Air conditioners (ACs) are a lifeline during hot seasons, providing comfort and relief from the heat. However, like all machines, they are prone to malfunctions. Whether your AC isn’t cooling as it should or it’s making unusual noises, learning how to troubleshoot common air conditioner issues can save you both time and money. Below is a guide to help you identify and solve the most frequent problems that plague air conditioning units. For additional tips and ideas about how to troubleshoot common air conditioner issues, be sure to visit berkeys.com/fort-worth-air-conditioning/ to learn more.

1. AC Is Not Turning On

Possible Causes:

  • Thermostat Settings: One of the most basic things to check if your air conditioner isn’t turning on is the thermostat. Ensure that the thermostat is set to “cool” mode and not “off” or “heat.”
  • Tripped Circuit Breaker: Sometimes, a tripped breaker can prevent the AC from turning on. Check the electrical panel and reset any tripped breakers.
  • Blown Fuse: The fuse in the unit’s control board could be blown. Fuses protect the unit from electrical surges but will need to be replaced if blown.

How to Fix It:

  • Check and Adjust Thermostat: Set the thermostat 5 degrees below the room temperature. If it doesn’t respond, you may need to replace the batteries or the entire thermostat.
  • Reset the Circuit Breaker: Switch off any tripped circuit breakers for the AC system, then switch them back on.
  • Inspect and Replace Fuse: If the fuse is blown, you can replace it by following the manufacturer’s instructions or consulting a professional if you’re unsure.

2. AC Is Not Cooling Properly

Possible Causes:

  • Dirty Air Filters: A clogged air filter can restrict airflow, reducing cooling efficiency.
  • Low Refrigerant Levels: Insufficient refrigerant can prevent the air conditioner from cooling properly. This might be due to a leak or insufficient initial refrigerant charge.
  • Dirty Condenser Coils: Condenser coils that are dirty or blocked by debris may hinder the cooling process.
  • Leaky Ducts: Air leaks in the ducts can result in cool air escaping before it reaches your living spaces.

How to Fix It:

  • Clean or Replace Air Filters: Air filters should be cleaned or replaced every one to three months, depending on use.
  • Check for Refrigerant Leaks: Unfortunately, refilling refrigerant is not a DIY task. If you suspect low refrigerant levels, contact a professional technician to locate and fix leaks and recharge the system.
  • Clean the Condenser Coils: You can clean the condenser unit outside using a garden hose. Make sure the unit is off and gently spray the coils to remove dirt and debris.
  • Inspect Ducts for Leaks: Look for visible gaps or damaged sections in your ductwork. Sealing ducts might involve the use of specialized tape or sealing products.

3. AC Is Leaking Water

Possible Causes:

  • Clogged Drain Line: One of the most common reasons for water leaking from an AC unit is a clogged condensate drain line. Dirt, dust, and mold can accumulate in the line and block the drainage of condensation.
  • Broken Pump: For AC systems with a condensate pump, a malfunction or break in the pump can cause water leakage.
  • Frozen Evaporator Coils: When the evaporator coils freeze, the melting ice can cause water to overflow from the drain pan.

How to Fix It:

  • Clear the Drain Line: Use a wet/dry vacuum to clear any blockages from the drain line. You may also use a stiff wire brush to dislodge debris.
  • Check the Condensate Pump: If your system uses a pump, ensure it’s working properly by testing it. If it’s broken, it may need to be repaired or replaced.
  • Thaw Frozen Coils: Turn off the AC unit and let the coils thaw. This may take a few hours. Afterward, check for airflow restrictions or refrigerant issues, which could be causing the coils to freeze.

4. AC Is Making Strange Noises

Possible Causes:

  • Loose or Broken Parts: Rattling, buzzing, or banging noises often signal loose or broken components such as screws, belts, or motor parts.
  • Debris in the Fan: If debris such as leaves or twigs gets caught in the outdoor unit’s fan, it can cause strange noises.
  • Motor Problems: A failing motor or fan may produce high-pitched squealing or grinding sounds.

How to Fix It:

  • Tighten Loose Components: Turn off the unit and inspect it for any loose screws, panels, or parts. Tighten them if necessary.
  • Remove Debris from the Fan: Shut off the power, then inspect the outdoor unit. Remove any debris caught in the fan.
  • Replace or Repair the Motor: If the motor is the source of the noise, it may need to be lubricated or replaced by a professional.

5. AC Is Cycling On and Off Frequently

Possible Causes:

  • Dirty Air Filters: Clogged air filters can cause the system to overheat, leading it to turn on and off frequently.
  • Thermostat Issues: If the thermostat is faulty or in an inappropriate location (e.g., near a heat source), it can cause rapid cycling.
  • Oversized AC Unit: An air conditioner that’s too large for your space will cool too quickly, leading to short cycling.

How to Fix It:

  • Clean or Replace Air Filters: As mentioned before, keeping air filters clean is crucial for your AC’s performance.
  • Relocate or Replace the Thermostat: Make sure the thermostat is located in an area that accurately reflects the room’s temperature, away from heat sources like direct sunlight or appliances.
  • Consult a Professional for Sizing Issues: If you suspect your AC unit is too large for your home, a professional can help you assess the situation and recommend a better fit.

6. AC Is Blowing Warm Air

Possible Causes:

  • Thermostat Settings: Your thermostat may be set to “heat” instead of “cool,” or the temperature setting might be too high.
  • Refrigerant Leak: A low refrigerant level due to a leak can result in warm air being circulated.
  • Compressor Issues: A malfunctioning compressor can’t properly pressurize the refrigerant, causing warm air to be blown instead of cool air.
  • Clogged Filters: Once again, clogged filters restrict airflow, affecting cooling performance.

How to Fix It:

  • Check Thermostat Settings: Make sure your thermostat is set to “cool” and adjust the temperature lower if necessary.
  • Call a Technician for Refrigerant Leaks: If the refrigerant is low, it will need to be recharged by a professional.
  • Inspect the Compressor: If the compressor is faulty, you will need an HVAC professional to diagnose and repair the issue.
  • Replace Air Filters: A simple filter replacement can sometimes solve the problem.

7. AC Won’t Stop Running

Possible Causes:

  • Dirty Evaporator or Condenser Coils: When coils are dirty, your AC has to work harder, causing it to run continuously.
  • Incorrect Thermostat Settings: If the temperature setting is too low or the thermostat is malfunctioning, the unit may run longer than necessary.
  • Faulty Relay Switch: A stuck relay switch can prevent the unit from turning off properly.

How to Fix It:

  • Clean the Coils: Ensure both the evaporator and condenser coils are free of debris.
  • Adjust the Thermostat: Try setting the thermostat to a more moderate temperature. If it’s unresponsive, replace or recalibrate it.
  • Call for Professional Help: If the relay switch is faulty, a professional will need to replace it.

Conclusion

Troubleshooting air conditioner issues doesn’t have to be a daunting task. By understanding some of the most common problems—ranging from improper thermostat settings and dirty filters to refrigerant leaks and motor issues—you can often diagnose and resolve issues before they escalate. However, some repairs, especially those involving refrigerants or electrical components, should be left to trained professionals. Regular maintenance, such as cleaning filters and coils, can go a long way in preventing many of these common problems, ensuring that your air conditioner keeps you cool and comfortable all season long.