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Your AC unit is the only thing standing between you and sweltering summer temperatures. As long as it keeps working, you’ll remain cool and comfortable, but even small issues can prevent it from cooling your home properly and leave you sweating day and night.
Unfortunately, because modern air conditioners are sophisticated appliances, they can suffer from a variety of different problems. We’ll share a few of the most common AC problems Michigan homeowners experience, to help give you an idea of what may be wrong with your unit.
The 11 Most Common AC Problems in Southeast Michigan
While AC units can suffer from dozens of different problems, the following 11 are some of the most common, putting them at the top of the checklist for professional HVAC technicians.
1. Dirty Filters
Clogged air filters are one of the most common causes of poor AC performance, especially during Michigan’s peak summer cooling season. Restricted airflow forces the system to work harder, leading to higher energy bills and unnecessary wear on components.
HVAC Pro-Tip: Don’t Ignore Weak Airflow
If your vents are blowing less air than usual, don’t assume it’s just your system “struggling with the heat.” Weak airflow is often an early warning sign of problems like dirty filters, frozen coils, or blower issues — and catching it early can help you avoid more expensive repairs later.
2. Frozen Evaporator Coils
Frozen coils often result from restricted airflow or low refrigerant levels. The former is often caused by dirty filters, while the latter can unfortunately be caused by system leaks. In either case, frozen coils prevent your system from effectively absorbing heat, which may leave you with weak airflow or warm air during hot, humid days.
3. Clogged Condensate Drain Lines
Michigan’s humid summers cause your AC to remove a significant amount of moisture from the air, which normally drains away through something called a condensate line. But if that line becomes clogged with algae or debris, water can back up into the system, potentially causing leaks, water damage, or automatic shutdowns.
4. Critter Damage
Small animals often seek shelter in outdoor AC units or ductwork during Michigan’s long, cold winters. This can cause damage to your HVAC system, but because you aren’t running the AC in the winter, you aren’t likely to notice. But once spring rolls around, you may discover things like chewed wiring, nests, or blockages that reduce your system’s performance.
5. Short Cycling
If your home has an oversized system or airflow issues, you may notice the AC repeatedly turning on and off — something HVAC pros call “short cycling”. In Michigan, this can be especially noticeable during mild spring and early summer days, when systems struggle to run efficiently thanks to the fluctuating temperatures.
6. Refrigerant Leaks
Refrigerant leaks reduce your system’s ability to cool effectively, which can be especially frustrating during humid Midwest summers. Left unaddressed, low refrigerant levels can cause long-term damage to the compressor and lead to expensive repairs, which highlights the importance of addressing issues quickly.
7. Blown Capacitors
Capacitors help start and run your AC’s motors, but they can wear out over time. This is especially common in Michigan, thanks to the combination of our long winters and high summer temperatures, which make your unit work especially hard. This kind of use can contribute to capacitor failure right when you need cooling the most.
8. Thermostat Failure
A faulty thermostat can cause inconsistent cooling or even prevent your system from turning on at all. In some Michigan homes, older thermostats or wiring issues become more noticeable during seasonal transitions, when you switch from using your heater to using your AC.
HVAC Pro-Tip: Check Around Your Thermostat
If your AC seems to be turning on and off at odd times, take a look at what’s around your thermostat. Direct sunlight, nearby lamps, or even electronics can throw off temperature readings and cause your system to behave erratically.
9. Post-Winter Startup Failure
After sitting idle through months of cold weather, AC systems are prone to startup issues in the spring. Problems like stuck components, electrical faults, and debris buildup are some of the most common causes of this issue, and they can all prevent the system from running properly when first turned on.
10. Compressor Failure
Your AC’s compressor is essential for circulating refrigerant; when it fails, your AC can’t cool your home effectively. In Michigan, years and years of seasonal stress — long idle periods followed by heavy summer demand — can contribute to compressor wear and eventual failure.
11. Dirty Condenser Coils
Outdoor condenser coils can collect dirt, pollen, and debris, especially during Michigan’s spring and early summer. When coils are dirty, the system can’t release heat efficiently, leading to reduced performance, higher energy use, and increased risk of overheating.
HVAC Pro-Tip: Watch for Cottonwood “Fluff”
Cottonwood trees often release seeds and the associated “fluff” between May and June here in Michigan. This often leaves everything — including your outdoor HVAC unit — covered in a layer of hair-like material, which can reduce your HVAC’s efficiency by up to 50% in some cases. So, if you see cottonwood fluff collecting on the outside of your unit, turn the power off and gently rinse it with a garden hose.
How to Keep Your AC in Good Working Order: Seven Steps to Success
While any of these problems can ruin your day, there is some good news: Many of the most common AC problems Michigan homeowners face are preventable. With a little routine maintenance and attention (especially before or during seasonal transitions), you can keep your system running efficiently and avoid costly breakdowns during the hottest days of summer.
1. Replace or clean your air filter regularly.
Check your filter every one to three months during the cooling season, and more often if you have pets or live in a high-pollen area. Clean filters keep air moving properly through the system and reduce strain on critical components.
2. Schedule annual professional maintenance.
A spring tune-up is especially important in Michigan, as systems typically sit idle all winter. A technician can inspect your unit’s electrical components, check refrigerant levels, clean the coils, and catch small issues early.
3. Keep the outdoor unit clean and clear.
Leaves, grass clippings, and cottonwood fluff can quickly build up around your condenser unit in late spring and early summer. Make sure there’s at least 2 feet of clearance around the unit and gently rinse the coils if they become dirty.
4. Pay attention to drainage.
Your AC removes a lot of moisture during humid Michigan summers, so it’s important to keep the condensate drain line clear. Periodically checking for clogs can help prevent water damage and unexpected shutdowns.
5. Test your system before peak heat arrives.
Don’t wait until the first 90-degree day to turn on your AC. Run it for a short period in the spring to make sure it’s cooling properly and address any issues early.
6. Use your thermostat wisely.
Avoid constantly adjusting the temperature, which can lead to short cycling and unnecessary wear. A programmable or smart thermostat can help maintain consistent temperatures and improve overall efficiency.
7. Listen and look for early warning signs.
Unusual noises, weak airflow, inconsistent temperatures, or higher energy bills can all signal a problem. Addressing these early can often prevent more serious and expensive repairs later on.
AC Not Working? Dynamic HVAC Can Help!
No matter why your AC isn’t working, it’s always a good idea to have a professional take a look. This will not only allow you to get the AC repairs you need, but it may also reveal small issues you’ll want to address before they become big (i.e., expensive) problems.
The heating and cooling experts at Dynamic HVAC would love to evaluate your AC, provide any repairs you need, and make recommendations for the ongoing maintenance of your system.
We’ve been providing AC repairs across Southeast Michigan for more than 20 years, while earning impressive ratings on Google, Facebook, and Yelp, and an A+ rating from the Better Business Bureau. Contact us today to see why countless homeowners and property managers in the area have already trusted us to provide the AC repairs they need.
