GE Push-Button Countdown Timer, 5-15-30 Min/1-2-4 Hour, ON/Off, No Neutral Wire, Ideal for Lights, Fans, Heaters, Wall Plate, Light and Fan Timer Switch, 15318 White

This thing works just perfectly for this old house with no neutral wire. I'm using it to control a bathroom vent fan. Here are some things to know:1) You do need to connect this exactly as the instructions say even when you have two black wires that aren't labeled properly as to which one is hot and which one leads to the load (light, fan, etc.)2) The earth ground is required for operation and not just for safety! if you don't see a green wire, look for a naked copper wire which is probably connected to the wall box. You can attach the green wire either directly to the naked wire or screw the green wire to the wall box if the naked wire is screwed to it.3) if you have two black wires, and don't know which one leads to the load, just try to guess based on where the wires are coming into the box. If you know the path through the walls to the load device then that will help. If you guess wrong, the switch won't work properly. In this case just shut off the circuit break and swap the black wires. After that it should work.4) When you restore power, the switch might start up in the "on" state and your load (fan, light) might be running. Just wait a minute or less and it will shut off as soon as the capacitor in the switch charges up. Then wait a few more minutes and the switch should be working as expected.I think the switch probably uses a design like US Patent US5903139A. This charges a capacitor, not a battery, so should have a decently long lifetime.If you do have a neutral wire in your house (2 phase AC power) like most modern houses, then you're probably better off with a design that makes use of the neutral wire and the 2nd electrical phase to power itself. That will avoid the start up delay.

After wiring up this unit - hot to black, load to red and ground to green - and turning the breaker on, I was scratching my head as it didn't seem to work to turn my bathroom exhaust fan on and off. I undid all the connections, reconnected the old switch and everything worked. So I came back to this timer switch and whatever I did seemed to charge the unit and I saw a couple flashes and I was in business.Obviously I didn't read the supplied paper instructions, which specify that the unit takes a minute to fully charge (assuming the minute is after the breaker is turned on) and lights will flash when charged!Anyway it seems to work for its intended purpose. Each of the timer buttons work. When the power button is short-pressed on it activates the last used timer.Easy to install and takes up no more room than a normal two-rocker switch.I have this switch controlling the fan of a Panasonic exhaust-heater-light-night light - 4 rockers on a 2 gang box. The fan and main light were on one double pole rocker and I gave up the main light control and capped off that load. The bathroom has lights anyway and the night light appears just as bright for backup.

I have been using this for several months on my master bath fan. Works great. Adding now to other fans and a recirculation motor.I've experimentally proven that the wires are tinned copper, by scraping off the tin at one location, exposing the copper. The assertion by another reviewer that the wires are aluminum, and are a fire hazard, is false, probably an assumption from appearance.

The switch mostly performs as advertised. But there are some gotchas that you have to look out for.Fair Warning: I am not an electrician.Installation was not difficult. The switch has black, red and green wires. According to the instructions, the black is for the hot side, the red for the load side (bathroom fan in my instance) and the green for earth ground. I could not tell which of my black wires was the load side, so I made my best guess and continued. Upon flipping the circuit breaker back on, the switch/fan came on. According to the instructions this is normal as it "takes about 1 minute to fully charge (the switch)" after which it turned off. I pushed the 5min timer button and the fan came on as expected. I immediately tried pushing some of the other buttons to get a feel for how they worked whereupon the switch turned off and would not come back on no matter which button I pushed. The instructions state "This happens if you cycle the load to(o) many times in a short period. Wait 1 minute and the timer will be ready for use." I waited 1min, didn't work. I waited 5mins, still didn't work. I waited an hour, still didn't work. Lacking any other ideas, I began to wonder if I'd attached the red wire to the hot side. So I rewired the switch and now it seems to work. Cycling the load several times within a short period doesn't seem to cause malfunction.The switch has a small blue light next to each timer button (5min, 10min... etc). When you push one of the buttons, the blue light next to it flashes on twice... and never again until the time expires. Why can't the blue light next to the chosen timer stay on when the switch is on? There's certainly power flowing through the circuit. According to the instructions, "Timer will blink every 20 seconds to show the last time used". **THIS DOES NOT WORK**. Whether the switch is on or off, the chosen timer does not blink every 20secs.Overall it gets the job done (as long as you wire it correctly, it seems). But I wish the light next to the chosen timer stayed on. There's no way to tell what timer the person before you chose.UPDATE: The instructions also state "If you hold the big button down for 5 seconds it will turn on and stay on until hit again" **THIS DOES NOT WORK**. I've tried holding the button down for 5 secs and more. The switch eventually turns off based upon the last timer chosen no matter how long you hold the button down.