Noises your AC makes and what they could mean

Today’s air conditioners are quieter than ever. High-efficiency AC units incorporate sound-dampening technology and two-stage (variable speed) compressors to keep noise levels below 55 decibels. So if you hear unusual sounds coming from your air conditioner during normal operation, don't ignore them, as this could be a sign that the unit needs a repair or upgrade.

Ignoring the mysterious noises from your AC can turn minor issues into major expenses, as these noises could signal anything from needing a simple tune up to costly repairs, to replacement of the entire unit. The sooner you can determine the cause of the noise and resolve your AC issues, the better.

Here are some of the common sounds your HVAC system could make and what they may signify.


Banging is usually a sure sign that there’s a loose or broken part — a connecting rod, piston pin or crankshaft — inside the air conditioning compressor. Or perhaps, your indoor blower is unbalanced. A banging noise may also indicate that your system needs a compressor replacement


Clanking is another sign of a loose or out-of-balance part. The parts inside the sealed unit have likely failed, and the compressor itself may have become loose, possibly requiring a replacement. This sound can also mean that the indoor blower or outdoor fan and its blades are out of balance and hitting other parts. These types of issues will only get worse and create bigger problems, if ignored.


The clicking of electrical components at start-up and shutdown is a normal part of the system’s operation, but constant or ongoing clicking is not typical. It could be a sign of a defective control or a failing thermostat. There are a lot of electrical parts in your unit, so it’s critical to pay attention to potential electrical issues as soon as possible before you have bigger issues on your hand.


  • A buzzing noise from your outside unit could mean:
  • Loose parts
  • Debris in either the indoor or outdoor unit
  • Outdoor fan motor is loose or about to fail
  • Fan blades are loose or out of balance
  • The copper lines from outside to inside are rubbing against something
  • The condenser coil needs to be cleaned
  • The air filter needs to be changed
  • The blower is going bad or out of balance
  • Refrigerant leaks, resulting in your air conditioning freezing up. If it’s not cooling, this could be why.


Blower and fan noises such as squeaks, squeals and rattles may be transmitted through the duct system. Outdoor fan motors and indoor blower motors squeal loudly when they’re going bad. The blower wheel and housing will also squeal when they malfunction. For some units, this sound is normal upon start-up. You should be able to identify whether it’s a sound that the unit always makes or if it's something new.


A humming sound generally isn’t serious, but it still signals that something inside your air conditioner is off. Loose parts and refrigerant piping can cause vibration and, if left unchecked, can lead to a more serious maintenance issue. Sometimes humming or buzzing noises point to electrical problems. If the compressor hums and refuses to start, there may be an issue with the motor, though loose wiring could trigger this noise, too.


A rattling noise can mean that your air conditioner is starting to deteriorate, and some of its parts are loosening. Another cause could be twigs or leaves that have clogged your system. The electrical contractor in the equipment can also make a chattering sound, which can damage other components including the compressor if allowed to continue. Another culprit could be the fan, which rattles when loose. Your first line of defense is to check for loose screws or bolts in the unit’s casing, clean condenser coils and change your indoor air filter.


If you hear high-pitched whistling or screaming, shut the air conditioner off and call a professional right away. The most likely cause is a refrigerant leak, which not only damages your air conditioner but can also threaten your family’s health. Screaming might also indicate high internal pressure within your compressor, which is very dangerous. If your air conditioner turns off on its own, don't panic. Consider this a good thing. A sensor is doing its job to protect you from a potentially hazardous situation.

If you hear something unsettling that you believe could indicate an issue with your AC, it’s a good idea to turn off your central air conditioner unit as a precaution until it can be inspected thoroughly. Air conditioning units cost a lot to repair and replace. And while it’s never convenient to have a broken air conditioner, a yearly inspection and tune-up can prevent future problems.

AC fan not working?

Your central air conditioner has two fans: one located inside that blows cool air for your home and one located outside that blows over condenser coils in order to release heat from your home. If there are problems with either one of these fans, your home will not be able to cool properly. 

Here are some common reasons why one of your central air conditioner fans may not be working

  • Capacitor problems. A capacitor stores up energy that is used to provide power to your air conditioner’s fans. For various reasons, your capacitor can go bad and stop working properly, which will force one of your system’s fans to stop spinning. Often times a bad capacitor will need to be replaced by a professional.
  • Contactor problems. An air conditioner’s contactor is a switch in which electricity flows in and out in order to control the compressor as well as the condenser fan motor. It is common for the contactor to go bad over time, which restricts the outside fan from working properly. This is another part that can be replaced by a professional contractor.
  • Burnt out motor. Fan motors go through a lot of wear and tear, and they can burn out when they undergo too much stress. This is especially true for air conditioners that are not properly maintained. A bad fan motor is a more serious issue that will either require professional repairs or a system replacement, depending on the age and condition of your system.
  • Loose or broken belt. In older systems with belt-powered fans, the belt can get loose or break and cause the fan to stop spinning properly. This can be repaired, but it’s often a good sign that it’s time for a new air conditioner since you likely have an older and less efficient system.
  • Unit not receiving power. Some air conditioner fan problems might not be the fault of the fan’s assembly at all, but rather a power issue. Various parts of your air conditioner can overheat and trip your circuit breaker, forcing your air conditioner to shut down. If this is the case, you can flip the switch at your circuit breaker back on. However, a professional should look at repeated power issues.
  • Blocked air filter. If your air filter is severely clogged, your indoor fan might be working properly but the air that it blows will be completely blocked. If it sounds like your fan is working but you don’t feel any air in your home, check your air filter and replace it if it’s dirty.

Avoid fan issues with a tune-up

It’s important to note that many central air conditioner fan issues can be prevented by getting an annual tune-up through our maintenance program. If you would like more information on our maintenance program, give us a call at 405.243.1613.

R22: What Does This Mean For Your Old Air Conditioner?

Homeowners with older air conditioners may soon be facing a difficult choice: replace their cooling systems or continue to pursue increasingly costly and hard-to-find R22 refrigerant when their A/C unit needs a tune-up. Standards for types of refrigerants used in air conditioning system maintenance are changing, and this means that this most common and least expensive refrigerant will soon be phased out. When the phase-out is complete in 2020, R22 refrigerant will no longer be available.

R22 refrigerant, sometimes known as R22 Freon or HCFC-22 Freon, is an environmental danger because it contributes to the depletion of the ozone layer. The U.S. government has placed restrictions on R22 and has issued the requirement that R22 refrigerant must be eliminated from use in cooling systems by the year 2020. At this point, R22 will no longer be manufactured and cannot be used as a refrigerant in new air conditioning systems. R22 is being replaced by R-410A, a safer material which is the current, compliant standard refrigerant in air conditioning equipment.

The refrigerant change means several things for homeowners with older A/C units:

  1. R22 refrigerant may still be used, but it will ONLY be available through after-market sales when it is recovered from old systems that have been salvaged.
  2. Prices for R22 refrigerant have been rising and are expected to continue to rise. 
  3. The availability of R22 will be limited because it cannot be purchased new. If you need a recharge of R22 in the future, there is no guarantee that it will be available.
  4. A complete A/C system replacement may be the most cost-effective solution.

Tips to help you lower your utility bills this summer

As temperatures rise – so can the electric bill! There are some simple energy saving techniques that can help you lower electricity bills in the summertime. For best results, implement more than one method.

1. Cut down on energy leaks. This includes turning off lights and other electronics. When you leave a room, shut off the light behind you. Unplug electronics that aren’t being used, such as cell phone chargers, small appliances like toasters, or power strips that provide power for many appliances.

·  Big-screen TVs, DVD players, digital photo frames, and other appliances use more energy than you realize.

·  Unplugging an appliance is best because certain appliances use energy even if they are turned off.

·  Consult with roommates or coworkers before unplugging a shared appliance.

2. Spend time outdoors. Spending a lot of time indoors will naturally lead to higher energy costs because you will be using lights, electronics, and air conditioning. Spending more time outdoors means you can turn off indoor electronics, and in the process, you will have fun going to the lake, the park, the movies, and so on. Turn off all electronics before leaving the house.

3. Close blinds, storm windows, or shades during the day. The sun can heat up a room very quickly. Keeping the sun from shining into windows will cut down on cooling costs, and many stores sell curtains specifically designed for this purpose.

4. Use fans instead of air conditioning. Circulation is important to using less air conditioning during the summer. Cool down the house early in the morning by placing a box fan in the window and opening up another window at the opposite end of the house, in addition to turning on ceiling fans. Box fans sit perfectly in most windows and help cool air come inside.

·  Most central air conditioners will also have internal fans to help circulate the air in your house while reducing your need to use the air conditioner. Turn the fan on “auto.”

·   Using fans at night will help a natural breeze cool down your house; this will only work if you live in an area that drops in temperature at night.

·   Turn a fan directly towards yourself or guests if the temperature is very hot.

5. Use air conditioning efficiently. Set the thermostat to 78, and don't lower it. You can also turn the air conditioning off at night and in the early morning. If you want to invest in an energy efficient air conditioner, these are 10-15% more efficient.

·   The smaller the difference between the outdoor and indoor temperatures, the smaller your bill.

·   Do not place appliances that give off heat, such as lamps or TVs, near an air conditioner’s thermostat.

6. Use electricity during off-peak hours. If you plan to use electronics like a washer and dryer, air conditioning, and computers or televisions, try to do so during off-peak hours like early in the morning or late at night. Electrical companies charge less for energy consumed during off-peak hours.

·   It is recommended you wait until after 6 pm to cook, do laundry, or wash dishes on days the temperature is over 90 degrees.

·   Contact your local electrical company for more information on local peak hours.

7. Use energy efficient appliances. Microwaves, pressure cookers, or outdoor grills use less electricity than stoves and ovens. You can also use a clothesline instead of a dryer. When purchasing new products, look for energy efficient options.

8. Plant shady trees on the west and south sides of your house. This is a more permanent solution to cutting down summer energy costs, and it is only possible if you are a homeowner or if you get permission from your landlord. The shady trees will cut down on cooling costs for your home.