As temperatures rise, air conditioner problems can quickly escalate. Whether your system is blowing warm air or won’t turn on at all, a malfunctioning AC can turn your home into a sauna.
The good news? Most common AC problems can be identified and resolved before they turn into bigger (and more expensive) issues. In this series, we’ll walk through the most frequent air conditioner issues, explore what typically causes them, and offer solutions ranging from simple DIY fixes to calling in the pros.
MRCOOL® has your back if you’re feeling overwhelmed, too. With innovative, energy-efficient, and easy-to-install HVAC equipment ranging from mini splits to central systems, you can stay cool all season long. Plus, our great support team handles air conditioner problems and solutions all day long. They're just a click away.
Before you call for backup, try these three quick fixes.
1. Not Cooling Properly
This is the most frequent of all AC complaints. When your unit is running but not cooling your home effectively, it’s easy to get frustrated.
Check for these culprits:
Dirty air filters
When filters are clogged with dirt and debris, airflow is restricted and the system struggles to push cool air through the ducts.
Obstructed vents
Blocked or closed vents restrict airflow, forcing your HVAC system to work harder, spike your energy bills, and create uneven temperatures. Walk your home and ensure every vent is fully open, blowing air, and completely clear of furniture or decor.
Homeowner tip: Set a calendar reminder to change your filters monthly during heavy use seasons like summer. A mini split system will require more frequent filter cleanings than a central system, so be sure to check them more often. Also, ensure your outdoor condenser unit is free of obstructions like grass, mulch, or leaves.
2. Won’t Turn On
If your air conditioner refused to turn on, don't panic. Start with the basics:
- Thermostat settings
- Ensure it’s set to “cool” and the temperature is lower than the current room temperature. Yes, this seems obvious, but you would be shocked at the number of service calls that lead back to this being the problem.
- Use a thermostat with an easy-to-read digital display like the MRCOOL® Smart Wi-Fi Thermostat to ensure your settings are always spot-on.
- Circuit breaker
- Still nothing? Head to your electrical panel and look for a tripped circuit breaker. It’s a small fix, but one that’s easily overlooked. Dead thermostat batteries could also be the culprit. Additionally, check any shut-off switches near the unit itself. One may have been flipped for cleaning or maintenance and never reset.
- Power switches
- If you’ve gone through these steps and your system still won’t power on, it's likely a wiring issue, a blown capacitor, or another technical problem. Difficulties like these should only be handled by a certified HVAC technician. Continuing to troubleshoot electrical issues without proper training can be dangerous and will almost certainly void your warranty.
3. Weak Airflow From Vents
Poor airflow is another common air conditioning issue and can lead to uneven cooling, higher energy bills, and greater strain on your system.
Possible reasons include:
Clogged filters or a malfunctioning blower motor
Leaky or obstructed ductwork
Degraded duct insulation
What to do: Swap out dirty filters for new ones. Make sure no furniture or rugs are blocking return air vents. You can also try removing vent covers and vacuuming out visible dust. If airflow remains weak, the blower motor, duct system, or even your system’s overall design may require professional evaluation.
But if your air conditioner keeps breaking down every summer, it might be time to compare the cost of another repair against the benefits of a total replacement. At MRCOOL®, we design reliable, highly efficient HVAC systems that work smarter to keep your indoor air clean, fresh, and comfortable all year long. Ready to make the switch to a more effective cooling solution? Locate a dealer near you or visit mrcool.com to learn more.