5 Reasons Why your Air Conditioner is Not Cooling Properly?


Are you frustrated with your air conditioner running but not cooling properly? Don’t sweat it! A malfunctioning AC can make hot summer days unbearable and lead to increased energy bills. You deserve to stay cool and comfortable without worrying about your utility costs skyrocketing. That’s why we’ve created this quick-fix guide to help you diagnose and solve common air conditioning cooling issues quickly.

We’ll cover problems like thermostat issues, frozen evaporator coils, clogged air filters, and low refrigerant levels—all of which can significantly impact your AC’s cooling efficiency. We’ll also offer practical solutions to restore your AC’s performance. Whether it’s cleaning the outdoor unit or ensuring your thermostat is properly calibrated, you’ll find simple yet effective fixes that will have your AC running smoothly again.

Still facing cooling issues after following this guide? Contact All Pro Heating, Air & Plumbing for expert AC repair and maintenance in Indianapolis. Our team will quickly identify the root cause and restore your cooling comfort. Call us today and say goodbye to those sweaty summer days!

Common AC Problems & Quick Fixes

Thermostat Issues:

Is Your Thermostat Set Correctly?

If your air conditioner is running but not cooling the house properly, your thermostat could be the culprit. Ensure it’s set to ‘cool’ and lower the temperature a few degrees to kick-start the cooling process. A faulty or improperly calibrated thermostat may also cause issues, so consider replacing it if necessary. Remember to close all windows and doors and check for power supply issues to maximize efficiency.

Frozen Evaporator Coil:

Dealing with Frozen Coils

Frozen evaporator coils are commonly caused by dirty air filters, refrigerant leaks, or malfunctioning fans. When the coils freeze, they prevent proper airflow and cooling. To deal with this issue, turn off the AC and let the coils defrost completely. Replace dirty air filters and clean the evaporator coil to restore normal cooling. If refrigerant leaks or fan malfunctions are suspected, seek professional assistance to resolve the problem and prevent further coil freezing.

A man working on cleaning a mini split

Clogged Air Filter:

A Simple Fix: Cleaning or Replacing Clogged Air Filters

Clogged air filters can seriously mess with your AC’s cooling power by reducing airflow. The good news? Fixing this problem is easy! Just check your air filters every 1-3 months and clean or replace them if they look dirty.

Make sure you’re replacing your filters that fit your specific AC model. Keeping those filters clean will ensure proper airflow, ease the strain on your system, and keep your home nice and cool. Regular filter maintenance is a simple trick that can save you from bigger AC headaches later on!

For more DIY tips on cleaning your dirty AC air filter and keeping your AC cooling efficiently, check out our previous blog.

Tripped Breaker or Blown Fuse:

“Is Your Circuit Breaker Causing Cooling Issues?”

A tripped circuit breaker can cut power to your AC unit, leaving you sweating it out in the heat. Here’s a quick fix: head to your circuit breaker panel and reset the breaker or replace the fuse if needed.

If your AC still won’t turn on, it might be time to call in a technician to investigate further. Don’t worry; it’s a common issue, and getting a pro to take a look will have your AC back up and running in no time!

Low Refrigerant Levels:

Is Your AC Low on Refrigerant?

If you’re noticing ice buildup, hissing sounds, or warm air coming from your AC, it could be low on refrigerant. Since only certified technicians should handle refrigerant leaks, it’s best to call in a pro for this one. If you notice ice, immediately turn your cooling system off, but leave the fan running.

To avoid surprises, schedule annual AC maintenance and have your refrigerant levels checked regularly with professional help. Stay ahead of the game and keep your AC running smoothly all summer long!

Structural & Mechanical Issues

Improperly Sized AC Unit:

Size Matters: Is Your AC the Right Fit?

An undersized or oversized air conditioner can lead to a host of cooling issues. If your unit is too small, it will struggle to cool your space efficiently, often running constantly without delivering the desired relief. Conversely, an oversized unit will cycle on and off too frequently, leaving the air feeling clammy due to poor dehumidification while wasting energy.

To ensure your AC is the right fit for your home, have a professional HVAC technician assess your cooling needs. They will consider factors like room size, insulation quality, number of windows, and sun exposure to determine the ideal unit size. Upgrading to a properly sized AC unit will not only improve cooling efficiency but also save on energy bills and enhance comfort.

Dirty Outdoor Condenser Unit:

Does Your Outdoor Unit Need a Cleaning?

Your outdoor condenser unit plays a crucial role in your air conditioning system’s cooling efficiency. Over time, dirt, debris, and vegetation can clog the condenser, reducing its ability to dissipate heat effectively. This can lead to higher energy consumption and inadequate cooling.

To keep your outdoor condenser unit functioning optimally, clean the condenser fins gently with water and soap. Be careful not to damage the fins. Additionally, ensure there’s proper clearance around the unit by trimming back any bushes, weeds, or grass that may be obstructing airflow.

dirty HVAC

Here are a few additional tips for maintaining a clean condenser unit:

  • Use a soft brush to remove surface dirt from the fins.
  • Straighten any bent fins with a fin comb.
  • Cover the unit during the offseason to prevent debris buildup.

Regular maintenance of your condenser unit will help your AC maintain optimal cooling performance, extending its lifespan and reducing energy bills.

Leaky or Poorly Installed Ductwork:

Is Your Cooled Air Escaping?

Leaky or poorly installed ductwork can significantly reduce your AC’s cooling efficiency. When ducts are not sealed properly, cool air escapes before reaching your living spaces, leading to uneven cooling and higher energy bills.

Follow these tips to keep cool Air from Escaping:

  • Use professional-grade tape (mastic or foil-backed) to seal duct leaks.
  • Insulate exposed ducts to prevent temperature loss.

If you suspect a more widespread problem, consult a technician for a thorough inspection and proper duct installation. A well-sealed and insulated duct system ensures efficient cooling and keeps your home comfortable throughout the summer.

Faulty Compressor or Fan:

Addressing Mechanical Failures

A faulty compressor or fan can prevent your AC from cooling effectively. When the compressor, which acts as the heart of your AC system, or the fan responsible for circulating air fails, your AC simply won’t cool your home properly.


  • Schedule a professional inspection to identify the issue.
  • A certified technician will repair or replace the faulty components to restore optimal cooling.

Don’t wait too long! Mechanical failures can lead to higher energy bills and more extensive damage. A quick call to a trusted technician will have your AC back in action, keeping you cool all summer long.


Cooling issues can stem from simple thermostat problems to more complex mechanical failures. A miscalibrated thermostat, frozen evaporator coil, or clogged air filter could easily explain why your AC isn’t cooling properly. If you’ve checked these common problems and your air conditioner is still underperforming, consider a leaky ductwork or low refrigerant levels as potential culprits. Also, ensure your AC is properly sized for your space and that the outdoor condenser unit is clean.

Mechanical failures like a faulty compressor or fan can also be to blame, requiring professional intervention. In these cases, it’s crucial to schedule a comprehensive inspection and repair to restore your AC’s performance.

If these quick fixes don’t resolve your issue, contact All Pro Heating, Air & Plumbing for complete AC maintenance and repair services in Indianapolis and surrounding areas. Our certified technicians are ready to help you get back to a cool, comfortable home. Send us a message, or call All Pro at 463-240-3355 for comprehensive AC repair and maintenance. We’ll do whatever is necessary to get your AC to start cooling again.