Bad Condenser Fan Motor?
What should your next step be?
Maybe you noticed that your condenser fan is no longer turning, or an AC repair service company recommended replacing the fan motor in your AC unit. Either way, you need to know what a condenser fan is, what it does for your HVAC system, and what options you have. Continue reading this article we will give you all the information that you need to know when dealing with condenser fan motors.
Air Conditioning Fan Motors
There are two main types of HVAC motors: the outdoor unit (condenser) and the indoor air handler (evaporator). Condenser fans help dissipate heat from the high-side refrigerant inside the condenser coil, and the ac fan motor plays a crucial role in this process. In an air handler, fans, also called a blower motor, are used to circulate air through the evaporator coil and throughout a conditioned space.
Regular maintenance of ac fan motors is essential to ensure efficient operation and prevent potential issues. To create efficient air movement, the fan assembly is typically housed in sheet metal or plastic so that it draws air from a specific area and moves it to a specific area.
Fans are carefully balanced and should run with little noise. A fan is usually connected to a motor shaft with setscrews. The fan motor may be attached to brackets and mounted with rubber grommets. Generally, motor leads from the power source to the condenser fan are connected to the common terminal and the running terminal of a compressor motor. This connection puts the fan motor in parallel with the compressor motor and allows it to be controlled by the thermostat. When the compressor runs, the condenser fan motor also runs.
What is a Condenser Fan Motor?
What is a condenser?
A condenser is going to be installed along the outside of your home. These are commonly referred to as the air conditioner or heat pump. Normally they are a large box shape. It will have a fan mounted to the inside of the top and it will be connected to your house by a piece of conduit and two copper lines.
You may not have a condensing unit; you may have what is referred to as a package unit. Where your entire air conditioning and heating system sits outside in one package, instead of having half outside and half inside. These will normally be much larger than a traditional condenser and have ductwork attached to it that penetrates your home. These units will still contain a condenser fan found mounted to the top of the unit, even if it may be in a slightly different fashion.
The Condenser Fan Motor
The condenser fan motor is the large fan motor attached to the top of the inside of the condenser. It has a single shaft protruding from it, and generally a two or three-sectioned fan blade connected to the shaft. This motor will turn on every time the condenser turns on and will blow air out the top of the unit.
This motor’s job is to pull cold air through the hot coils of the condenser, cooling the coils off and blowing the resulting heated air out of the top, ensuring the efficient operation of the ac's fan motor. If you have ever felt the air blowing out of the top of your condenser this is why it is so warm.
Without the condenser fan running, the air is unable to move across the coils to cool off the freon inside of your air conditioning system. This can cause your system to overheat, you will have very little to no cool air coming into your home, and if left unchecked it can result in catastrophic failure of your equipment.
Your unit will have certain ways to protect itself against complete failure, but it is best to find and fix the problem as soon as possible to reduce the risk of further damage. If you have a bad ac fan motor, it can lead to overheating and reduced cooling performance.
If your condenser fan motor has failed, it is generally easy to notice. You will be able to hear your compressor running, but the fan blades will not be turning. Sometimes there can be other problems with the fan though. For example, it could still be turning but making grinding noises or loud screeching, which may indicate that the bearings have worn out. Maybe it has become off-balanced and has vibrated your condenser to the point that the fan or fan motor mount is coming apart. Or maybe your fan has developed issues that are beginning to pose a threat to the health of your condensing unit. Whenever a fan motor’s structure, mount, or fan fails it can result in catastrophic damage being caused to the inside of your condenser.
How the Condenser Fan Motor Works
The condenser fan motor is a crucial component of your air conditioning system, playing a vital role in keeping your home cool. Located in the outdoor unit, the condenser fan motor works by drawing in air and blowing it over the condenser coils. This process helps dissipate the heat absorbed by the refrigerant, allowing the system to release it into the outside air.
When the air conditioning system is running, the condenser fan motor uses electrical energy to spin the fan blades attached to its shaft. As the motor operates, the fan blades turn at high speeds, typically between 1000 to 2000 RPM. This rapid movement draws in cooler air from the surroundings and forces it over the hot condenser coils. The heat from the refrigerant is then transferred to the air, which is expelled out of the top of the unit.
This continuous cycle of drawing in air and expelling heat is essential for the efficient operation of your air conditioning system. Without the condenser fan motor working properly, the refrigerant would not be able to release its heat, leading to an overheated system and reduced cooling performance.
Signs of a Bad Condenser Fan Motor
A bad condenser fan motor can significantly impact the performance of your air conditioning system. Here are some common signs that your condenser fan motor might be failing:
Irregular or No Operation: If the fan blades are not spinning or are spinning irregularly, it could indicate a problem with the condenser fan motor. This irregular operation can prevent the system from dissipating heat effectively.
Unusual Noises: Listen for any unusual sounds coming from the outdoor unit. Rattling, buzzing, or grinding noises can be a sign that the condenser fan motor is malfunctioning. These noises often indicate issues with the motor bearings or other internal components.
Reduced Cooling Capacity: If your air conditioning system is not cooling your home as effectively as it used to, a bad condenser fan motor could be to blame. Without proper heat dissipation, the system struggles to cool the air efficiently.
Overheating: An overheating air conditioning system is a clear sign of a condenser fan motor issue. When the motor fails to operate correctly, the system cannot release heat, leading to increased temperatures and potential system shutdowns.
High Energy Bills: A malfunctioning condenser fan motor can cause your air conditioning system to work harder than necessary, leading to higher energy consumption and increased utility bills.
Recognizing these signs early can help you address the problem before it leads to more significant issues with your air conditioning system.
Types of motor failures
Three general areas of fan motor failure are as follows:
Electrical problems with the motor windings:
Problems with the motor starting components
Mechanical problems with the motor
Motor winding failures include:
Open windings
Shorted windings
Shunted windings
Grounded windings
Starting and safety components that can fail and give the appearance of a defective motor are as follows:
Running capacitor
Starting capacitor
Potential relay
External overload
Internal overload
Mechanical problems include the following:
Bearing failure
Drive problems
Troubleshooting a Bad Condenser Fan Motor
If you suspect that your condenser fan motor is failing, a systematic approach to troubleshooting can help identify the root cause. Here are some steps to follow:
Check the Power Supply: Ensure that the condenser fan motor is receiving power. Check the circuit breaker or fuse box to make sure there are no tripped breakers or blown fuses. A lack of power can prevent the motor from operating.
Inspect the Fan Blades: Examine the fan blades for any signs of damage or wear. Damaged blades can hinder the motor’s ability to move air effectively. Clean the blades if they are dirty, or replace them if they are damaged.
Check the Motor Bearings: Worn or damaged motor bearings can cause the motor to operate inefficiently or make unusual noises. Inspect the bearings and lubricate them if necessary. If the bearings are severely worn, they may need to be replaced.
Examine the Capacitor: The capacitor helps start and run the condenser fan motor. If the capacitor is damaged or worn out, the motor may not start or run properly. Inspect the capacitor for any signs of damage and replace it if needed.
Inspect the Wiring: Check the wiring connected to the condenser fan motor for any signs of damage or wear. Damaged wiring can prevent the motor from receiving power or cause it to operate intermittently. Repair or replace any damaged wiring.
By following these troubleshooting steps, you can identify and address issues with your condenser fan motor, ensuring that your air conditioning system continues to run efficiently and effectively. If you’re unsure about any of these steps, it’s always best to consult with a professional HVAC technician.
Should you replace it with an OEM or Rescue motor?
A condenser fan motor replacement and all air conditioner repair work should always be performed by an HVAC professional. Your HVAC technician will sometimes give you the option of installing an OEM motor or a rescue motor. An OEM motor is just that, an Original Equipment-manufactured motor. These motors are made for your specific application, they will only have one RPM and one horsepower option.
OEM motors are going to be the most common condenser fan motors installed by service technicians for the AC fan. OEM motors generally must be ordered from a local distributor. Depending on the age and brand, these motors may not be in stock and take several days to receive. These are the most popular options. OEM motors come with manufacturer warranties and are generally easier to replace. However depending on the brand, the price of these motors is typically higher than the rescue motor. Typically, the customer seems to be a little hesitant about departing from the manufacturer’s recommended parts.
Rescue motors are manufactured with versatility in mind. These motors are made to be kept on a service truck in case almost any size of motor breaks down and needs to be replaced. They are designed to operate with a broad range of different horsepower, making them a very flexible option. One fan can be equipped for a 1/6th HP to a 1/3rd HP capacity. The Rescue brand motors have also stepped up their technological game with higher efficiency replacement models as well.
These motors require some specialized knowledge to install and will sometimes have to be programmed for your specific application. One drawback could be that OEM motor shafts extend
to a specific length based on enclosure design. Installation of a rescue motor may affect the operating characteristics of your unit. Rescue motors are a great option for a temporary repair, especially if the OEM motor is not available for a few days. The negative here is that you end up paying the labor costs twice.
How much does it cost to replace a condenser fan motor?
The big question for every customer is, “What is this going to cost?“ The typical from every question AC company is, “It depends.” There are as many prices as there are types of condenser fan motors, and the location of the condenser unit can also affect the cost. The cost of the motor is the biggest variable. For each type and brand, the price will vary. Most HVAC companies have a standard fee for replacing the motor, and labor costs. There will be a small amount of material charge, wire nuts, tape, etc. No special tools are needed. Some companies charge a diagnostic fee for troubleshooting the issue. Some other factors that might affect the price:
Location of the outside unit
Difficult access (i.e. crawlspace)
Enclosure design
Single-phase or three-phase
Final Thoughts
Now you know what condenser fan motors are, and where to find them. You know what to look for if you suspect that a bad fan motor may be to blame for your air conditioner not working. You should be able to give your AC repair company a good idea of what the problem may be when you give them a call. A condenser fan motor might be an easy thing to self-diagnose, but it is not necessarily something that an average homeowner should attempt to replace. There are dangerous moving parts and voltage involved. It is always best to call a professional and have them diagnose and replace potentially dangerous items.
