AC Fan Not Spinning? Quick Troubleshooting and Solutions
It can be frustrating when your AC fan isn’t turning. Learn common causes and tips to fix the issue and get your AC up and running efficiently.
It’s a fact that global temperatures have risen each year. And so when the warmer months come along, air conditioning (AC) units have become invaluable in keeping our homes and office cool and comfortable.
But air conditioner problems like the AC fan not working can arise at any time, and this can often lead to costly repairs on top of the inconvenience.
While it’s possible to fix AC system or AC fan problems yourself, the better option is to contact a professional like Air Worth to help you. With a professional air conditioning service, you can rest assured that your AC unit is in capable hands. However, it’s still helpful to know what you can do if hiring professionals may not be a feasible option.
How the AC Fan Works
Let’s begin by understanding the different parts of an air conditioner:
- Compressor unit: This is the heart of the AC unit that is responsible for circulating the refrigerant through the system. It turns low-pressure, low-temperature refrigerant gas into a high-pressure, high-temperature gas.
- Condenser Coil: This functions as a heat exchanger located in the outdoor unit, which receives the high-temperature refrigerant from the compressor. As it condenses into a liquid state, it releases heat to the outside environment.
- Expansion Valve: The expansion valve reduces the pressure and temperature of the refrigerant, allowing it to expand into a low-pressure, low-temperature vapor.
- Evaporator Coil: This is another heat exchanger that absorbs heat from the indoor air, cooling it down in the process.
- Air filter: The filter is located in the evaporator, and it helps remove dust and other particles from the air before it’s cooled.
- AC fan: Also known as an air handler, it plays a crucial role in the cooling process of an air conditioning system. It is typically located indoors and works in conjunction with the outdoor condenser unit.
Now, onto how the AC fan motors work. The primary purpose of the AC fan unit is to dissipate the heat absorbed from inside the building by the refrigerant.
The different parts of the fan are the following:
- Fan motor
- Fan blade
- Fan axle
When the refrigerant circulates through the AC system, it carries the heat from the indoor evaporator coil to the outdoor condenser coil.
The AC fan draws ambient air across the condenser coil, facilitating the transfer of heat from the refrigerant to the outdoor air. As the hot refrigerant releases its heat, it condenses back into a liquid state, preparing it to repeat the cooling cycle.
The fan’s continuous operation ensures a steady flow of air across the condenser coil, maintaining efficient cooling and allowing the AC system to regulate indoor temperatures effectively.
Now let’s take a look at how the AC unit’s fan works in different air conditioning systems:
Window Type Air Conditioner
In a window-type unit, the fan is usually found in the front. It’s a centrifugal fan that works just like the fans in any other air conditioner unit.
It circulates the air through the evaporator coil, which is cooled by a refrigerant. As the air passes over the coils, the heat from the air is absorbed into the refrigerant. This cools the air and it is then circulated throughout the home.
In this system, the main difference is that there are two fans are being used: centrifugal and axial fans. Both fans circulate air through the evaporator and condenser coils.
Centrifugal fans have blades that spin around an axis while axial have blades that spin parallel to the airflow. This creates a straight stream of air that’s circulated through the coils.
The combination allows this air conditioning system to have improved airflow and reduced energy consumption.
Common Reasons for AC Fan Not Working
When the air conditioner fan fails to work properly, it will severely affect the performance of the AC unit. From an AC fan not spinning to not blowing cool air, there are various reasons for the fan to not work properly.
Here are some of the common reasons you may encounter:
Why Your AC Unit Fan Isn’t Turning On
- Electrical issues: This can be caused by a variety of reasons like a blown fuse, a tripped circuit breaker, faulty wiring, or a power surge.
- Broken fan belt or drive system: In certain AC units, a belt or drive system connects the fan motor to the fan blades. If it’s broken or loose, the fan won’t spin.
- Faulty thermostat: The thermostat may not be set correctly or could be malfunctioning, preventing the fan from activating.
- Faulty capacitor: The fan motor’s capacitor, which provides a jolt of energy to start the fan, may be faulty or worn out.
- Defective AC fan motor: The fan motor itself could be faulty, preventing it from operating even if power is reaching it.
- Blocked fan blades: Dirt, debris, or ice can block the blades and prevent the fan from spinning.
Why Your AC Unit Fan Isn’t Turning Off
- Thermostat problems: A malfunctioning thermostat may be stuck in the “ON” position, so it continues to run even when the desired temperature has been reached.
- Defective AC fan motor: If you have a bad fan motor, it can also cause the fan to keep running.
- Stuck fan relay: The relay is an electrical component that controls the fan’s operation. When this fails or gets stuck, it can leave the fan continuously powered.
- Wiring issues: There may be issues with the wiring system that connects the thermostat to the fan.
- Sensor failure: Many ACs have a safety switch or a sensor that monitors the various parts of the system. When this fails to work properly, it can prevent the fan from working.
- Clogged air filter: When this happens, it restricts airflow and prevents the fan from working properly or not working at all.
Troubleshooting Steps: DIY Solutions
Step 1: Clean the Air Filter
- Turn off the AC unit: Before attempting to clean the air filter, switch off the AC unit to ensure safety.
- Locate the air filter: Find the air filter panel, usually situated near the return air duct or on the indoor unit.
- Remove the air filter: Carefully remove the filter from its slot. Note the direction of airflow indicated on the filter’s frame.
- Clean the filter: Gently vacuum or rinse the filter under cool water to remove dust and debris. Let it dry completely before reinserting.
- Reinstall the filter: Put the clean, dry filter back into the designated slot, following the airflow direction.
Step 2: Check the Fan Capacitor
- Turn off power: Ensure the AC unit is disconnected from power to avoid electrical hazards.
- Access the capacitor: Locate the capacitor, usually inside the outdoor condenser unit, near the fan motor.
- Discharge the capacitor: Using an insulated screwdriver, carefully short the terminals to discharge any stored electrical charge.
- Test the capacitor: Use a multimeter set to capacitance mode to check the capacitance value. Compare it to the manufacturer’s specifications.
- Replace if faulty: If the capacitor shows a significantly lower value or is entirely open, it may be faulty and should be replaced.
Step 3: Inspect the Fan Motor
- Turn off the power: Disconnect the power supply to the AC unit to ensure safety during inspection.
- Access the fan motor: Locate the fan motor, often found in the outdoor condenser unit behind the protective cover.
- Check for physical damage: Inspect the motor for any signs of physical damage, such as bent blades or loose connections.
- Lubricate if applicable: Some fan motors have lubrication ports. If applicable, use the recommended lubricant to maintain smooth operation.
- Test the motor: Reconnect the power and turn on the AC unit. Listen for any unusual noises or vibrations that may indicate motor issues.
Step 4: Check for Power
- Verify power supply: Ensure the AC unit is correctly connected to a power source and that the circuit breaker is not tripped.
- Check thermostat settings: Make sure the thermostat is set to “cool” and the fan mode is set to “auto” to avoid continuous fan operation.
- Inspect wiring and connections: Visually examine the electrical wiring and connections for any signs of damage or loose connections.
- Test voltage: Use a multimeter to check for voltage at the fan motor terminals. There should be a voltage reading when the AC is running.
- Call a professional if needed: If all DIY checks are unsuccessful, it’s best to contact a qualified HVAC technician for further diagnosis and repair.
Remember, if you are not comfortable or familiar with electrical components and troubleshooting, it’s always best to seek professional help, like tapping into Air Worth’s AC repair services, to avoid any potential hazards or further damage to the AC unit.
When to Seek Professional Help
While fixing your air conditioning fan yourself can be gratifying, there are times when you need professionals to step in. Save yourself the trouble and call your trusted technicians when you encounter these situations:
- Your AC is not blowing cold air. This is the most obvious sign that your AC needs to be repaired. If your AC is not blowing cold air or it’s not as cold as it used to be, then it’s no longer functioning properly.
- Your AC is making strange noises. Some humming sounds are normal, but strange noises can be a sign of various problems like a failing fan motor, a bad compressor, or a refrigerant leak.
- Your AC is leaking water. Water leaking from your AC can mean several things including a clogged condensate drain, a bad evaporator coil, or a refrigerant leak.
- Your AC is not turning on. We’ve listed above the different reasons why your AC isn’t turning on. If you’ve tried troubleshooting but it still won’t work, there might be a more serious issue that only a professional can diagnose and fix.
- Your AC is not cooling your home properly. The air conditioning unit is meant to cool your home to comfortable levels. If it’s not doing its job, it could be caused by a dirty air filter, a low refrigerant level, or a problem with the compressor.
Preventive Maintenance Tips: How to Prevent AC Fan Problems
As the saying goes, prevention is better than any cure. Keeping your AC fan in top shape will save you from headaches, and additional expenses, and ensures your unit’s longevity.
Here are some tips to prevent AC fan problems.
- Regular maintenance: Have your unit maintained by competent technicians regularly. This way, they can clean, inspect, and replace any parts to keep your AC in good working condition.
- Replace air filters regularly: By doing so, you can keep the air flowing properly without any obstructions, allowing the fan to do its work efficiently.
- Keep the outdoor unit area clean: Remove any debris, dirt, vegetation, and any obstruction on and around the outdoor unit, especially around the fan and the condenser coil. This will give proper airflow and prevent overworking the unit.
- Check and clean the condenser coil: Related to the previous tip, make sure you clean the condenser coil and that it’s free from dirt, dust, and debris that have accumulated over time to ensure you have unobstructed airflow.
- Investigate weird or unusual noises: If you hear anything that’s not normal for your AC fan, don’t dismiss it as they’re often signs of problems with the fan or unit.
- Avoid overworking your AC system: It’s tempting to set the thermostat too low on extremely hot days. However, this can strain the system and lead to fan and compressor problems.
Get Your Air Conditioning Unit in Top Shape
An air conditioning unit isn’t just for keeping you cool on hot days; it helps you lead a life of quality and comfort. So don’t take it for granted and make sure it’s always in top shape.
When it’s time to get professional help, Air Worth is a trusted name when you need an experienced HVAC technician, whether it’s for your home or place of business.
With more than 25 years of serving the Texas community, we’ve provided the best quality AC repair and maintenance services. And in the process, we’ve built strong relationships where customers rely on our expertise to help them lead the way of life they deserve.
Contact us now to have a local HVAC professional service or repair your air conditioning system.