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AC Making Strange Noises
in Arlington, TX
Your AC should hum quietly. When it starts banging, rattling, squealing, or clicking, something inside has worn out or come loose. Arlington units run long hours from late spring all the way into fall, which puts a lot of wear on moving parts. Some noises are minor. Others mean the unit is a few days away from breaking down completely.
Quick Answer
Strange noises from your AC usually mean something is loose, worn out, or about to fail. Banging or clanking often means a broken part inside the unit. Squealing usually means a belt or bearing is going bad. In Arlington, where units run hard from May through October, worn parts are common. Call (817) 670-3733 and describe the sound — that helps narrow it down before anyone comes out.
Telltale Signs
Warning Signs to Watch For
- A loud banging or clanking sound when the unit starts or runs
- A high-pitched squealing or screeching noise from the outdoor unit
- A rattling sound coming from the vents or the air handler
- Clicking sounds that don't stop after the unit starts
- A bubbling or hissing noise near the refrigerant lines
Root Causes
What Causes AC Making Strange Noises?
Loose or Broken Fan Blade
The fan in the outdoor condenser unit can get hit by debris or simply loosen over time. When a blade is bent or loose, it wobbles and hits the inside of the unit, making a banging or clanking sound. During spring in Arlington, hail and windblown sticks can damage fan blades on units that sit in open backyards.
The Fix
Fan Blade Replacement
A technician removes the damaged blade and replaces it with the correct size. Running the unit with a bent blade can damage the fan motor, so this should be handled quickly.
Worn Blower Motor Bearings
The blower motor inside your home moves air across the coil and through the ducts. The bearings inside it wear down over time, and when they go, the motor makes a squealing or grinding sound. Units in homes built in the 1980s in neighborhoods like Johnson Creek often have original blower motors that are well past their expected life.
The Fix
Blower Motor or Bearing Replacement
A technician checks whether the bearings alone can be serviced or whether the full motor needs to be replaced. A motor that's grinding usually needs to be replaced before it seizes up completely.
Refrigerant Leak Making Hissing Sound
A hissing or bubbling sound near the refrigerant lines usually means gas is escaping through a crack or a loose fitting. This can happen at the coil connections or along the copper lines that run between the indoor and outdoor units. The longer it goes, the more refrigerant is lost.
The Fix
Leak Detection and Line Repair
A technician uses a leak detector to find exactly where the gas is escaping, seals or replaces that section, and then recharges the system. Ignoring this sound will lead to a full freeze-up or a unit that won't cool at all.
Self-Diagnosis
Which Cause Applies to You?
Check the signs you're observing to narrow down the likely root cause before your inspection.
| What You're Seeing | Loose or Broken Fan Blade | Worn Blower Motor Bearings | Refrigerant Leak Making Hissing Sound |
|---|---|---|---|
| Loud banging sound that starts when the outdoor fan turns on | |||
| Squealing or grinding from inside the house near the air handler | |||
| Hissing sound near the copper lines outside | |||
| Noise stops when you turn the fan setting to off | |||
| Sound started right after a spring hailstorm |
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