Common AC Problems (and How We Fix Them Fast)

At Ashley Brothers Heating & Cooling, we know just how important a functioning air conditioning system is—especially during those sweltering summer months. Whether you’re at home or running a business, when the AC starts acting up, it quickly turns into an uncomfortable (and sometimes even dangerous) situation. Fortunately, most common AC problems can be fixed quickly and efficiently—if you know what to look for and have the right team on your side. In this post, we’re pulling back the curtain on the most frequent issues our technicians see in the field, and how we resolve them fast so you can stay cool and comfortable.

When Your AC Won’t Turn On

One of the most common issues our customers call us about is a unit that simply won’t turn on. If you’re wondering “why is my ac not working?”—this is often the first sign. Several factors could be at play here, and our experienced technicians always begin by checking the basics: thermostat settings, power sources, and circuit breakers. Believe it or not, a tripped breaker or dead thermostat battery is often the culprit.

If the power supply isn’t the issue, we then look into deeper mechanical problems such as a failed capacitor, blown fuse, or malfunctioning contactor. These are critical components that regulate how and when your air conditioner powers on. Our team carries a full inventory of replacement parts to ensure we can swap out faulty pieces on the spot, eliminating long wait times and keeping your home cool.

Because we know every hour without AC is a big deal, Ashley Brothers Heating & Cooling is structured for rapid response. Our trucks are stocked, our techs are trained, and our dispatch system is designed to get us to your doorstep as quickly as possible.

AC Blowing Warm Air

Another frequent concern we hear is that the air conditioning unit is running—but it’s blowing warm air instead of cool. This frustrating problem can have a few different causes. One of the most common is restricted airflow, typically due to a dirty air filter or a blocked return vent. During a service call, our team checks the entire air pathway, replacing filters and clearing blockages to restore full function.

Another potential issue is a refrigerant leak. Refrigerant is the lifeblood of your cooling system, and if levels drop too low, your AC simply can’t cool the air. Signs of a leak include hissing noises, frozen coils, or reduced airflow. If we suspect a refrigerant issue, we’ll run diagnostic tests to locate the leak, seal it properly, and recharge the system to manufacturer specifications.

Compressor problems and faulty thermostats are also suspects in this scenario. Our comprehensive diagnostic tools allow us to determine exactly what’s wrong without guesswork, giving you an accurate quote and a clear repair plan on the spot.

Strange Noises from the Unit

Air conditioners should be heard, not noticed. A slight hum or the sound of rushing air is normal—but if your unit starts to grind, squeal, rattle, or buzz, it’s time to call the pros. Odd noises are often the first sign of a part that’s wearing out or already broken.

Grinding noises often indicate a problem with the motor bearings. Squealing could mean a belt is loose or worn. Rattling might point to loose hardware or debris inside the unit. Buzzing can stem from electrical issues, including a failing capacitor or a contactor that won’t engage properly. These types of problems rarely go away on their own and usually get worse with time, so fast intervention is key.

At Ashley Brothers Heating & Cooling, we prioritize these service calls because we know the sound is more than just annoying—it’s a signal of deeper trouble. We’ll isolate the sound, identify the faulty part, and either repair or replace it on the spot. In most cases, we can restore your AC to full function during the same visit, thanks to our commitment to fully stocked vehicles and trained staff.

Water Leaks and Drainage Issues

It’s not unusual for homeowners to call us in a panic after noticing water pooling around their AC unit. Although it may seem alarming, this is actually a common and usually fixable problem. Most AC systems create condensation as part of the cooling process, and that water is typically channeled away through a drain line. If that line becomes clogged, broken, or disconnected, you’ll end up with water where it shouldn’t be.

When we respond to these calls, our first step is inspecting the drain line and clearing any obstructions—often caused by dirt, mold, or algae buildup. In more severe cases, we may need to replace the line or address issues with the drain pan. If left unchecked, drainage issues can lead to mold growth, water damage, and even electrical hazards, so we take every leak seriously.

We also check the evaporator coil for freezing, which can cause overflow when it thaws. If we find frozen coils, that typically indicates restricted airflow or low refrigerant—both of which we’ll resolve as part of the same service. That’s one of the key reasons why our customers trust our ac repairs: we get to the root of the problem instead of applying temporary fixes.

Uneven Cooling Throughout the Home

Have you ever walked from one room into another and felt a dramatic difference in temperature? Uneven cooling is one of the more subtle but persistent AC problems we fix. This often happens due to issues in the ductwork—such as leaks, blockages, or poorly designed layouts that fail to deliver balanced airflow.

Our team uses airflow meters and infrared technology to diagnose these inconsistencies. If we find leaks in your ductwork, we’ll seal them with professional-grade materials. If poor design is the issue, we’ll recommend and implement adjustments to balance your system better. In some cases, the issue is with zoning, or the need for better thermostatic control in larger homes. We can install smart thermostats and zoning systems to give you precise control over each area of your home.

Sometimes, the root cause is as simple as a neglected air filter or an AC unit that’s not appropriately sized for your space. During every call, we conduct a full system evaluation to ensure your cooling setup is optimized for efficiency and comfort. Our air conditioning tips are always customized to your home’s layout and your lifestyle needs.

Preventative Maintenance: Our Best Fix is the One You Don’t Need

While we pride ourselves on being fast and efficient at solving problems, we’re even bigger believers in stopping them before they start. One of the best things you can do for your AC system is to invest in routine maintenance. Our preventative maintenance services are designed to catch small problems before they become big repairs—and keep your system running smoothly all season long.

During a typical maintenance visit, we’ll inspect every component of your system: from refrigerant levels and electrical connections to fan motors and filters. We’ll clean the coils, test for efficiency, and make minor adjustments that can extend the life of your unit. You’ll get a full report on the condition of your system and practical advice on how to fix ac problems before they interrupt your comfort.

Many of our clients sign up for our seasonal maintenance plans, which include priority scheduling, discounted repairs, and peace of mind that your AC is ready to handle even the hottest days. If you’ve ever asked yourself “why is my ac not working” in the middle of July, you know the value of being proactive.

Conclusion

At Ashley Brothers Heating & Cooling, we believe in service that’s fast, friendly, and always focused on long-term value. Whether it’s your first time calling us or you’ve been with us for years, we treat every home like it’s our own—and every system like it’s mission critical. When you need ac repairs, we’re just a call away.

We’re here to keep your home comfortable, your AC running at its best, and your summer stress-free. Stay cool—and remember, the sooner you call, the faster we fix it.

Need HVAC Services in St. Louis, MO?

Keep cool or stay warm with Ashley Brothers Heating & Cooling. Since 1999, Ashley Brothers have been providing residential and commercial services to the St. Louis and Jefferson County area. We specialize in the installation of new equipment, heating and cooling repair, and furnace cleaning. Craftsmanship is important, equipment choice is too. We work with only top brands like Amana, Goodman, York, and McLain. It is understandable that replacing or upgrading your equipment can be daunting. Ask us about financing. We repair all heating and cooling equipment brands. Heating and cooling repairs can happen at random, take advantage of our 24-hour emergency service. Call us today about your concerns.