Why Does My Light Switch Get Hot? (Find Out Now!)

If your light switch is hot to the touch, it could be related to a few different reasons. But the biggest thing to note is a hot light switch is a fire waiting to happen. As soon as you notice the temperature is warmer than warm, call a professional right away.

A light switch gets hot if the switch is overloaded. Different switches have different power ratings, and you shouldn’t have more fixtures on the switch than it can handle. When a switch starts to wear out and fail, it will get hot to the touch. Faulty or improperly installed wires spark and generate heat which also causes the switch to get hot.

Before we discuss the reasons a light switch gets hot, let’s talk about switches that are warm to the touch. This is actually perfectly normal, especially for dimmer switches that are turned on.

This warmth comes from an electrical component called the triac. For alternating currents, this component is called the triode. As the current passes through the light fixture, the triac or triode fluctuates the amount of electricity.

You might feel a small amount of warmth if the dimmer is tied to a 100-watt load. The heat becomes more noticeable once the load reaches over 300 watts.

Similar to outlets, light switches have a limited amount of power they can handle. Different switches have different power ratings. If a switch is overloaded, there is a serious risk of fire. It should immediately be replaced with a switch that has the proper amps to support a fixture.

Most residential light switches are rated to carry 15 amps. Industrial switches are usually rated at 20 amps. Your breaker panel will be able to tell you how many amps the light switch can carry.

A further solution to this problem is to replace the faceplate. Plastic tends to hold more heat, while metal dissipates it. Replacing a plastic cover with a metal one may also cut down on the heat you feel.

After much use, a light switch can start to wear out. They should last a very long time, but they do need to be replaced at some point.

When they wear out, the electrical contacts produce small sparks every time the light is turned on or off. The electricity begins to flow more freely over time because the contacts aren’t meeting correctly. As the sparks fly, they heat the switch, making it feel hot.

It should be pretty obvious that freely flying sparks are a major fire hazard.

It doesn’t matter if the wiring was professionally installed. As it ages, wiring can become broken or loose. Light switches also retain heat over long periods of time. This can cause cracks in the wire’s insulation, which can, in turn, cause short circuits, arc faults, or fires.

When a wire loses its integrity, the results are similar to a failing light switch. Any bad connections will spark and generate heat, and you’ll feel it on the light switch itself.

Additionally, bad wiring can block a current’s flow which also produces heat. The best way to fix faulty wiring is to have it replaced by a licensed professional.

We know a warm dimmer switch is normal. But a hot one is not. If you have an older dimmer switch, you may notice it gets hot when you dim the lights. A modern dimmer switch on the other hand may get hot when brightening the light.

This is a result of an overloaded or unevenly balanced current. The switch’s rating is not sufficient enough to carry the wattage of the bulb in the fixture. You can either change out the switch for one with a higher amp rating or use a bulb with a lower wattage.

We’ve discussed a good many reasons why your light switch feels hot and what you can do to fix it. Perhaps you still have more questions. Below are some other things people wondered about the functions of a light switch.

Most likely, this is occurring because the switch is worn out. Above, we talked about how poor connections can cause sparks. These sparks can sometimes appear on the other side of the faceplate where you can see them.

Similarly, if you operate the light switch too slowly, the connectors have a gap just far enough for an arc to occur. Meaning, the electricity literally arcs from one connection to the other in mid-air. This may also cause a visible spark.

The general rule is if you can’t touch the light switch for more than a few seconds, it’s too hot. Some switches are built to withstand temperatures up to 195 degrees Fahrenheit. However, the average dimmer switch is built to withstand temperatures around 140 degrees Fahrenheit.