What causes common AC issues?

If you are a homeowner or renter, you will likely experience an issue with your air conditioner at some point. It’s almost inevitable. With summer just around the corner, you will want to check your system before a significant maintenance mishap occurs. To help you identify the issue and prevent a high energy bill, we recommend familiarizing yourself with the most common AC problems and solutions by reading up on them.

It’s essential to get familiar with various common air conditioning issues so that you may take necessary precautions and avoid expensive repairs. It’s important to plan routine maintenance and tune-ups with qualified Chas Roberts experts to get the finest AC performance and avoid expensive air conditioner repairs.

In this blog, you will learn about the most common types of AC issues, so you know what to expect if a future problem arises with your system.

AC that never stops running

During hotter temperatures, it is normal for your air conditioner to function more often. However, it should still be turning off and on intermittently, not continuously running without any breaks.

An air conditioning system that constantly runs may indicate an issue with the thermostat, compressor, air filters, or electrical components. We recommend to first check your air filters to see if they need to be replaced. If the thermostat or an electrical problem is the issue, it may have something to do with the relay switches. To solve this issue, you typically need to replace your thermostat.

Strange noises

The last thing you want to hear from your AC unit are strange noises. A worn-out or improperly positioned belt is the most common cause of squealing noises. Grinding noises frequently indicate strange noises that a motor-bearing problem could also be the cause. A rattling sound may result from a problem with the fans, motor, or compressors. Call a technician immediately if you are experiencing strange noises from your system.

Blowing hot air

When it’s the middle of a hot Arizona summer, the last thing you want to experience is a system blowing hot air.

Hot air could be a sign of a clogged air filter, a ductwork blockage, or dust overheating the compressor. To avoid clogs, change the air filters every few months and schedule duct cleaning at least once a year. Always have a professional inspect your AC equipment for leakage so a costly repair isn’t in your future.

If the filter is not the issue, your unit may be low on refrigerant. You can check the refrigerant by feeling the two large copper lines that enter the condenser. Your levels are good if it feels cool to the touch and damp. If your lines don’t feel cool, the refrigerant levels need to be repaired by a Chas Roberts professional.

Refrigerant leak

Your air conditioner uses refrigerant to move heat from your home. You might discover you’re getting a lot of warmer air when it doesn’t have enough refrigerant.

These are a few indicators if you have a leak:

  • Insufficient cold air
  • Humid air inside the home
  • longer cooling cycles than normal
  • Condenser coils that are frozen
  • The air conditioner is making strange noises
  • Odor near the AC unit

Frozen condenser coils

An air conditioner’s coils are vital because they take heat from your home and release it outdoors.

Freezing is related to several problems, including dirty coils brought on by neglect of yearly maintenance, clogged air filters that limit airflow, a clogged drain line that may result in moisture accumulation, or leaks in the refrigeration system that reduce cooling capacity.

If you have any issues, try turning off your air conditioner and wait for the coils to thaw. Turn on the AC fan to see if this resolves the problem. This may take some time, so let the fan run for at least 24 hours. You may need to call an expert if the problem continues.

Unclean air filter

To avoid issues like reduced airflow and poor air quality, replace your AC filters every few months.

Remember, regular HVAC maintenance is necessary for optimal performance. Yearly maintenance is essential for your air conditioning system, whether you have experienced any issues or changes in performance. Proper system service should prevent you from ever having a problem.

Thermostat Issue

Your air conditioner can malfunction or regularly cycle on and off if your thermostat isn’t operating correctly. When the thermostat is adjusted to the lowest setting and the air conditioner still won’t turn on, it’s time to call a professional at Chas Roberts. When this happens, your thermostat may be old and not properly functioning as you want it to. Therefore, it will have to be replaced.

Condenser issue

If the condenser is broken, the AC will blow warm or no air at all. Broken tubes and leaks inside the seals bring on condenser issues. These tubes may crack after prolonged usage, but a qualified technician can fix them and keep your AC running. Another reason for a problem with the condenser can also be the result of debris and dirt buildup.


It’s important to know the signs of when you AC unit is experiencing issues. To ensure that your system continues to perform at its very best for an extended period, it is crucial to schedule routine air conditioning maintenance. HVAC units need regular maintenance to ensure they run correctly and efficiently.

A maintenance visit from Chas Roberts includes a 26-point maintenance check, which separates us from other air conditioning and heating companies across the valley. Chas Roberts services 28 cities in Metro Phoenix and Tucson and provides exceptional, one-on-one customer service and knowledgeable advice on your air conditioning maintenance.

Chas Roberts is the oldest and largest family-owned residential HVAC company in Arizona and has been in business for over 75 years. Contact us for quality, reliable service.