Why is My AC Blowing Warm Air? Common Issues and Fixes
By Zachary Morgan | The Repair Blog | AC Service in Ruston, Louisiana & Surrounding Areas
There’s nothing worse than coming home on a hot Louisiana day, cranking up the air conditioner — and realizing it’s blowing warm air.
If your AC is acting more like a heater, don’t panic. At Alltec, we’ve helped hundreds of homeowners in Ruston and surrounding areas troubleshoot and repair AC systems, and we know the common culprits behind this frustrating problem.
In this post, we’ll break down the most common reasons why your AC might be blowing warm air and what you can do about it.
🔧 1. Incorrect Thermostat Settings
It might sound simple, but check your thermostat first. Sometimes it’s accidentally set to “heat” or “fan only.”
Fix:
Make sure it’s set to “cool” and the temperature is set lower than the current room temp. If you have a smart thermostat, check the app or settings screen for any unusual programming.
🧊 2. Low or Leaking Refrigerant
Refrigerant is what cools the air inside your AC system. If your system is low on refrigerant (usually due to a leak), the air won’t be cooled properly — and you’ll feel warm air from the vents.
Warning Signs:
Hissing or bubbling sounds
Ice forming on refrigerant lines
AC running constantly but not cooling
Fix:
This isn’t a DIY job. You’ll need a certified HVAC technician to:
Locate and repair the leak
Recharge the refrigerant to manufacturer levels
Test for pressure and cooling efficiency
Alltec offers quick response AC leak repair and recharging throughout Ruston and surrounding areas.
🌬️ 3. Dirty Air Filters
A clogged air filter restricts airflow, causing the system to work harder and cool less effectively. In extreme cases, it can even cause the system to overheat and shut down.
Fix:
Check your air filter. If it’s dirty or hasn’t been changed in over a month, replace it. For homes in dusty or high-pollen areas like northeast Louisiana, filters may need to be replaced more frequently.
⚙️ 4. Electrical or Breaker Issues
Your outdoor AC unit (the condenser) needs power to cool the air. If it’s not getting power — even if your indoor fan is running — the system will blow warm air.
Fix:
Check your breaker box for a tripped breaker
Reset if necessary
If it trips again, call a professional — there could be an electrical fault
🧼 5. Dirty or Blocked Condenser Unit
The condenser unit (usually located outside) releases heat from your home. If it’s covered in dirt, leaves, or grass clippings, it can’t expel heat properly — and your AC starts blowing warm air.
Fix:
Turn off the power to your unit
Carefully remove debris and clean the fins using a garden hose (not pressure-washing)
For deep cleaning, call a technician
💻 6. Faulty or Aging AC Components
Over time, AC components like capacitors, compressors, or the expansion valve can fail or wear out, leading to cooling issues.
Fix:
Professional diagnostics are required to test these components. If your unit is 10–15+ years old, it may be more cost-effective to consider a replacement.
🛠️ 7. Ductwork Problems
If your ductwork is leaking or poorly insulated, cool air could be escaping before it reaches your vents. This is especially common in older homes or during renovations.
Fix:
Schedule a ductwork inspection to locate leaks, gaps, or insulation issues. Alltec offers duct repair and sealing services for homeowners in Ruston, Monroe, and beyond.
🧯 Bonus Tip: Check for Emergency Shutoff Switches
Some AC systems have a shutoff switch or float switch that trips when water accumulates in the drain pan. This safety feature disables the cooling function to prevent water damage — but your fan may still run, giving the illusion that it’s "blowing warm."
✅ When to Call an HVAC Professional
If you’ve tried the basic troubleshooting steps and your AC is still blowing warm air, it’s time to call the pros.
At Alltec, we provide fast, honest, and affordable AC repair services for homeowners in Ruston, LA and nearby communities. Whether it’s a simple fix or a more serious system issue, we’ll get your home cool again — guaranteed.
📞 Ready to Fix Your AC? Contact Alltec Today!
Local Experts in Ruston, Monroe, West Monroe, and Farmerville
Licensed & Insured HVAC Technicians
Same-Day Appointments Available
Transparent Pricing – No Surprises
👉 Call us or book your appointment online now! @ (318) 255-9020