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Serving West Austin & Surrounding Areas

Most Common AC Problems | Common Ways Air Conditioners Break Down

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If you suspect that your AC needs a repair, whether it isn’t cooling as effectively, you’ve noticed funny sounds, or something else seems off, you may be wondering what the issue could be. Having an idea of what you might expect from a professional diagnosis could help you anticipate costs, discover potential DIY solutions, or simply learn more about prevention.
This post will help you understand some common reasons air conditioners stop working, the early warning signs, and techniques for proactive prevention.

1. Capacitor Issues

Your air conditioner needs far more energy than is available via your home’s built-in wiring to start up. The AC’s capacitor or capacitors store the additional electricity required to start the unit’s motors, including the compressor motor, the outside fan motor, and the indoor fan motor.

Symptoms & Warning Signs of a Failing Capacitor
If the capacitor is failing or not receiving the correct voltage, the entire cooling process will be impaired. You’ll notice that the AC isn’t blowing cold air, the AC is struggling to kick on and is turning off frequently, a humming noise, a sudden and drastic increase in your electricity costs, or the system might fail to turn on at all.

Reasons AC Capacitors Fail
Your capacitor might fail for a variety of reasons including old age, overheating due to weather or lack of maintenance, power surges, and physical damage to your unit.

How To Prevent Capacitor Failure
Capacitor failure is a common problem for aging, damaged, and undermaintained air conditioners. In fact, getting regular maintenance for your unit can prevent a variety of issues that contribute to a broken AC capacitor.
Maintenance proactively addresses problems known to result in overheating, including dirty filters, refrigerant leaks, and grimy condenser coils. Maintenance also ensures that your AC voltages are correct and that your electrical connections are secure and uncorroded.

2. Refrigerant Issues

Your AC works by taking hot air from inside and distributing it outside. To do this it uses refrigerant, a chemical that cycles through your AC’s coils, thereby absorbing and releasing heat.

Symptoms & Warning Signs of a Refrigerant Problem
Since your refrigerant is essential for the cooling process, one of the most common telltale signs of an issue with your AC’s refrigerant is poor cooling or low airflow. If you live in a humid climate, you’ll likely also notice that your home feels more sticky.
Other common signs of a refrigerant leak include hissing sounds coming from the unit, leaks in the attic or around your closet unit, spikes in electrical costs, and ice on your evaporator coil, which can be caused by several other factors. Learn more about these other factors now.

Reasons AC Units Experience Refrigerant Issues
If you just had a new unit installed and are experiencing issues, the installation tech may have charged your AC incorrectly. However, since most units come pre-charged, the issue is more likely caused by flawed factory assembly or handling, or by vibrations caused by improper in-home installation
If your AC isn’t new but you suspect a refrigerant leak based on the above symptoms and warning signs, your problem was likely caused by corrosion of the copper tubes inside your coils, corroded or weakened connections, and other wear and tear.

How To Prevent Refrigerant-Related Problems
While some factors leading to refrigerant leaks are out of your control, the factors within your control are much more likely. Corrosion, weakened connections, and signs of wear and tear can all be monitored and corrected with yearly maintenance. Our maintenance program is designed to detect and repair small leaks, signs of corrosion, and electrical issues before they have a chance to cause further damage.
Can I add more refrigerant on my own?

Don’t pass up maintenance or ignore the early signs of a refrigerant leak as this can lead to additional damage of other vital AC components.
Furthermore, if you give you dogs free roam of your hard, we recommend adding a gate to keep your AC unit inaccessible. Dog urine is highly corrosive and it’s not uncommon to see damaged refrigerant coils as a result of dog activity.

3. Dirty Filters

We commonly think of air filters as air purifiers; a way to protect ourselves and our families from airborne contaminants such as dust, pollen, viruses, and more. But unless you’re installing specialized filters designed to capture microscopic particles, a regularly maintained filter is actually for the benefit of your HVAC system.

Symptoms & Warning Signs of a Neglected Filter
A filter that’s clogged and no longer trapping dirt or dust can quietly wreak havoc on your AC system. A filter that’s unable to trap dust will allow those particles to travel through your ductwork and into your AC’s sensitive internal components. This can lead to increased mold growth, clogged condensate lines, dirty evaporator coils, and compressor malfunction.
Additionally, a dirty filter significantly restricts airflow. When airflow is impeded, it doesn’t just mean decreased comfort for you. Lowered airflow makes it more difficult for your entire unit to work efficiently. This will initially lead to increased energy bills, but ultimately, you’re looking at early wear and tear due to overheating, short-cycling, damage to the evaporator coils, and more.

Reasons Dirty Air Filters Are Common
Perhaps the most common reason for air filter neglect is that many homeowners haven’t understood the scale of the impact a couple of dirty filters can have on an AC system. Other contributing factors are inconvenience and money.

How To Prevent Dirty Filters
Knowing the extent of problems dirty filters can cause, we recommend making the time to replace your filters at least once a month in the summer or whenever your system is frequently in demand.
A standard-grade 1-inch filter that’s sufficient enough to protect your system can be purchased for less than $5 at your local supermarket or home improvement store. A quality-performance washable filter you can reuse for life can also save you thousands while costing less than what you likely spend gassing up your family vehicle.

4. Dirty Coils

Your AC’s evaporator coils are responsible for removing the heat from your home’s air. The condenser coil is responsible for releasing the heat into the outdoors. Since the condenser coil is located outdoors and exposed to the elements, it can easily accumulate debris. However, both coils are susceptible to dirty buildup from dust and other airborne particles.

Symptoms & Warning Signs of Dirty AC Coils
When dirt builds up on your AC’s coils, heat can’t be taken in or escape as effectively. This initially results in poor cooling, higher energy bills, and an AC that’s always running.
Since dirt restricts heat absorption, dirty evaporator coils can cause refrigerant temperatures to drop too low, leading to condensation and ice. Ice on your unit can dramatically reduce AC efficiency, but when left unattended, it can lead to overheating and complete breakdown of the unit.
Because your system has to work harder to cool your home to the set temperature, dirty condenser coils are responsible for increased wear and tear and early system failure when left uncorrected.
Additionally, because your evaporator coils naturally drip off excess water, dirt on the coil can cause clogs in your condensate drain line.

Reasons AC Coils Get Dirty
Try as we might, we can’t completely prevent our AC’s exposure to dirt, dust, and debris. The outside unit is particularly susceptible to being coated in gunk due to its constant exposure to the elements, foliage, grass clippings, and so on.

How To Prevent Dirty AC Coils
You can clean the coils yourself if you have some training, know-how, and the right cleaning equipment. However, be warned that the process is fairly time-consuming if you’re not well-versed in HVAC maintenance.
The easiest and most effective way to keep your evaporator coils clean is by changing your filter on a regular basis, and scheduling professional maintenance twice a year.

5. Clogged Drain Lines

Since the natural process of removing heat from your home via the evaporator coil creates condensation, your AC needs a condensate line to flush all that water out. When your condensate line becomes clogged, the accumulation will have nowhere to run off to.

Symptoms & Warning Signs of Clogged AC Drain Lines
When your AC line gets clogged, water will begin to back up into your house. Your AC’s drip pan is designed to catch water leaks, and it may have an emergency shut-off switch triggered by accumulating water.

Reasons AC Lines Clog
Dust and dirt that builds up on your evaporator coil can easily be carried off with condensate and end up lodged in your drain, eventually clogging your line.

How To Prevent Clogged Condensate Lines
A high-quality filter and regular maintenance to keep your coils clean will go a long way to prevent lines from clogging.