WEIRD NOISES COMING FROM MY AC: WHAT COULD BE WRONG?

Admin • August 17, 2022
Air Conditioning Fan — Colorado Springs, CO — Home Heating Service, Inc.

Even a perfectly functioning AC unit will make some noise. For example, you might hear a faint humming sound when it kicks on. The humming noise is perfectly normal and nothing to worry about, but if your AC unit starts making strange, unfamiliar noises, that’s a different story.

TYPES OF AC SOUNDS AND THEIR SIGNIFICANCE

All sorts of strange noises can come from your AC unit, and they usually indicate a problem. The first step is to identify the type of noise you’re hearing. Let’s consider some of the common sounds your AC might produce and what they mean.


HUMMING NOISE

If you hear humming sounds from your AC unit, it’s likely coming from the compressor. The compressor is a motor that circulates the refrigerant through the AC. If the noise is constant and not too loud, it’s probably nothing to worry about, but if the humming noise is accompanied by other strange noises or gets louder over time, it could signal that the compressor is going bad and will need replacement.


HISSING OR SIZZLING NOISE

If you hear hissing or sizzling noises, it’s probably because there’s a refrigerant leak in the AC unit. Refrigerant is what helps cool the air, so if there’s a leak, the AC won’t be able to function properly. Leaking refrigerant could harm your AC unit and your health, so fixing it as soon as possible is important. When you hear this sound, switch off the AC and call a professional for help.


RATTLING SOUND

Many components make up your air conditioning system, and they’re all held together with screws, nuts, and bolts. If you hear a rattling sound, it’s likely because one of these components has come loose. It is usually an easy fix — simply tighten the component. However, it’s best to call a professional if you can’t identify the noise source or if the rattling persists after you’ve tightened everything up.


The rattling noise could also result from debris caught in the AC. Cleaning and servicing your AC can help prevent this from happening.


SQUEALING OR SCREAMING SOUND

If your AC starts making a high-pitched squealing noise, it’s likely because the bearings in the fan motor are going bad. The bearings help the fan rotate smoothly, and when they start to fail, they can produce a loud squealing noise. Replacing the bearings is a fairly simple repair that can be done by a professional.


This noise could also be due to worn-out belts. The AC unit has a series of belts that help move different parts of the system. If these belts wear out, they can start slipping and making a squealing noise. Replacing the belts is usually a quick and easy fix.


CRANKING SOUND

If you hear a cranking sound coming from your AC unit, it’s likely because the starter capacitor is going bad. The starter capacitor helps the compressor motor start up, and when it starts to fail, it can produce a cranking noise. Replacing the starter capacitor is a fairly simple repair that can be done by a professional.


This noise could also result from a problem with the compressor motor itself. If the motor is failing, it can produce a cranking noise when you try to turn on the AC unit. Replacing the compressor motor is a more complex repair that should be done by a professional.


BUZZING NOISE

A problem with the electrical components usually causes a loud buzzing noise from your AC. This could be something as simple as a loose wire or a blown a fuse. The noise could also result from contactor failure. The contactor is an electrical switch that turns the compressor on and off. If it’s failing, it can produce a buzzing noise.


It can be hard to diagnose the source of most of these sounds. That’s why you need the input of our experts at Home Heating Service, Inc. to help you figure out what’s going on with your noisy AC unit.


WHY YOU SHOULDN’T IGNORE STRANGE NOISES COMING FROM YOUR AC

When an AC makes a strange sound, it’s usually a sign that something is wrong, and if you ignore these sounds, it could lead to more serious problems like a complete system failure. Also, if there’s a case of leaking refrigerant, it could harm your health.


WE ARE HERE TO HELP!

At Home Heating Service, Inc., we take pride in being a premier AC repair, maintenance, and installation service provider in Colorado Springs. Besides AC services, we specialize in heating installation, maintenance, and repair, home energy audits, green comfort, and water quality.


Contact us today to schedule an appointment with one of our experts.

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