The condenser fan is located in the outdoor AC unit and is an essential part of an AC system. While this fan usually lasts for at least 10 years, its motor can end up wearing out before the outdoor unit itself fails.
If the motor does wear out and the fan no longer spins, it can lead to numerous issues and potentially cause major damage. Here, we’ll explain what role the fan serves and the signs that can help you know if the fan motor is bad and you need to have it replaced by a local AC repair professional.
Understanding the Role of an AC Condenser Fan
The condenser fan serves two important and interrelated purposes. When the system is running, the fan continually pulls air into the outdoor condenser unit so that it constantly blows over the condenser coil. As the air blows over the coil, it absorbs heat from the refrigerant flowing through the coil so that it quickly cools down and its pressure decreases.
If the fan isn’t working or isn’t drawing in enough air, the refrigerant pressure and temperature will remain much too high for the AC system to cool effectively. The heat and high pressure can also result in the compressor overheating and triggering the thermal protection switch, causing the compressor to shut down. Even though the compressor should shut down if it overheats, there’s still a chance it may get damaged. Overheating has the potential to damage electrical components as well.
Signs That Your Condenser Fan Motor Is Worn Out
You may notice that your AC is putting out warm air or not cooling as effectively as it normally does. If so, one thing you should do is go outside and check to see if the condenser fan is spinning. If you can hear the compressor running but the fan isn’t spinning, the next step is to go back inside and shut your AC off at the thermostat.
You then want to go back outside and check to make sure the fan blades aren’t obstructed by a stick or anything else. You can also check if the fan is obstructed by using something like a screwdriver to see if you can get the fan blades to spin.
If the blades spin freely but the fan still won’t come on when you turn your AC back on, it usually means that either the fan motor or the start capacitor is bad. The capacitor is essentially a large battery that provides the extra power and torque the fan motor needs to turn on.
The fan motor won’t be able to start if the capacitor fails. While capacitors sometimes last for the life of the AC system, they can end up failing in as little as five to 10 years—especially if there are any electrical issues.
Another issue to watch out for is if the fan only works intermittently or starts spinning when the compressor turns on and then turns off almost immediately. The first issue can indicate that the fan motor is beginning to wear out, one of the electrical connections is loose or one of the wires is damaged. If the fan only runs for a short time when the outdoor unit comes on, it almost always means the motor is worn out.
If the fan blades are spinning slowly, it usually indicates that the motor is beginning to wear out and will soon fail. However, it can also be a sign that the bearings are worn out. In that case, you’ll only need to have the bearings replaced and not the fan motor itself. Worn-out bearings can lead to the fan not shutting off when the rest of the system does as well.
Another way you can tell that the bearings are starting to wear out is if the fan makes a loud screeching or squealing sound as it runs. If you hear this noise, it’s essential that you get your AC inspected as soon as possible or else the fan motor could burn out. Replacing the fan motor isn’t terribly expensive, but it will cost quite a bit more than just replacing the bearings.
A loud rattling noise can happen because of loose components, but it can also be another sign that the fan motor is wearing out. One last thing to watch out for is if your AC frequently trips the circuit breaker. This can happen because of an electrical issue, but it can be a sign that the fan motor is wearing out and drawing too much power as well.
How Professionals Test for a Bad Fan Motor
Unless you’re an electrician, an HVAC technician or otherwise have extensive knowledge of electrical equipment and wiring, it’s extremely difficult to test the fan motor to determine if it’s worn out. Also, the issue may lie elsewhere.
When professionals are trying to diagnose condenser fan issues, they perform what’s known as a continuity test. This involves using a multimeter to measure ohms and check the resistance between the white wire and the three other wires. If the resistance is higher or lower than normal, it indicates that there’s an issue with one of the motor’s windings and that the motor is faulty and needs to be replaced.
If the resistance readings are normal, the technician will then move on to testing the capacitor to see if it’s worn out. Testing the capacitor is dangerous and could result in a serious shock if you don’t know what you’re doing and don’t take proper precautions by discharging the capacitor before you touch it.
How Maintenance Can Help Prevent Condenser Fan Issues
The biggest key to avoiding issues with the condenser fan and the rest of your AC system is to have a professional inspect and service the system once or twice a year. When inspecting the system, the technician will usually be able to tell if the fan motor, bearings or capacitor are starting to wear out and could lead to the fan suddenly not running. They’ll also lubricate the bearings and other moving parts as needed to prevent issues from arising.
During the inspection, the technician will look for any other problems that could lead to your AC breaking down or cause a major spike in the amount of electricity it uses as well. This includes things like dirty coils, a malfunctioning blower, a refrigerant leak, loose electrical connections, etc. In general, your AC system will experience fewer issues, work more efficiently and last longer if you make sure to keep it properly maintained.
Contact Us Today
For fast, reliable heating and cooling services in Anoka, MN, Liberty Comfort Systems is the company to look to. Our experienced technicians can repair and service all brands, models and types of HVAC equipment and will help make sure your home is comfortable all summer and winter long.
As a Lennox Premier Dealer, we also offer a range of excellent options if you need to replace your cooling or heating or are looking to upgrade to a more efficient system. If you’re dealing with a bad fan motor or any other problems with your HVAC system, give us a call and we’ll make sure to quickly and correctly fix the issue.
