failing motors, or dirty condenser coils. AC fans become loose or unbalanced due to wear and tear, debris accumulation, or damage to the blades themselves. AC motor failures can stem from electrical faults, overheating, or excessive vibrations.
Dirt and debris often accumulate on the condenser coils. When the buildup is excessive, the grime can act as an insulator, restricting airflow across the condenser coils responsible for expelling heat. As a result, the condenser will have to work harder to cool. This strain can cause the system to overheat, resulting in buzzing noises.
Clicking Sounds
Repetitive clicking coming from outside the house could mean the compressor may have a loose bolt, wire, or refrigerant tube. If the sound is coming from the indoor unit, it is likely that fan blades are hitting an object or obstruction as they spin. This type of clicking noise starts slow, gradually increases in frequency, and eventually becomes persistent. If left unchecked, the repeated impact could damage the fan blades or the surrounding components. It’s crucial to turn off the AC and call a technician for professional AC repairs.
If the clicking sound comes on only at startup and shutdown, the relay switch that controls the compressor may be the culprit. The relay switch is responsible for transmitting electrical signals to turn the compressor on and off. It produces clicking noises when faulty.
If the AC clicks when you turn it on but it doesn’t run, there could be a problem with the controls. A faulty thermostat might fail to send the correct signals to the AC unit, preventing it from starting properly. Other potential issues include a damaged control board, a bad capacitor, loose or corroded wiring, or a tripped safety switch.
Banging Sounds
Banging, clanking, clanging, or slamming sounds from your AC system could be caused by an unbalanced blower, a loose part in the compressor, a dirty filter, or trapped debris in the outdoor unit. Lack of routine maintenance, particularly neglecting filter changes and indoor AC cleaning, allows dirt, debris, and pet hair to accumulate on the blower wheel, leading to an imbalance that produces loud, disruptive banging noises. The imbalance can strain the motor and other components, leading to complete system breakdown.
A loose screw, bolt, flywheel, clamp, belt guard, or other accessory in the compressor can also cause loud clanging or slamming sounds. These items might become loose because of improper mounting, wear and tear, or excessive vibrations during operation.
Debris, like leaves, twigs, grass clippings, and dust, can become trapped in the outdoor unit, potentially clogging vents and coils. This obstruction limits airflow, causing the system to overheat or work harder to maintain cooling efficiency. As the system struggles, its parts can break, loosen, or vibrate excessively, resulting in loud banging sounds.
Hissing Sounds
There are several reasons why ACs produce hissing sounds. The first is a refrigerant leak. The refrigerant in your system is under pressure. That pressure is needed to help it transfer heat efficiently and effectively as your AC runs. When something damages its coils or lines, it creates an opening through which the refrigerant forcefully escapes, producing a distinct hissing noise. This sound can be accompanied by bubbling or gurgling noises.
It’s important to note that the refrigerant is a very dangerous compound. When inhaled, it can cause irritation of the respiratory system, dizziness, headaches, and nausea. Longer or higher concentration exposure can lead to vision loss, severe stomach pain, loss of consciousness, breathing difficulties, seizures, and coma. Therefore, turn off your system and call for emergency repairs.
The second cause of hissing sounds is leaky ducts. Ducts transport conditioned air from the indoor AC unit to various supply vents in your home. When there are gaps, cracks, or loose connections in the ductwork, air can escape under pressure, producing a hissing noise.
A damaged compressor can also produce hissing sounds. A worn-out compressor can cause irregular airflow and pressure differentials within the system. When the pressure builds up too high, it can escape, producing a high-pitched hissing noise.
Chirping Sounds
Chirping sounds indicate that the motor bearings in your AC are dry and rubbing against other components. This friction typically occurs due to a lack of lubrication or wear and tear over time.
How To Deal With Weird AC Sounds
Weird AC sounds are a by-product of an underlying issue within your system. In other words, your system is already damaged, and continuing to operate it could worsen the problem or lead to a complete breakdown. Therefore, turn off your AC immediately and keep a safe distance, especially for hissing, gurgling, or bubbling noises.
Do not attempt DIY repairs. AC systems contain high-voltage electricity and refrigerants that can be dangerous if mishandled. You might also misdiagnose the problems, leading to further damage or unnecessary costs. More importantly, you’ll void your warranty.
Instead, call a licensed and experienced HVAC technician to inspect and repair your AC. They have the expertise and tools needed to identify the root cause of the issue and resolve it safely and effectively.
Preventing AC Noises
To prevent AC system issues, start by replacing your air filters after every two to three months. Most AC problems stem from poor airflow caused by clogged or dirty filters. For example, blocked filters will cause the fan motor to strain to pull air to the indoor unit for conditioning. This strain quickly wears out the bearings and fan motors, leading to chirping noises. The compressor also suffers from limited airflow within the system. It will work harder to maintain the desired cooling performance, causing overheating and potentially leading to hissing or banging sounds.
Additionally, adhere to your professional AC maintenance schedule. During a service call, your HVAC technician will clean the system, lubricate moving parts, check the refrigerant level and safety systems, and alert you to worn-out components needing replacement.
Your Local AC Resource
Turn to our experts at Affordable Air for professional assistance. With over 20 years of experience, we are the leading choice for AC repairs in Garland, TX. Our highly trained technicians will help you identify the type of noise your system is making and guide you on the next steps to take. Besides repairs, you can also rely on us for AC maintenance or replacement. For AC repair in Garland, call us at Affordable Air today.
