The last thing you need on a hot, humid Wilmington summer day is an air conditioner that’s running but not cooling. If you find your AC is on yet the air coming from the vents isn’t cold, don’t panic – this is a common problem with a number of potential causes. Some fixes are simple enough to do yourself, while others require professional repair. Below we’ll go through some of the most common reasons an air conditioner isn’t blowing cold air and what you should do in each case.
1. Thermostat or Power Issues
Before jumping to worst-case scenarios, check the basics. An AC that isn’t blowing cold air may simply not be told to cool, or it might not have power. First, check your thermostat: ensure it’s set to “Cool” (not just “Fan”) and the temperature is set lower than the current room temp. Next, check the power to your system. Summer power surges or lightning storms in Wilmington can trip the AC’s circuit breaker, so see if the breaker has tripped and reset it if needed. Also replace the thermostat batteries if needed.
If correcting these settings or restoring power fixes the issue, your AC should kick back on and start blowing cold air in a few minutes. However, if the breaker immediately trips again or the AC still won’t run, there may be a deeper electrical problem – it’s time to call a professional HVAC technician.
2. Clogged Air Filter Restricting Airflow
One of the most common reasons for an AC to lose its cooling is a dirty air filter. If the filter is clogged with dust and debris, it stifles airflow through the system. With insufficient warm air passing over the AC’s indoor evaporator coil, that coil can get too cold and actually freeze up into a block of ice. When the coil is frozen or airflow is severely reduced, you’ll feel little to no cool air from your vents.
Turn off your AC and inspect the filter. If it looks dirty or gray, put in a fresh filter. In our Wilmington climate, it’s smart to check your AC filter every month in summer, as heavy use can clog it quickly. If your evaporator coil did ice up, leave the AC off for a few hours to let the ice melt before restarting. Once airflow is restored with a clean filter (and the coil has thawed), your AC should be able to blow cold air again. You’ll likely notice a stronger, cooler airflow after this simple fix.
3. Low Refrigerant (Cooling Leak)
Your air conditioner relies on refrigerant to absorb heat and cool your home. If the system becomes low on refrigerant, it won’t cool effectively. Low refrigerant almost always means there’s a leak – refrigerant doesn’t get “used up” like fuel. Signs of this issue include the AC running continuously without reaching the set temperature, air from the vents only mildly cool, or even ice forming on the indoor or outdoor coils. You might also hear a faint hissing or bubbling sound, indicating refrigerant escaping.
Unfortunately, there’s no DIY remedy for a refrigerant leak. You’ll need a licensed HVAC technician to locate and fix the leak, then recharge the system with the proper refrigerant. After a professional repair and recharge, your AC should blow cold air normally again.
4. Outdoor Unit Problems
Your air conditioner’s cooling ability also depends on the outdoor condenser unit. If the outside unit isn’t running properly, you’ll end up with warm air inside. If the condenser coils (the metal fins on the outdoor unit) are clogged with dirt or yard debris, the AC can’t release heat efficiently, and your indoor air won’t get very cold. Or, if the outdoor unit’s fan isn’t spinning or the compressor isn’t kicking on, the AC can’t cool at all.
Turn off the power and gently rinse the outside coils with a garden hose to wash away dirt and debris (make sure the unit’s power is off before cleaning). Clearing the coils can improve cooling performance. If the outdoor fan or compressor isn’t running at all (and you’ve checked the breaker as in step 1), it’s time to call a professional. An HVAC technician can repair or replace the failed parts to get your outdoor unit running and your home cool again.
Wrapping Up
Don’t suffer in the Wilmington heat with an AC that won’t cool. If your AC still isn’t blowing cold air after basic troubleshooting, call in the experts. The certified technicians at Air Support Heating & Cooling can quickly diagnose the issue and get your system back to blowing cold air. We provide prompt, professional AC repair throughout Wilmington, NC, and surrounding areas. Contact Air Support Heating & Cooling today to restore comfort in your home and stay cool all summer long!