What Are the Most Common AC Problems?

AC units are machines that need to be regularly maintained and cared for. When an AC unit isn’t regularly maintained, inspected, tuned up, or serviced, it will develop problems affecting efficiency and even reducing lifespan.

Air conditioning service technicians recommend scheduling a professional maintenance check-up twice a year to keep your AC in peak working conditions and avoid costly repairs. Some of the most common AC problems that homeowners will run into if they don’t take care of their AC units and other factors include:

Refrigerant Leaks

A refrigerant leak prevents your AC from cooling your home efficiently and poses health risks, especially if mold develops in your home. Suppose you don’t fix a refrigerant leak promptly. In that case, it can affect your AC compressor or other crucial components, resulting in system failure and significantly costlier repairs or total replacement. Some of the signs that you should notice if you are dealing with a refrigerant leak include:

  • Hissing sounds
  • Excessive moisture or water leakage around the unit
  • Oily residue
  • Automatic system shutdown

Usually, the most common reasons why refrigerant leaks occur are attributed to wear and tear, factory defects, corrosion/erosion, or poor installation, among other things. DIY solutions cannot mitigate this AC issue. Contact an HVAC professional right away if you experience refrigerant leaks.

Frozen Evaporator Coil

Your AC indoor unit contains evaporator coils that can freeze and restrict airflow, negatively impacting the unit’s cooling efficiency. Evaporator coil issues can be prevented in most cases through regular maintenance as sometimes dirty air filters or low refrigerant levels can cause the coils to freeze. However, problems with your AC motor blower or thermostat can also lead to frozen evaporator coils.

Dirty Condenser Coils

The outdoor AC unit contains the condenser coils. Over time, these coils can get dirty and hindered due to the accumulation of dust, dirt, and other debris. Dirty coils cannot perform efficient heat transfer operations. This can affect cooling efficiency and result in higher energy consumption rates, as well as further damage to components. As a homeowner, you can mostly prevent this by checking the outdoor unit monthly and clearing it from debris.

Faulty Capacitors

The motors in your AC unit start to work with the help of electrical components such as capacitors. When these capacitors fail, your AC motors will struggle or won’t be able to start functioning. Your AC might not turn on because of this, or you may hear unusual clicking or humming sounds coming out of it.

Malfunctioning Fan

Sometimes, your outdoor unit’s fan motor or blades can become damaged or malfunction due to various reasons, such as wear and tear or improper installation. If your fan malfunctions, your unit will be hindered in expelling heat, which will affect cooling performance and cause other issues. Contact an HVAC service provider to have your unit inspected and the damage assessed.

Any unfamiliar sounds coming from your AC often indicate major issues that only an expert can handle properly. If the sounds are accompanied by a foul odor, request an inspection right away.

Clogged Air Filters

Air filters usually need to be changed once every three months or so, depending on what type of air filters you use, usage, the presence of pets, and other external factors and manufacturer recommendations.

If you do not change your air filters regularly, they can easily become clogged and restrict airflow. When your AC suffers from restricted airflow, your system will experience increased strain. The cooling efficiency will decrease, and in time, the evaporator coil can also freeze. To ensure the longevity of your AC, proper functioning, and efficient energy usage, replace your air filters regularly.

Thermostat Issues

Thermostat issues are a common AC problem. Sometimes, a simple thing, such as the depletion of your thermostat’s batteries, can cause it to cease operating. If you don’t have a thermostat operating on batteries and you experience issues with it, then other more severe issues may be at hand.

Thermostats are crucial components that can damage your AC system if they don’t work properly. If the thermostat cannot accurately perform temperature readings, you must service it immediately. It might be a sensor issue. Inadequate cooling or uneven temperature control can result from a faulty thermostat.

Electrical Problems

All AC units rely on various electrical connections for proper operation, and electrical problems are a common issue that most homeowners will deal with more than once due to various reasons, such as faulty wiring, tripped breakers, or blown fuses.

These types of electrical problems must be dealt with by a licensed professional as they pose a significant danger. Do not attempt to resolve these issues if you do not have the necessary expertise. Turn off your AC to prevent further damage to your system, and contact a professional.


AC units have a condensate drain line that removes moisture generated during the cooling process, but these drain lines can sometimes become clogged or blocked. When this occurs, you should expect water leakage or a complete system shutdown. This happens as a protective measure to prevent further damage to your unit.

Compressor Issues

Your AC compressor is among its most crucial components responsible for circulating the refrigerant and helping cool the air. Sometimes, these components can become faulty due to wear and tear, motor failures, or refrigerant flow problems. Compressor issues will result in inadequate cooling or complete system failure and is not an issue that you should attempt to handle by yourself.

Contact a licensed HVAC technician who can diagnose the issue accurately, perform the necessary repairs or maintenance, and restore your AC unit. AC problems become more common as your unit ages and if regular maintenance isn’t performed.

In some situations, common issues can lead to premature AC unit replacements, so you should always prioritize maintenance and inspection schedules if something is wrong. Let your local HVAC technician deal with the complex aspects of your AC unit. If you want to address certain issues, be aware that you can void your warranty. Focus only on simple maintenance tasks such as changing air filters or cleaning, and call an expert when you require assistance.

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button