How to Replace a Light Switch
Purchase a new light switch that meets your requirements at a local home repair or hardware store., Disconnect the power to the light switch at your home’s electrical service panel (also known as the breaker box or load center)., Test the switch...
Step-by-Step Guide
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Step 1: Purchase a new light switch that meets your requirements at a local home repair or hardware store.
Tell the store employee what kind of switch you want and how many you’ll need, and they can help you determine the best purchase.
Single-pole switches are the simplest and most common.
A single-pole switch has just two positions—“on” and “off.” -
Step 2: Disconnect the power to the light switch at your home’s electrical service panel (also known as the breaker box or load center).
It’s a steel box that may be located inside the house, in the basement, in the garage, or along one of the outside walls.
You can either turn off the breaker that controls the lights in the specific room you are working on or turn off all the power to the house by switching off the main breaker. , Flip the light switch on and off several times to be sure the power is off. , Using a flat-head screwdriver, turn the screws holding the plate in place counter-clockwise to loosen them. , Once the switch plate cover has been removed, use a flat-head screwdriver to remove the screws mounting the switch to the wall.
Turn the screws counter-clockwise until they are freed from the wall. , Pull the switch away from the wall to expose the wiring, but leave the wires connected.
Use a circuit or voltage tester to ensure no current is flowing.
If using a circuit tester, hold one probe of the circuit tester against the grounding wire (green or bare copper), and touch the other probe to each of the screw terminals (located along the sides of the switch).
If using a voltage tester, simply hold the tester near the wires.
If the tester registers any current, stop the project immediately until you’re able to power off the circuit. , Pull the switch as far from the electrical box as the wires allow.
Take careful note of how the switch is wired.
The wires will be connected to the switch by either screw terminals or push-in connectors.
Take a picture or draw a diagram so you can wire the new switch in the same way. , Use a marker or colored tape to uniquely label each wire so you can tell them apart.
The box will contain one or two cables (or sets of wires).
If the box contains two cables, it means the switch is in the middle of the circuit.
You’ll see a total of six wires: two black (hot) wires, two green or bare copper (grounding) wires, and two (neutral) wires, which may be black, white, red, or any other color than green.
Mark the wire connected to the brass screw terminal or to the hole on the same side as the brass terminal as the “hot” wire.
Mark the wire connected to the silver screw terminal or to the hole on the same side as the silver terminal as the “neutral” wire.
Finally, mark the green or copper wire connected to the green screw terminal (on the other side of the switch from the brass and silver terminals) as the “grounding” wire.
If the box contains only a single cable (or single set of three wires), it means the switch is at the end of the circuit.
You will see a black (hot) wire, a green or bare copper (grounding) wire, and a third (neutral) wire, which may be black, white, red, or any color other than green.
Mark the wire connected to the brass screw terminal or to the hole on the same side as the brass terminal as the “hot” wire.
Mark the wire connected to the silver screw terminal or to the hole on the same side as the silver terminal as the “neutral” wire.
Finally, mark the green or copper wire connected to the green screw terminal (on the other side of the switch from the brass and silver terminals) as the “grounding” wire. , The switch may have either screw terminal connectors, which will be located along the side of the switch, or push-in connector holes, which will be located at the back of the switch.
If the switch has both screw terminals and push-in holes, most electricians recommend using the screw terminals for a more secure connection.
But do not over-tighten; you may break the internal parts of the switch.
If you tighten the terminals and hear a crack, discard the switch and use another.
If the wires are connected to screw terminals, turn each screw counter-clockwise with a screwdriver to loosen and slide the wire out with a pair of needle-nose pliers.
If the wires are connected to push-in connectors, the holes that the wires are pushed into will typically have a small slot beneath the hole.
Insert a small screwdriver into the slot and push forward to release the wire. , Attach the black wire (hot) to the brass screw terminal.
Either:
Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw and then tighten the screw clockwise to secure the wire.
Or push the wire into the push-in hole on the same side of the switch as the brass screw. , Either:
Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw.
Tighten the screw clockwise to secure the wire.
Or push the wire into the hole on the same side of the switch as the silver screw. , Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw.
Tighten the screw clockwise to secure the wire. , You should see the word “top” written on the switch indicating the side of the switch that should be vertically oriented toward the top. ,, Do not over tighten the switch plate, since it may crack under too much pressure. , Go back to the new switch and flip it on and off several times to ensure it’s in working order. -
Step 3: Test the switch.
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Step 4: Remove the switch plate cover.
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Step 5: Unscrew the switch's mounting screws.
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Step 6: Remove the switch.
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Step 7: Pull out the switch.
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Step 8: Check the wires inside the wall box and identify each wire.
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Step 9: Disconnect the wires from the old switch.
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Step 10: Begin connecting the wires to the new switch.
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Step 11: Attach the white (neutral) wire to the silver screw terminal.
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Step 12: Attach the copper (grounding) wire to the green screw terminal on the opposite side of the switch.
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Step 13: Double-check that the switch is properly oriented.
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Step 14: Carefully push the wires back into the box and then push the switch up against the edge of the box and tighten the mounting screws into place.
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Step 15: Replace the switch plate and tighten the screws into place.
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Step 16: Return to the breaker box and turn the power to the light switch back on.
Detailed Guide
Tell the store employee what kind of switch you want and how many you’ll need, and they can help you determine the best purchase.
Single-pole switches are the simplest and most common.
A single-pole switch has just two positions—“on” and “off.”
It’s a steel box that may be located inside the house, in the basement, in the garage, or along one of the outside walls.
You can either turn off the breaker that controls the lights in the specific room you are working on or turn off all the power to the house by switching off the main breaker. , Flip the light switch on and off several times to be sure the power is off. , Using a flat-head screwdriver, turn the screws holding the plate in place counter-clockwise to loosen them. , Once the switch plate cover has been removed, use a flat-head screwdriver to remove the screws mounting the switch to the wall.
Turn the screws counter-clockwise until they are freed from the wall. , Pull the switch away from the wall to expose the wiring, but leave the wires connected.
Use a circuit or voltage tester to ensure no current is flowing.
If using a circuit tester, hold one probe of the circuit tester against the grounding wire (green or bare copper), and touch the other probe to each of the screw terminals (located along the sides of the switch).
If using a voltage tester, simply hold the tester near the wires.
If the tester registers any current, stop the project immediately until you’re able to power off the circuit. , Pull the switch as far from the electrical box as the wires allow.
Take careful note of how the switch is wired.
The wires will be connected to the switch by either screw terminals or push-in connectors.
Take a picture or draw a diagram so you can wire the new switch in the same way. , Use a marker or colored tape to uniquely label each wire so you can tell them apart.
The box will contain one or two cables (or sets of wires).
If the box contains two cables, it means the switch is in the middle of the circuit.
You’ll see a total of six wires: two black (hot) wires, two green or bare copper (grounding) wires, and two (neutral) wires, which may be black, white, red, or any other color than green.
Mark the wire connected to the brass screw terminal or to the hole on the same side as the brass terminal as the “hot” wire.
Mark the wire connected to the silver screw terminal or to the hole on the same side as the silver terminal as the “neutral” wire.
Finally, mark the green or copper wire connected to the green screw terminal (on the other side of the switch from the brass and silver terminals) as the “grounding” wire.
If the box contains only a single cable (or single set of three wires), it means the switch is at the end of the circuit.
You will see a black (hot) wire, a green or bare copper (grounding) wire, and a third (neutral) wire, which may be black, white, red, or any color other than green.
Mark the wire connected to the brass screw terminal or to the hole on the same side as the brass terminal as the “hot” wire.
Mark the wire connected to the silver screw terminal or to the hole on the same side as the silver terminal as the “neutral” wire.
Finally, mark the green or copper wire connected to the green screw terminal (on the other side of the switch from the brass and silver terminals) as the “grounding” wire. , The switch may have either screw terminal connectors, which will be located along the side of the switch, or push-in connector holes, which will be located at the back of the switch.
If the switch has both screw terminals and push-in holes, most electricians recommend using the screw terminals for a more secure connection.
But do not over-tighten; you may break the internal parts of the switch.
If you tighten the terminals and hear a crack, discard the switch and use another.
If the wires are connected to screw terminals, turn each screw counter-clockwise with a screwdriver to loosen and slide the wire out with a pair of needle-nose pliers.
If the wires are connected to push-in connectors, the holes that the wires are pushed into will typically have a small slot beneath the hole.
Insert a small screwdriver into the slot and push forward to release the wire. , Attach the black wire (hot) to the brass screw terminal.
Either:
Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw and then tighten the screw clockwise to secure the wire.
Or push the wire into the push-in hole on the same side of the switch as the brass screw. , Either:
Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw.
Tighten the screw clockwise to secure the wire.
Or push the wire into the hole on the same side of the switch as the silver screw. , Use needle-nose pliers to wrap a little more than half of the bare wire clockwise around the screw.
Tighten the screw clockwise to secure the wire. , You should see the word “top” written on the switch indicating the side of the switch that should be vertically oriented toward the top. ,, Do not over tighten the switch plate, since it may crack under too much pressure. , Go back to the new switch and flip it on and off several times to ensure it’s in working order.
About the Author
Judith James
Specializes in breaking down complex home improvement topics into simple steps.
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