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How to Install an In-Wall Timer

Installing an in-wall timer helps save money on your electric bill because you can program a light switch timer to turn your lights off when they are not needed.  An in-wall timer can turn a regular light switch into a fully programmable lighting system. The great news is, a timer switch is just as easy to install as a regular light switch. Read below where we have given you tips to installing in-wall timer switches.

Installing a programmable in-wall light timer

Preparing the wires. Using wire snips, cut off the ends of the wires you just released. Wire cutters also double as wire strippers, they have different sized holes for stripping various sized wiring. Find the appropriate sized hole for each wire, and strip the rubber insulation about 3/4-inch from the ends you just cut. Cutting and stripping the wires gives you new wire to connect to the new light switch timer.

The new timer switch has wiring that comes from the back of it. This wiring is meant to be attached to the existing in-wall wiring inside your switch box. Follow these instructions carefully.

Attaching the ground wire. Find the ground wire on the back of the timer switch, and attach it to the ground wire inside your switch box. Some wall timers have a ground screw instead; in this case, attach the in-wall ground wire to the wall timer ground screw. Then, tighten it snugly without overtightening. Overtightening may strip your screw.

Connecting the bundled wires. Find each colored wire and connect it to the same colored wiring found on the wall timer. You can secure them with a wire connector; make sure the wire connector is fastened tightly. Before putting the wires back into the switch box, make sure to wrap them with electrical tape, for added safety.

Securing the line in wires. The black line in wires on the wall timer can be connected to the black line in wires you detached from the bottom screw inside the switch box.

Fitting the wires in the switch box.  Place the wires back into the switch box snugly, so that the light cover can be placed on without obstruction.

Installing the wall timer cover. Screw the wall timer cover plate onto the switch box.

Turning the power on. If you are using a manual wall switch timer, you can program it to desired settings before you turn on the power. Digital timers require electric to run the timer panel. You can now turn the power on and test your new wall switch timer.

Gathering needed tools

As with any do-it-yourself project, you will want to be prepared with the right tools to tackle the job. Below there is a list to help you get started.

Project requirements

  • Programmable timer switch and switch plate
  • Voltage tester
  • Phillips, and common head screwdrivers
  • Wire strippers/ wire cutters
  • Connectors
  • Electrical tape

Discovering the benefits of programmable switches

Devices. Programmable switches not only work the lights, but they can also control any electrical device that runs through your wall switch. This includes ceiling fans, televisions, and other entertainment devices, as well as any lamps or table lights you may have.

Programmability. Many in-wall switch models can be preset a full seven days.  You can set the timer to go off an individual, or different times every day of the week. If you happen to be up later than usual and need more light; you can simply touch a button, to keep the lights on.

Size. Programmable light switches are made to fit right in regular light switch spaces. The come with their covers but will fit behind the standard light switch cover.

What happens if there is an electric failure? Light switch timer comes with a backup battery system. That helps to keep the times you have programmed.

Choosing a wall switch timer

There are options you can choose from when it comes to timer switches. So, be mindful when you are picking out programmable light switches for your home.

Two-wire timers. The two-wire timer switch runs on batteries exclusively. Therefore you could be replacing batteries often. However, there is one type of two wire timer switch that does not use batteries. It is called the Intermatic EJ351. The problem you may find with this model is, it is only made to work for incandescent lighting, and won’t work florescent. The EJ251 is simple to install, and many people who are skittish about electrical wiring, may find the EJ251, and other two wire timers less intimidating. To install these, you simply disconnect the two main wires that were attached to the light switch and attach them to the automatic light switch.

Three or four wire in-wall timers. These programmable times require a neutral wire, so they can run on the in-wall electrical wiring, to not run on battery alone. They also tend to cost less, than the two wire timers and seem to be more reliable.

Wiring in your home. Look in your light switch box to see what type of wiring you have. The AC wires can be red, blue, and black wires all clamped together. These wires are considered the (hot wires), and often one of them is ground and neutral wire.

The wire that powers the lights is called a load wire. It is often black and ran alone from a different pole than the bail of wires clamped together.

The neutral wire is white, and the ground wire can be bare wire, green, or copper colored. Both wires may be found in the AC wire bundle.

Manual and digital in-wall timers. Many people may find the manual timer easier to program, and more reliable. Digital timers require a systematic code to be manually typed in, on the tiny button. On the manual timer, you simply turn the timer dial to the desired setting and the lights will go on at off at your preference.

Removing your manual light switch and cover

Anytime you are working with electric, think safety first. Go to the breaker box, find the circuit breaker that feeds power to the wall switch you plan to replace, and shut it off. If you are unsure which circuit breaker it is, flip each one down until the lights in that room turn off.

Removing the switch cover. Most light covers are secured with two screws. You will need Phillip’s head screwdriver to unscrew them. Once they are unscrewed, the cover can be taken off.

Taking out the switch box. There are two tabs, one at the top of the switch box and one at the bottom. Pull the tabs, to release the box. 

Loosening the terminal screws, and disconnection the wires. Once you have removed the box, you will see terminal screws and wiring. Use an electric current tester to make sure the electric is turned off to the switch, before beginning to loosen these screws. Slightly loosen the screws and disconnect the wires. The top screw is the one that supports the load wires. When you free these wires, bend them upward, so they will not get intertwined with the bottom wires. The bottom screws house the line in wires, bend these wires downward. Unscrew the green ground screw, to release the ground wire from the back of the switch. 

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