Last Updated on October 9, 2022 by Barry Gray
There are many ways ceiling fans can be controlled, including pull chains, wall controls, remote controllers, and light switches. When a ceiling fan is wired to a light switch, the switch can be used to power the fan on and off. However, many homeowners have wondered whether dimmer switches can be used to power fans and control speed settings.
While regular light switches can be used to power ceiling fans, dimmer switches are not compatible with them. Dimmer switches adjust brightness by regulating voltage, while fan speeds rely on amperage being regulated. Due to this, dimmer switches are not compatible with ceiling fans.
If you want to understand why dimmer switches cannot be used to control ceiling fans, we’ll explain everything you want to know. We’ll even break down what could happen when homeowners attempt to wire ceiling fans to dimmer switches!
Can Ceiling Fans Use Dimmer Switches?
Ceiling fans will generally have at least three overall speed settings. Of course, this allows users to adjust the fan to their preferred speed. Some fans may have more speed settings than others. However, fans also vary in how they are controlled, of which there are four overall methods.
Firstly, ceiling fans can be controlled with wall controls that allow you to turn the fan on or off and adjust speed settings. Remote controls are another way ceiling fans can be controlled and function in a similar way to wall controls.
Many ceiling fans with the standard three-speed settings have a pull chain that can be used to power the fan and cycle through the different speed settings. Finally, ceiling fans can be controlled via a light switch. When ceiling fans are wired to a light switch, you can easily turn them on using this conveniently located switch.
Due to this, many homeowners have wondered whether dimmer switches can be used with ceiling fans. Of course, dimmer switches are another type of light switch which allows homeowners to adjust the brightness of a light. Many homeowners hope that dimmer switches can be used to power fans and control their speeds.
Unfortunately, dimmer switches cannot be used to control ceiling fans. If you attempt to wire a ceiling fan to a dimmer switch, you’re likely to run into various issues. In the following section, we’ll explain why dimmer switches cannot be used with ceiling fans!
Why Can’t Dimmer Switches Control Ceiling Fans?
In order to understand why dimmer switches cannot be used to control ceiling fans, we need to explain how both dimmer switches and ceiling fans function. Of course, this will reveal why these devices are not compatible with one another. Firstly, let’s take a brief look at dimmer switches!
Typically, dimmers control the flow of electricity through the circuit of a light fixture, switching it on and off as needed. As a result, electricity is diverted away from the light bulb. This reduces the current flowing through the bulb, allowing you to adjust the level of light.
The less voltage there is, the dimmer the light will be. As voltage is increased with the dimmer switch, the light will become brighter. Overall, this means dimmer switches work by regulating the voltage in the light’s circuit. Now that we’ve looked at how dimmer switches function, let’s consider the functionality of ceiling fans.
Ceiling fans are powered by single-phase induction motors. Induction motors like this rely on the phase relationship that exists between voltage and current. To switch between variable fan speeds, the amperage in the fan’s circuit needs to be regulated.
From these descriptions, it’s clear that there’s a key difference between how dimmer switches and fan controls differ. As we explained, dimmer switches work by regulating voltage, while ceiling fan speeds require amperage to be regulated. Due to this distinction, dimmer switches are not compatible with ceiling fans.
Ultimately, a dimmer switch will not be able to regulate the amperage in the ceiling fan that’s needed to change speeds. Instead, it would attempt to regulate the voltage, which will hinder the phase relationship needed for induction motors.
What Happens When Dimmer Switches Are Connected To Ceiling Fans?
Dimmer switches are intended for use with light fixtures. In fact, this will be clearly stated on the packaging of many dimmer switches today. As we explained, dimmer switches cannot be used to control ceiling fans. However, many homeowners have been curious regarding what would happen if a dimmer switch was connected to a ceiling fan.
Firstly, connecting a dimmer switch to the fan will damage the fan’s motor. When the dimmer is set to a higher setting, the fan motor will not be able to function with the excess voltage flowing through the circuit. As we discussed, ceiling fans are induction motors that rely on the phase relationship between current and voltage.
This excess voltage will cause the motor to burn out. However, it can also result in contact within the ceiling fan melting. Of course, these issues result in too much voltage when the dimmer switch is set to a high setting. Now, you might be wondering about the low settings.
Unfortunately, the restricted voltage will not be able to slow your ceiling fan down. In fact, a connected dimmer switch set to a low setting might not have enough voltage to start the fan at its base speed setting. In turn, this highlights why fan speeds need their amperage regulated and not their voltage.
Ultimately, connecting a dimmer switch to a ceiling fan can pose a safety threat due to these factors. By changing the voltage running through the fan’s circuit, the fan is likely to overheat. In many cases, this can be a fire hazard.
Even though ceiling fans can be powered by regular light switches, dimmer switches do not work with them. The brightness of a dimmable switch can be controlled by regulating the voltage, while the speed of a fan is controlled by regulating the amperage. As a result, ceiling fans cannot be controlled with dimmer switches.