As an electrician, one of my most common jobs is repairing or replacing a ceiling fan switch. These 3 or 4 position rotary switches can wear out over time, especially switches that are over 20 years old.
I often find that only one or two of the fan speed control settings work. All that has happened is that the fan controller has failed at a certain position. Every now and then I find that one of the controller wires has fallen out and just needs to be put back in place. This is a common fault due to constant vibrations from the rotary speed controller.
There are now many different combinations of fan controllers available. Some have light switches attached to them, so there might be a few extra wires on the back of the switch. In this post, we'll identify what each wire is, how to install a new ceiling fan speed controller, and theNecessary tools as an electrician.
Note: Electricity is dangerous, so installations and repairs should only be done by a licensed electrician. These tips, tricks and instructions are for informational purposes only.
table of contents
- Ceiling fan does not spin fast.
- How to Replace a Ceiling Fan Speed Control Switch
- How to test 110/240v power
- How to install ceiling fan speed control wall switch
- 3-speed ceiling fan switch wiring diagram
- Energize the Circuit.
- Problems solution
Ceiling fan does not spin fast.
There could be a number of possible reasons why your bedroom ceiling fan isn't spinning, so let's look at some common causes.
- tripped circuit breaker
- faulty wall switch
- The ceiling fan motor burned out.
- Electrical wires are disconnected at wall switch or ceiling fan terminal block.
- Ceiling fan switch is off.
- Remote control batteries are low.
Most of them are easy to fix except for a blown ceiling fan motor where it is better and cheaper to replace the entire fan.
How to Replace a Ceiling Fan Speed Control Switch
First, we need to isolate the fan power. Ceiling fans are often powered by the lighting circuit, so go to the switchboard and turn off that circuit.
Label the breaker with a do-not-operate tag or place electrical tape over the disconnected breaker. If you have fuses, remove the fan power fuse.
Now we need to test if the fan circuit is dead. If the fan was working before, check that it is not working. Try turning on the fan and performing some speed control settings. Always confirm with a multimeter.
Take a screwdriver and remove the outer cover of the fan speed controller, if present. A battery drill orcordless screwdriverwill do this job fast and fast.
Once the wires are exposed, get a multimeter and test that the circuit has been isolated. Never work on live wires. Often fan controllers and light switches have only switch wires and no neutral or ground wires. This will make it difficult to check voltages.
How to test 110/240v power
A quick way to test fan controller power is to turn on the multimeter and set it to read AC voltage. Now place your multimeter between the In point and the Out point. With an open connection you should read a voltage difference.
With the fan controller turned off, we basically have an open circuit so we can measure voltage across this switch. Without the isolated circuit, we would read 110v in the US or 240v in Australia.
If you have access to ground or neutral wires, you can use your multimeter to test for active ground. Non-contact voltage testers are a great way to quickly check an isolated circuit.
Since we isolated the power circuit, we should see 0v AC. Now we can be sure to work on our isolated fan controller. You can read the following post if you want more information aboutWhat is the voltage across an open switch?
How to install ceiling fan speed control wall switch
I always like to override the same switch settings. Basically, there are two different types of fan controllers. Solid state that controls frequency (allowing only part of the current cycle to flow) and fixed speed that varies the voltage to the fan through the resistor.
There are also some variations like light change and dimmer control. So if your fan wall controller has a light switch as part of the setup, get the same type. Many ceiling fans have a built-in light. Some have a lanyard and some have a wall switch.
Many fan speed controllers use sliders to control lighting speed and dimming levels. The Westinghouse 7787300 shown below is a 4 position fan controller so you have more speed control. Convert any 3-speed ceiling fan into a 4-speed fan.
In this case, we will be installing a Deka ceiling fan speed control wall switch with an included light switch. There are now 3 wires in the wall cavity. The purpose of these cables is as follows.
- The red dual core wire supplies power to the wall switch. This supplies power to the fan and light switch.
- A single red core wire is spun to turn on the light.
- The double white wire is the speed control power for the fan.
The image above shows where the fault is. You can only encounter this problem by removing the fan speed controller from the wall. One of the red speed control wires came loose. Since the customer already wants a new fan controller, we will replace it anyway.
Now, depending on how old your home is, your wires may have different colors and wires. They can all be single core or they can all be dual core. As long as you replace the same wires with the same terminals, everything will be fine.
The new fan controller part should already be plugged into the back of the switch. There will be a terminal block that should be marked power and fan input. Be sure to read the instructions that came with the fan controller to identify these terminals.
We will use the switch to turn on the room light or fan light.
3-speed ceiling fan switch wiring diagram
Below is the wiring diagram for a basic 300 watt variable speed fan controller. As you can see there are only 2 wires going to the fan control unit. There is a live input wire and a live output switch for the fan.
If you have more features like lighting and dimmer switches, you will have more wires running through the wall.
I like to remove one strand at a time for a direct replacement. That way you won't be confused about which wire goes where.
After hooking up the 3-speed ceiling fan and light switch, it's time to screw everything back into place. I like to use the new screws that usually come with the new speed controller board.
A quick note is that some people like to usesmart chandelierson your fan lighting. In this way, they can turn on or off the light of a telephone or asmart motion sensorIf that's the case, it's fine to connect the light to an always-on position.
You might have a hard time pushing the big fan controller, so be prepared to cut through sheetrock. Manufacturers sometimes tie the terminal strip to the side of the fan control circuit and this makes it too thick to fit. I just cut the clamp off and attached it somewhere else.
Take your screwdriver and screw the fan control board into place. Make sure it's square and level. If there is a cover plate, reinstall it and place the selector knob on the fan controller.
Energize the Circuit.
Once you are satisfied with the ceiling fan switch wiring, you can remove the breaker latch and power up the circuit.
Be sure to test your new fan speed controller. Perform all settings and also test the light switch if it has one. If all is well, give yourself a pat on the back. If there is a fault, one of the wires may be reversed. You will need to isolate the power circuit again and test what went wrong.
The fan motors may fail, but they will either work or not. 99% of the time it is the fan controller that has failed, not the fan motor. I often find that people want a new ceiling fan because it has noisy bearings.
If after replacing the speed controller, your fan is still not spinning. check the following
- Power or live cable is terminated correctly.
- The output cable is not mixed with another cable.
- Copper wire is properly terminated and not bent over insulation.
- Turned on the breaker or changed the fuse.
- Ceiling fan is not in the off position.
- You have selected the correct season for the year. For example: winter or summer mode. The fan will run in the opposite direction for different seasons.
Now go ahead and upgrade your wall outlets to quad outlets for more power.
Replacing a ceiling fan switch is a simple process that shouldn't take more than half an hour. They look complicated because there are usually 3 extra wires for the speed controller. These should already be connected in their correct position,
It's a good idea to take a photo of the old circuit for reference. Always remember to isolate your circuit and test it with a multimeter.Non-contact power test pensare really useful items for your toolbox. Every handyman and electrician should have one.
If you have any questions, please let me know in the comments below.
I've been a qualified industrial electrician for 20 years and love sharing my home repair knowledge.
I love fast toys like motorcycles, cars, jet skis and boats, so it's easy to write about them.
To keep costs down, I do all my own modifications, repairs and maintenance. These skills I want to share with everyone. DIY is a skill that everyone can learn.