Few things compare with stepping into a cool and quiet home after a hot summer day in Amarillo and the Texas Panhandle area. If your air conditioning suddenly sounds like a rattling old truck, however, it can be both frustrating and concerning. Most abnormal or loud AC noises stem from common and easily resolved causes — learn why your AC unit is loud, what specific noises mean, and how Frank’s Repair Plumbing HVAC team can help.
What Should a Normal AC Sound Like?
A properly functioning air conditioning unit should operate with a consistent and low-level hum that blends into the background. Modern high-efficiency models are designed to operate more quietly than older units.
Sounds are more noticeable the closer you are to the indoor AC unit or outdoor condenser. If your AC is running properly, you may hear:
- A soft whooshing from air moving through the vents.
- A gentle hum from the compressor and fan motor.
- A clicking sound when the unit turns on or off.
Average conversation levels are about 60 decibels, and most central AC units range from 19 to 50 decibels. If you have to raise your voice to be heard when your AC is running, it’s likely generating more noise than it should.
Reasons Why AC Is So Loud
Wear, airflow obstructions, loose components, and other problems are common sources of excessive AC noise. An air conditioner that needs repair runs inefficiently, which often results in higher energy consumption and electricity bills. Follow a regular maintenance schedule to save energy and prolong your unit’s lifespan.
Dirty air filter
A clogged air filter restricts airflow, forcing the blower motor to work harder and generate excessive noise.
Loose parts
Vibrations from your AC may loosen screws, panels, and other parts, eventually causing rattling or buzzing sounds.
Worn components
Bearings and motors inside AC systems require regular lubrication to maintain smooth operation. Without sufficient lubrication, friction between parts increases and causes various sounds and AC damage.
Blocked air ducts or vents
Dust, pet hair, mold, and other debris may block your ductwork and restrict airflow. In severe cases, airflow obstruction may result in pressure imbalances within the system, causing the ductwork to expand and contract noisily as the AC cycles on and off.
Malfunctioning blower motor
A failing blower motor may produce various sounds depending on the nature of its breakdown. For example, worn bearings or belts may create high-pitched squealing, while electrical issues may produce persistent buzzing sounds.
Refrigerant leaks
A refrigerant leak can cause a bubbling or hissing sound, typically near the evaporator coil or refrigerant lines.
What Does a Bad AC Sound Like?
Abnormal or persistent air conditioner noises usually signal underlying problems that require professional AC repair or maintenance. Our expert and personable team at Frank’s Repair Plumbing can thoroughly inspect your system, troubleshoot noises, and restore proper AC function.
Review these common noises associated with AC troubles:
Banging from the compressor
Banging or clanking noises usually indicate broken parts within the compressor unit, such as loose piston pins or broken connector rods. Imbalanced fan blades and loose parts may also collide. These mechanical issues can become more severe and potentially cause compressor failure, which requires either emergency AC repair or premature compressor replacement.
Noisy condenser unit
If the outdoor AC unit makes loud noises while running, potential causes include a failing fan motor, a loose compressor component, or a blocked coil restricting airflow. Dirty components may likewise cause high pressure in the condenser unit, which can cause abnormal sounds.
Bubbling or gurgling leaks
Bubbling or gurgling sounds typically indicate fluid-related problems. A clogged condensate drain can cause water backups, which can increase the risk of mold growth and water damage.
When refrigerant levels are low or leaking, AC cooling power suffers, causing long cycles, higher energy bills, and increased strain on the compressor. If neglected, low refrigerant levels can eventually cause the system to overheat and fail. A refrigerant leak may also cause the evaporator coil to freeze, which then thaws and leaks water around the AC unit.
Buzzing
Buzzing noises can stem from multiple issues, including loose or unbalanced fan blades and electrical issues in the compressor. These units are also equipped with rubber isolation feet, which absorb shock to prevent noise and vibration. If they deteriorate, the compressor may vibrate against its base, causing further damage.
Clicking
Clicking is common when the AC unit starts but shouldn’t continue throughout the cycle. Continuous or irregular clicking may indicate a malfunctioning thermostat or electrical relay issue.
High-pitched vibrating
Airflow obstructions commonly cause high-pitched vibrating sounds. Blocked or dirty air vents, collapsed ductwork, or excessive debris inside the ducts can create turbulence and vibrations as the air forces through restricted pathways.
Hissing
While hissing from your AC could mean there’s a Western Diamondback rattlesnake trapped in your unit, it’s more likely an air duct leak. Leaks from ductwork damage or poor sealing cause energy loss, inefficiency, and HVAC system strain.
Humming contactor relay switch
A persistent humming noise may point to a faulty contactor relay switch, which helps regulate power to the compressor. Without repair, this issue may prevent the compressor from starting and result in system failure.
Rattling debris
Loose dirt, leaves, sticks, and other debris can accumulate on your outdoor condenser unit. Obstructions from debris in the fan blades may contribute to mechanical stress and system damage.
Screeching fan motor and bearings
A metal-on-metal screeching sound from the inside unit indicates insufficiently lubricated or worn-out bearings. If the sound comes from the outdoor unit, you may have a damaged fan motor or loose fan belt. If the screeching only lasts about 10 to 15 seconds when your AC turns on, the condenser may have high pressure.
Why Is the New AC So Loud Inside the House?
If your new AC is louder than expected, these reasons may be to blame:
- Improper installation
- Incorrect sizing
- High static pressure in ductwork
- Loud air handler or blower
- Poor insulation
How To Fix a Loud Air Conditioner
Routine maintenance and minor adjustments can resolve many AC noise concerns. Try these DIY fixes or preventative measures:
- Check for and tighten loose panels and screws.
- Inspect the air filter and replace it if necessary.
- If your unit has adjustable settings, try lowering the fan speed.
- Keep vents open and unobstructed, and check ductwork for gaps or damage.
- Inspect and clean the condenser unit.
More complex problems, such as refrigerant leaks, blower fan motor malfunctions, and ductwork layout, require the advanced knowledge and skills of a professional HVAC technician. If your troubleshooting doesn’t resolve strange or loud AC sounds, a licensed HVAC technician from Frank’s Repair Plumbing can help. Our expert technicians perform a multi-point inspection, tackle necessary cleaning, and take care of any repairs.
Enjoy extra perks and join our Diamond Club to help keep your system running smoothly. Diamond Club members get discounted pricing on all services. Enjoy peace of mind knowing you’ll receive a free seasonal system inspection, priority scheduling, and no after-hours or holiday fees.
Call Frank’s Repair Plumbing for AC Repair and Maintenance in Amarillo, TX
If your AC is making loud or unusual noises, it’s best to address the problem early to prevent further damage and protect your AC system. Frank’s Repair Plumbing is your go-to resource for air conditioning maintenance and repairs in the Amarillo area. Contact us to schedule a service or book online for an AC inspection or repair.
