This variable-speed switch controls the speed of a fan. You can easily test and replace it with instructions from the Fix-It Club.
Troubleshooting electrical things is surprisingly easy. Once you understand the device’s as-designed state you can define the problem and start looking for a solution. For example, a cord either delivers electricity to the device or it doesn’t. An electrical switch is on, off, or, in variable switches, at some value in between. A heating element either heats or it doesn’t. By thinking of electrical devices as components that have specific jobs — pass electricity, stop electricity, produce heat, turn a blade, etc. — you can more easily figure out what’s wrong and what to do about it.
Fortunately, there’s a device that can help you test most electrical things. It’s called a voltmeter, a volt-ohmmeter, a VOM, or a multimeter (because it takes more than one electrical measurement); they’re all the same thing. A multimeter measures the amount of power (voltage) being applied, electricity (current) being used, and how much resistance it needs to overcome to do the job. Power is measured in volts (V), current is counted in amperes or amps (A), and resistance is calculated in ohms (Ω).
There’s one more electrical term you’ve probably heard. Defining it will come in handy as you fix electrical devices. A watt is the amount of power consumed by an electrical device when it is running. A 750-watt toaster, for example, uses 750W (watts) of power when toasting your wheat, rye, sourdough, or other bread in the morning.
If you don’t know the wattage rating of an electrical appliance but you do know the amperage (current), multiply it by the voltage. The formula is: V x A = W. Since all plug-in appliances in your home are either 240V (electric stove or clothes dryer) or 120V (everything else) it’s easy to figure wattage. A toaster that is rated at 7.75A (indicated by a label or plate on the toaster’s bottom) uses 930W of electrical power (120 x 7.75 = 930).
Why is this all so important to troubleshooting electrical things? By checking the as-designed state against the actual state you can determine whether something is working properly–and have the first clue toward fixing it. For example, if a switch is supposed to be on (little or no resistance to the flow of electrical current), but in checking the switch you find the resistance to be infinite (no electricity is passing through it), it’s easy to decide that the switch is faulty. Remember: Know what it’s supposed to do, then figure out what it’s actually doing to decide whether it’s working as designed. It’s a simple rule that makes troubleshooting any electrical device easy.
Electrical contact cleaner is useful for cleaning components in small and large appliances, following the manufacturer’s recommendations.
In many cases, electrical appliances and electronic gadgets need only a good cleaning to bring them back to life. Contact cleaners and canned air are the most effective and the most popular products for cleaning electronics. Contact cleaners are special cleaners that dry on contact, and they are used for “fixing” numerous electrical devices. Canned (compressed) air is a useful cleaner for blowing off dust particles from electronics. Don’t use high-pressure air from an air compressor on delicate parts.
Here’s something else you should know about electrical devices: There are only a few types, making troubleshooting relatively easy. Small appliances, for example, either heat something, move something, or both. A toaster heats something (bread). A fan moves something (a blade). A hair dryer does both (heats and moves air). A refrigerator uses a motor to move coolant. Even computers and other sophisticated electrical devices have relatively simple functions. They pass, store, or display data.