In East Peoria, IL, high humidity and fluctuating summer temperatures are part of daily life. Your air conditioner isn’t just a convenience—it’s a necessity for staying comfortable and safe indoors. But what happens when your AC is running… and you’re still sweating?
It’s a frustrating situation many homeowners face: the unit seems to be on, but your space just isn’t cooling down. Before you panic or start pricing a new system, know this—there are several common, often fixable reasons for this issue. And many of them can be identified (and even resolved) with a bit of troubleshooting.
In this blog, we’ll walk you through the most common reasons why your air conditioner might not be delivering cool air and what you can do about it. From clogged filters to electrical glitches, we’ll cover it all—helping you make informed decisions and know when to call in the pros.
How Your AC Works: A Quick Refresher
Before we dive into the problems, it helps to understand what’s happening behind the scenes. Your air conditioning system uses a refrigeration cycle that includes four key components:
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Evaporator Coil (inside): absorbs heat from your indoor air.
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Compressor (outside): pressurizes the refrigerant and moves it through the system.
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Condenser Coil (outside): releases the heat outdoors.
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Expansion Valve: regulates refrigerant flow into the evaporator coil.
When something interrupts this cycle—airflow, refrigerant levels, electrical control, etc.—your system can’t produce cool air effectively. Let’s explore what might be causing the breakdown.
1. Check Your Thermostat First
Let’s start with the simplest possible fix.
If your thermostat settings are off, your AC may not be turning on when it should—or may be running but not cooling. Double-check these things:
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Is the thermostat set to “cool” and not “heat” or “fan”?
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Is the target temperature lower than the current room temperature?
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Is the battery in the thermostat still working (for models that use batteries)?
According to ENERGY STAR, homeowners can save up to 10% a year on cooling costs with proper thermostat settings, which also ensures the system operates as intended.
2. Dirty Air Filters Can Shut Down Cooling Efficiency
A clogged or dirty air filter can significantly restrict airflow to your system. When airflow is blocked, your evaporator coil can freeze, leading to reduced cooling performance—or no cool air at all.
Signs of a dirty filter issue include:
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Weak airflow from vents
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Unusual noises from the return vent
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Higher-than-usual utility bills
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Ice buildup on refrigerant lines or the indoor unit
According to the U.S. Department of Energy, replacing a dirty filter with a clean one can lower your air conditioner’s energy consumption by 5% to 15%.
What to do:
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Check your air filter every 30 days during heavy-use seasons.
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Replace or clean it if it looks dusty or dark.
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Always follow manufacturer recommendations for filter type and change frequency.
3. Frozen Evaporator Coils Prevent Cooling
Frozen evaporator coils are one of the most common culprits when cool air stops flowing. This can happen due to restricted airflow, low refrigerant levels, or running the system too long without a break.
Look for these signs:
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Ice or frost on the indoor coil or refrigerant lines
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Unusual hissing or bubbling sounds
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Warm air from vents even when the system is running
Troubleshooting tip:
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Turn off your AC and switch the thermostat fan setting to “on” to allow the coils to thaw.
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This can take several hours. Avoid using the system until all ice is gone.
4. Refrigerant Leaks Can Cripple Your System
Your AC system needs a specific level of refrigerant to function properly. If there’s a leak, the refrigerant pressure drops, and the system loses its ability to remove heat from your home.
Low refrigerant doesn’t just reduce performance—it can also lead to compressor damage if left unaddressed.
Common signs of low refrigerant:
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Hissing or bubbling noises
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Ice on evaporator coils
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Cooling cycles that are unusually long
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Rooms never reaching the set temperature
The EPA estimates that approximately 14% of residential AC systems leak refrigerant. And since refrigerant handling requires certification, this is one issue that always calls for professional repair.
5. Your Outdoor Unit May Be Obstructed or Dirty
The condenser coil in the outdoor unit is responsible for releasing heat pulled from inside your home. But if this unit is covered in debris—like leaves, dirt, or grass clippings—it can’t do its job.
A dirty condenser can cause:
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Warm air from vents
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Overheating or short cycling
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Compressor strain or failure
What you can do:
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Shut off the power to the system.
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Hose down the condenser fins gently from the inside out.
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Clear at least 2 feet of space around the unit.
Just be cautious—bent fins or pressure washing can damage the coil, so always clean carefully.
6. Blower Motor or Fan Problems
The blower motor is what circulates air throughout your home. If it fails, your system might still be cooling the air, but it’s not getting distributed.
Symptoms of a blower issue include:
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No airflow from vents
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A humming AC unit without interior airflow
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Sudden shutoff during operation
Blower motors can fail due to age, overheating, or lack of maintenance. While some minor issues like a tripped breaker or loose belt can be DIY-fixable, major blower issues require professional help.
7. Clogged or Leaking Ductwork
Even if your AC is producing cold air, damaged or poorly insulated ducts can prevent it from reaching your rooms. The U.S. Department of Energy reports that leaky ductwork can reduce HVAC efficiency by as much as 20% to 30%.
Warning signs include:
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Some rooms colder than others
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Increased energy bills
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Dusty or musty air from vents
East Peoria homes, especially older ones, may have aging duct systems with gaps or insulation issues. A professional inspection can help identify and repair these leaks for improved performance and air quality.
8. Electrical or Capacitor Failures
Your AC relies on several electrical components to operate, including capacitors, contactors, and circuit boards. Capacitor failure is a frequent reason for a unit that hums but won’t start.
Capacitors help start the compressor and fan motors. If one fails, your unit might:
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Struggle to turn on
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Turn on, then shut off quickly
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Run but not blow air
These are not user-serviceable parts—capacitors can hold an electrical charge even when the power is off. For safety and proper diagnosis, this issue should be handled by a licensed HVAC technician.
9. Your AC Might Be the Wrong Size for Your Home
If your air conditioner was incorrectly sized during installation, it may never properly cool your space. An oversized unit can short cycle and fail to dehumidify, while an undersized unit may run constantly without reaching the desired temperature.
Signs of poor sizing:
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High humidity indoors
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Constant on-off cycling
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Uneven room temperatures
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Long cooling times with poor results
The Manual J load calculation, used by HVAC professionals, determines proper system sizing based on your home’s size, insulation, layout, and other factors. If your system has never worked well, this might be the issue, and it requires an expert to assess.
10. Time and Wear: It May Just Be an Aging System
Even with great care, air conditioners don’t last forever. Most systems in East Peoria last 10 to 15 years, depending on use, maintenance, and build quality.
As the system ages, components wear out, refrigerant leaks become more likely, and performance decreases. You may find yourself needing frequent repairs—or living with uneven comfort levels and higher utility bills.
If your system is 12 years or older and struggling to cool your home despite clean filters and good maintenance, it may be time to consider a professional assessment and discuss whether repair or replacement is the more cost-effective solution.
For AC Repair Services in East Peoria, IL, Contact Lambie Heating & Air Conditioning Today
When your air conditioner stops delivering cool air, it’s more than an inconvenience—it affects your comfort, indoor air quality, and even your energy costs. Fortunately, many common AC problems are preventable or fixable with a little troubleshooting.
But when simple fixes aren’t enough, you need a trusted HVAC partner. That’s where Lambie Heating & Air Conditioning comes in. Our team has years of experience diagnosing and repairing AC issues for homeowners throughout East Peoria, IL. Whether it’s a refrigerant leak, blower motor failure, or ductwork problem, we’ll pinpoint the issue and get your home back to the cool, comfortable place it should be.
Our technicians are trained, certified, and dedicated to providing honest recommendations and dependable service. We use industry-best practices and cutting-edge diagnostics to ensure your system runs efficiently and reliably.
Don’t let the heat win—reach out to Lambie Heating & Air Conditioning for expert AC repair in East Peoria, IL. We’re here to help you stay cool, comfortable, and confident in your home comfort system.
