Your AC is running but blowing warm air. Here are the 5 most common causes in Joliet, IL.
1. Low Refrigerant (Refrigerant Leak)
Refrigerant absorbs heat from your home. If low, the AC cannot cool properly. Low refrigerant always means a leak — simply recharging without fixing the leak is a temporary fix. A licensed technician finds the leak, repairs it, and recharges to the correct level.
2. Failed Capacitor
The capacitor starts the motors in your AC. When it fails, the outdoor unit hums but will not start, or trips the circuit breaker. Cost: $150–$300, usually under 30 minutes to replace.
3. Dirty or Frozen Evaporator Coil
A dirty or frozen indoor coil cannot absorb heat. Signs: ice on refrigerant lines, water pooling, reduced airflow from all vents. Check your air filter first — a clogged filter is the number one cause of frozen coils.
4. Clogged Condenser Coil (Outdoor Unit)
The outdoor unit releases heat outside. If blocked by dirt, grass clippings, or cottonwood seeds (common in Illinois), cooling capacity drops significantly. You can gently rinse it with a garden hose.
5. Thermostat Problem
Check these first: fan on AUTO (not ON), mode set to COOL, temperature set lower than current room temp, batteries fresh. These simple issues cause many service calls.
What To Do
- Check thermostat settings
- Check and replace air filter
- Check circuit breaker for outdoor unit
- Check outdoor unit is running and unblocked
- Call (815) 212-7662
Need AC Repair in Joliet, IL?
Same-day service available. All major brands. Bilingual EN/ES.
Call (815) 212-7662AC Repair PageFrequently Asked Questions
My AC runs but will not cool below 80 degrees. What is wrong?
Most likely causes: low refrigerant, dirty condenser coil, undersized system, or failed compressor. Call (815) 212-7662 for a diagnosis.
Can I fix low refrigerant myself?
No. EPA Section 608 certification required. A licensed technician must find the leak, repair it, and recharge the system correctly.
How much does AC repair cost in Joliet, IL?
Capacitor: $150-$300. Refrigerant recharge with leak repair: $300-$600. Coil cleaning: $150-$300. Compressor: $800-$2,000+. We diagnose first. Call (815) 212-7662.
Is it safe to keep running my AC if it is not cooling?
Turn it off. Running with low refrigerant damages the compressor. A frozen coil needs to thaw before restarting. Call (815) 212-7662.
About Heavy Duty Heating & Cooling: Family-owned HVAC in Joliet, IL. Licensed & insured. Bilingual EN/ES. 24/7. Call (815) 212-7662.