[jacelam]

I want to install a programmable wall switch for my front porch light but the new switch has 4 wires and I have parallel wiring with only 2 wires. I don't know what to do with the white neutral and the green ground. Help.

[stanfortyman]

Why not start by telling us the manufacturer and model of the switch.
Also, exactly what wires are in the wall box?

[jacelam]

It is a Westek model TMDW10. See this example.- http://www.amazon.com/Westek-TMDW10-Hardwire-Indoor-Digital/dp/B002YGS6RC The switch will be indoors and control an outdoor porch light. Thanks.

[jacelam]

I forgot to tell you what's in the box. This switch in a box with two other switches that go to the upper and lower hallways. Those switches each have a second switch in the upper hallway. The wires in the box are configured this way: one wire comes in from the left to the first switch and connects to the lower terminal. Then a small wire connects that wire to the lower terminal on the next switch beside it. A wire from that switch connects to the lower terminal on the switch I want to replace.

The upper terminal of each switch is connect to a separate wire that comes into the box. Those must go to the lights that they control. Hope this helps.

[hkstroud]

There should be a lot of bare wires and a lot of white wires in the box. Remove old switch. Connect the green wire to the bare wires, connect the white wire to the white wires.
Connect the black wire of the programmable switch to the black wire coming from the adjacent switch. Connect the red to the black wire going to the light.

If I have misunderstood and there are no white wires in the box, that means you have no neutral in the box and you can't use this switch.

[jacelam]

hkstroud --I don't know if you misunderstood or not -- I don't know what you mean by bare wires. My house was built in 1923 and has thick black fabric covered wires. They are all the same -- black. And there are not a lot of wires. It is as I described them in an earlier message, the switches are connected on the bottom terminal -- switch to switch. Each switch has a wire that is connected to its top terminal that disappears out the back of the box to its light/load. There are no white wires and there is no ground.

Is there another type of a timer I would use? A photoelectric cell doesn't work because it is always dark under the porch roof. It never turns off.

Thanks.

[hkstroud]

Ground wires are bare (uninsulated or green). Neutral wires are white, although not all white wires are neutral, hot wires are some color other than green or white, usually black.

You would not have any ground wires (bare or green) because your house predates the requirement for ground wire installation.

Therefore, you will only have two wires, hot and neutral. Switches interrupt the flow of current. The hot is always wired to the switch.

There are a couple different way a light fixture can be wired. One is to run the hot and the neutral to the switch box. You connect the incoming hot to one terminal of the switch and the outgoing hot to the other. The neutral coming into the box is connected to the neutral going out of the box to the light.

Another way is to run both the hot and the neutral to the light fixture. The neutral is connect to the light. The incoming hot is connect to a cable that goes to the switch box. The current goes to the switch on one wire of that cable, goes through the switch, and comes back to the light on the other.

When lights are wired the second way there is no neutral in the switch box. You need a neutral to make the programmable switch work. The white wire of the programmable switch is the neutral.

Given the age of your wiring you probably can't tell the color of wires. Are there other wires in the switch box that are just connect together and not connected to the switch.