AC PROBLEM · DIAGNOSIS GUIDE

AC Making Loud Noises — What Does Each Sound Mean?

Strange AC noises are often the first warning of a coming failure. Catching the issue early usually means a cheaper repair.

Since 1999NJ Lic #19HC0010870024/7 DispatchSame-DayNewton, NJ
Why It's Happening

Decoding the Sound

1

Banging or clanking

Usually a loose or broken part inside the compressor — fan blade, piston, connecting rod. Stop running the system and call us.

2

Buzzing

Often an electrical issue — failing contactor, capacitor, or relay. Sometimes vibration from a loose mounting.

3

Grinding

Motor bearings are failing. Catch this within a few days and you can replace the motor for $400-$700. Wait until the motor seizes and you may need a new system.

4

Hissing

Refrigerant leak in most cases. Sometimes a valve issue. Either way, professional diagnosis is needed.

5

Squealing

Often a worn fan belt (on older systems) or a failing blower motor. Quick fix if caught early.

6

Clicking that won't stop

Failing thermostat, control board, or relay. The system is trying to start but failing.

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What to Do

Most noisy-AC repairs catch the failure before it becomes a full breakdown. Cost is significantly lower if you call when you first hear the sound versus after the system fails completely.

Same-day appointments available in Newton and Sussex County. Call (973) 948-0680. Diagnostic fee waived when you book the repair.

27 yrs
Since 1999 in Sussex County
24/7
Real techs answer — not voicemail
NJ Lic
HVACR #19HC00108700
$0
Diagnostic fee waived when you book repair
★★★★★

The grinding noise turned out to be a failing blower motor. They explained the choice — replace now for $500 or wait until it dies and replace it under an emergency call for more. Easy call.”

Mark T. · Randolph, NJ

Talk to a Tech Now

A licensed technician picks up. Not a call center.

Same-day appointments in Sussex and Morris counties. 24/7 emergency dispatch — answered around the clock by a real on-call technician.

98 Morris Turnpike, Newton NJ · NJ HVACR Lic #19HC00108700 · Since 1999

At Constant Air, we specialize in delivering high-quality heating, ventilation, and air conditioning services that keep your home and business comfortable all year round.

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