3-Speed, 4-Wire Ceiling Fan Switch Wiring
Ceiling fans have a long lifespan, some ranging into decades. Depending on the manufacturer, the fan may have a lifespan of between seven and fifteen years. However, within that time, you may experience wiring problems that will need repairs. The wiring of ceiling fans can be quite confusing for those who do not know how they work. Let's look at how the fan works and how its switch should be structured.
Most ceiling fans use a motor known as the permanent split capacitor motor. With this type of motor, there are two capacitors that facilitate their running. One of the capacitors is a starter, while the other is a run winding. The capacitors are usually connected in series with the starter used to initiate movement. Once the motor is up and running at speed, it becomes an auxiliary winding.
To reverse the motor, the capacitor is applied to run winding which means it becomes the start winding capacitor. In most cases, the capacitors have taps that help control the levels of speed. In other ceilings, the values of start and run are lowered sequentially to provide different speeds. For some unique designs, you may find that additional capacitors are used in series with the motor to regulate speed.
Signs of a Bad Capacitor in a Ceiling Fan
If one of the capacitors in the fan is spoiled, your fan might start misbehaving. This does not mean that it will stop functioning completely. Your fan might still be functional even when it is spoiled. There are signs to look out for to determine when your fan capacitors are spoiled. These signs include:
- The fan runs slowly at all speeds
- The fan fails to run completely at all speeds
- The fan won't run but spins when started with a hand
- Certain speeds do not work or are slower than expected
- The motor turns freely by hand but will not spin.
The capacitors are housed in a black box inside the switch housing of the fan. If you experience any of the above issues, your first step should be to check the capacitor box to see if all the capacitors are okay. In case it appears melted or burnt, there are high chances one or all of your capacitors are damaged.
If only one of your capacitors is damaged, you will still be required to change the entire capacitor box. However, if there are other issues apart from the capacitors themselves, you may want to try and repair them first before deciding to replace the entire capacitor box.
How to Replace a Ceiling Fan Capacitor
If you choose to replace individual capacitors, make sure you have the necessary tools and skills to work with electricity. Of course, it is a must to always switch off the power before you start working on the capacitors. Also, make sure you have a voltage tester to check and see if there is currently flowing through the capacitors before you start working.
Place a step ladder beneath your fan, making sure that it is high enough to reach the fan without stretching yourself too much. Although replacing the capacitor can be straightforward, you will have to know the value of the capacitor in question. In most cases, you can determine the value of each capacitor by looking at the margins in the case of the capacitors.
If the readings are worn out, you may want to consult the original manufacturer. Once you have the values, you should also determine if your capacitor uses two wires or three-wire. With two-wire capacitors, the work is much easier since they only have one capacitor value.
All capacitors are valued with the value measured in “microfarads” (uf). For fans that have more than one speed, there is usually more than one capacitor within the box. In some instances, one capacitor with two or more values may be used to save space. For instance, a three-wire capacitor may contain 2uf and 4uf capacitors in one case with one common wire.
In such a situation, you will find that one wire goes to 2uf and the other to the 4uf side. This is almost always the case with a three-wire capacitor fan. In such a case, you will realize that the color of the wires is different from the original capacitors. In such a case, you must be careful to determine which wire is connected to which value. Some manufacturers have this information on their packaging.
When replacing the capacitor for a ceiling fan, there are various factors to consider. Among the factors that count include the capacitor value and the nature of the ceiling design. In all these factors, it is your duty to make sure you have the right capacitors and connect them rightly so as to enjoy a fully functional fan.