Why is My Air Conditioner Making Noises?

As summer draws near, Indianapolis families are getting ready for warmer days. When you turn on the AC, you expect to feel cool, refreshing air, but what if that sensation is combined with an unusual noise? The experts at Peterman Heating, Cooling, & Plumbing can help! Here are the top 14 reasons why your AC may make noise.

1. Dirt

Your AC system has been sitting for about nine months, and Mother Nature has been busy depositing dirt in every nook, crevice, and cranny. Even if you cover the outdoor unit during the fall, dirt is a sneaky substance that can find its way inside. Try rinsing the outside unit using a spray nozzle on your garden hose. No need to remove the cover. Just direct the water into the unit as best you can. If this does not help, call Peterman Heating, Cooling, & Plumbing.

2. Belts

Your AC unit has one or more belts that can slip or tear. Damaged belts cause a high-pitched, squealing noise that may be constant or periodic. Dirt on the belt and rotating parts can also cause this noise. A technician from Peterman Heating, Cooling, & Plumbing can take a quick look, and let you know what is needed to solve the problem.

3. Coils

Coils inside your AC unit hold the refrigerant that helps cool down the air. If the connections to the coils or the coils themselves get damaged, you may hear a hissing or whistling sound. This means that the refrigerant is leaking. Finding these types of problems can be hard because refrigerant can escape from an opening as small as a pinhole. The experts at Peterman Heating, Cooling, & Plumbing know just where to look!

4. Electronics

If you hear a buzzing or clicking sound coming from the outside unit, shut down your AC system right away. This typically means that there is a problem with the electronics, and you risk damaging the AC equipment. The unit may overheat, and these types of problems can also start fires. We can schedule an emergency repair with one of our technicians.

5. Fans

Clanking, banging, and whirling are signs that the fans inside your AC unit are broken or damaged. Do not remove the cover. Fan blades can come loose, and fly through the air, causing significant damage along their path. Shut down the unit, and give us a call.

6. Bolts

Your AC system has bolts that hold the components together, as well as bolts that keep it on the concrete pad. If you notice a rattling sound, check the bolts on the outside of the unit. If any are loose, tighten them to see if that solves the problem. If the rattling continues, one of the technicians can take a look.

7. Ducts

Ducts are metal tunnels that are built into the floors, ceilings, and walls of your home. The tunnels need to be airtight to ensure that heated and cooled air is evenly distributed into the rooms. In some cases, the metal or adhesive tape that is used to connect sections of the ducts can get damaged. You may notice a thumping, whirling, or rustling noise from your AC unit. Accessing the ducts is difficult without the right tools and expertise. One of our technicians can easily locate the source of the noise and make the necessary repairs.

8. Vents

If you hear a rustling or soft banging close the vent opening of your AC system, there may be a piece of debris, such as a leaf or piece of duct tape, that is moving around. Remove the vent cover to see if you can find the culprit. If you don’t see anything, the problem may be deeper inside the ducts. A technician from Peterman Heating, Cooling, & Plumbing has special equipment to clear ducts of debris.

9. Thermostat

Do you hear clicking from your AC system? This is normal when the system turns on and off, but it should not be a constant noise. If your system quickly goes through the powering cycle, meaning that it turns on then off, and back on, there is a problem with the thermostat. You can replace the unit yourself, just make sure that you turn off the power at the circuit breaker. One of our technicians can also replace the unit. This might be a good time to upgrade to a programmable or smart thermostat.

10. Air Intake

We completely understand that the intake vent of your HVAC system is an eyesore that you would rather hide behind a sofa or other large piece of furniture, but this is not recommended. If you block the intake vent, you may hear a whirring, whistling, or rustling noise. Be sure to leave at least 18 to 24 inches of open space in front of the vent.

11. Weather

Rain, wind, and hail can make some unusual and eerie noises that seem to be coming from your AC equipment. You may hear a thumping, clanging, whistling, whirring, banging, and clicking. If you have wind or bad weather in your area, see if the noise stops as the weather clears. If it doesn’t, we are here to help!

12. Debris and Stored Items

Another problem that is caused by wind is debris and stored items banging against the outdoor unit. It may sound like a thumping from inside your home. You can check around the outdoor unit to see if you notice any objects near the unit. Debris damage can be prevented by installing an attractive fence around the unit. The experts at Peterman Heating, Cooling, & Plumbing can recommend the best materials and construction for the job.

13. Pests

No one likes pests, but little critters can make their way into your AC unit and ducts. You may hear scratching, squeaking, rustling, clicking, or short, high-pitched noises. If you suspect that pests have made a home in your ducts, or can call an exterminator to have the pests removed. We also recommend a follow-up appointment with one of our technicians to assess any damage and find where the little critters got into the ducts.

14. Normal Operation

What are some of the normal noises that you may hear from your AC unit? For the most part, modern AC units operate with little to no noise. You may notice a clicking from the system when it turns on and off, but there should be a delay between the clicks as the system cools your home. You may also hear the sound of air moving through the vents, but this should be a quiet whoosh. At the outside unit, the only noise you should hear is the fan, and it should be a low hum without any signs of vibration.

AC Experts to Stay Cool

Indianapolis families rely on the experts at Peterman Heating, Cooling, & Plumbing to keep them cool during the summer. If your AC is making noise, give us a call. We will schedule a time for one of our professional technicians to inspect the equipment and explain the necessary repairs. We also offer heating and cooling and plumbing installation, repairs, and maintenance, including 24/7 emergency repairs. We look forward to serving your home comfort needs.

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