1. Over lamping:
This is the most common cause of a hot dimmer. Each dimmer has a maximum wattage rating that should not be exceeded. The most common size in a residential electrical wiring system is 600 watts but larger 1000 watt dimmers are available too. To check the wattage rating of your dimmer you will need to remove the finish cover plate and find the rating on the front of the device’s mounting bracket.
To determine the wattage being used, add up the wattage of all the light bulbs being controlled by that dimmer. The closer you get to the maximum recommended wattage the warmer the device will get. If the total light bulb wattage is above the device’s maximum rating you have a case of over-lamping. This should be corrected for safety by either upgrading to a larger wattage device or reducing the total light bulb wattage with smaller bulbs, LED bulbs or CFL’s.
2. Removing The Cooling Tabs
Located on both sides of the device are metal cooling tabs that can be removed for fitting the device into the electrical box. When these tabs are removed, the maximum wattage rating of the device has been reduced. Removing the tabs on just one side will reduce the recommended maximum by 100 watts and removing both sides will reduce it by 200 watts. If your dimmer gets hot and you are not over-lamped check to see if these tabs are still present.
Tip:
Plastic electrical boxes offer little heat dissipation where metal electrical boxes deliver much greater heat dissipation. The metal mounting bracket of the dimmer is the main source for heat to escape; it also has those removable metal cooling tabs. The dimmer’s metal mounting bracket attaches directly to the electrical box, hence when attached to a metal box a greater amount of heat sink transference will occur keeping your dimmers cooler. When possible, replacing your plastic electrical box with a steel box is another option. A larger or deeper box will provide additional heat reduction too. If you are installing a dimmer switch in a new location and a new electrical box needs to be added always choose a metal box over a plastic box for heat sink transference. For more expert electrical tips review our web site or contact our Mesa electricians free of charge.
3. More than one device in the same electrical box
Having more than one dimmer in the same electrical box can increase the temperature significantly too. Remember, these naturally get warm when used so combining more than one in the same electrical box will increase the generated heat. Also keep in mind that fitting two or more dimmers in the same box will require the removal of the metal cooling taps on the sides. This, as you know, will reduce the maximum recommended wattage for each switch. If your dimmers are excessively hot, consider lowering the total light bulb wattage being controlled by that device or upgrading the size of the dimmers.
Tip:
Just like replacing a plastic electrical box with a metal one will reduce heat, replacing a plastic finish cover with a metal one will also reduce heat. The finish cover attaches to the front of the switch’s mounting bracket which is the primary source of heat dissipation so additional metal equals greater heat transference. A larger size metal finish plate can also be used for increased heat reduction.
Dolce Electric Co schedules an in-office electrician in Mesa AZ that you can consult with free of charge about any electrical question. He has many do it yourself tips that can save you the cost of an electrical service call.
4. Failing Switch
A dimmer that is failing will often be making a poor or weak connection inside the device, which can also create additional heat. A small crackling noise can sometimes be heard when a failing dimmer is energized. Other dimmers will no longer provide adjustable light levels and only work on or off when they are failing. If you suspect that your dimmer is failing, now would be a good time to replace it. It won’t fix itself and sooner or later it will fail completely.
As you can see, a warm dimmer is common but an excessively hot dimmer should be corrected. Often times simple adjustment can be made to give you the peace of mind you’re looking for. If you have a concern regarding your dimmers you can consult with our Electricians in Mesa AZ free of charge today, Monday, February 18th, 2019, during office hours.