I want to replace a standard wall switch with a GE 15086 Digital Timer. The box has only a black, white and copper wire. It does not have BOTH a pair of wires from the source AND a pair of wires to the load. Can I install the 15086 here? If so, how should it be wired? If not, please recommend an alternate automatic timer. Thanks, Ed

I test timers, and no damage is done.
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

Sounds like you wired red and white wires together, or installed timer in place of 3-way switch.
15086 will not replace a 3-way switch.
For example, when 2 switches control hallway light, that is 3-way.
Link above has list of timers that replace 3-way switch.

How to wire 15071, 15086, 15265, 15266 timers:
1) Switch has 2 insulated wires. Take switch wires and connect them to timer-black-wire and timer-red-wire. Choose either one for now.
2) In back of electric box are white wires twisted together and covered with wire nut. Connect timer-white to these wires. This will power timer electronics.
3) If electric box does not have white wires described above, then connect timer-white to bare ground, along with timer-green wire.
4) Turn on electricity, and push ON-OFF button located in each corner. If lights come on, timer is wired correctly. If lights do not come on, then reverse timer-red and timer-black wires.

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GE 15086 programmable timer replaces single-pole switch only.
Single pole means 1 device turns Load on-off.
3-way is where 2 devices turn Load on-off, for example 2 switches located in hallway.

Your existing timer has white, black and blue wires.
Your new timer has white, black, red and green wires.
Green wire connects to bare ground wire in every occasion with every wiring device.

Electricians don't guess, they test the other wires.

Remove old timer.
Separate wires for testing.
Turn on power.
Tape ordinary tester leads to wood sticks to keep hands away from power.
Test each wire to bare ground wire.
Tester will light up on Hot wire. The Hot wire will connect to timer black wire.
Now test Hot wire to each other wire (except bare ground)
Tester will light up on Neutral wire. Neutral wire connects to timer white wire.

The remaining wire connects to timer red wire.
After connecting timer, push manual override button to check that Load turns on-off.

Manual override on 15086 is the door that covers buttons > use door as push button to check Load.
Next, program the timer.
Programming is straightforward and similar to other timers.
If you have a problem, add a comment.

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Your timer is bad. It comes with 1 year limited warranty.
Buy one at Home Depot and then return defective one.
Make note of wiring before removing bad timer, so re-wire is easy.

GE 15086 is White 7-day digital, non-astronomic timer made by Tork, and sold on-line and at Home Depot.
On the shelf, 15086 timer looks identical to 15071 >> same package >>> difference is 15071 offers daylight savings time and random option, and costs a bit more.

These in-wall timers usually last a few years, and some can last for several years.
Especially when timer operates from electric circuit and not battery.
15086 operates from electric circuit.

15086 manual on-line:
http://waterheatertimer.org/pdf/GE-15086-Manual.pdf

Woods timers:
http://waterheatertimer.org/Woods-timers-and-manuals.html
Scroll down page to make sure your timer is shown.
You posted under Woods 59018-59028

GE 15086 timer has OFF-Timer switch
http://waterheatertimer.org/images/GE-15086-programmable.jpg
http://waterheatertimer.org/Programmable.html#Aube
Add a comment to identify timer, and I can help more

Double-check wiring:
1) Timer-green-wire connects to bare ground wire.
2) Switch has 2 wires. Take switch wires and connect them to timer-black-wire and timer-red-wire. Choose either one for now.
3) In back of electric box are white wires twisted together and covered with wire nut. Connect timer-white to these wires.
4) If electric box does not have white wires described above, then connect timer-white to bare ground.
5) Turn on electricity, and push ON-OFF button. If lights come on, timer is wired correctly. If lights do not come on, then reverse timer-red and timer-black wires.

I've tested these timers.
Here's what to do:
1) Connect green to bare copper
2) Switch has 2 wires. For now, connect these two wires to timer-black and timer-red. Choose either one.
3) In back of wall box are white neutral wires twisted together and covered with wire nut. Timer-white wire connects to these white neutral wires. This action gives power to time clock.
4) If wall box does not have white neutrals described above, then connect timer-white to bare ground wire. Bare ground connects to neutral busbar in breaker box.
5) Turn on power and click manual override button or switch. If lights turn on, timer is wired correctly. If lights do not turn on, then reverse timer-red and timer-black wires.

http://www.manualsdir.com/manuals/400481/ge-in-wall-15086-ge-smart-digital-timer.html

GE 15086 is a 7-day programmable timer. It has more wires than spring-wound timer because clock motor runs on 120V circuit, just like ordinary electric clock. The clock on spring wound timer operated by a spring.



If I understand correctly, the old timer has 2 wires. One of these wires is the Hot wire ... and that wire will connect to GE timer black wire.
The other wire from old timer goes to Load ... and that wire will go to GE timer red wire.

Instructions on a lot of these timers say, it timer doesn't work, then reverse the two wires described above ... this is because timer only works when Timer black connects to Hot.

You can also turn on power and test each wire that came off old switch to bare ground wire. When tester lights up, that is Hot wire.

GE timer Green wire connects to bare ground wire.

Moving on to GE timer white wire. This wire is necessary for the clock to run. This wire connects to Neutral wire which is usually white. You can test for Neutral by testing Hot wire to each white wire in box ... when tester comes on, that is Neutral.

If you do not have a white Neutral wire, then connect GE timer white wire to bare ground wire. This is not code, but it will work fine until you hire electrician to run Neutral into box.

EJ341 has 2 wires

Review:
Black goes to Hot wire from breaker box
Red wire goes to Load (light, fan, motor)
White wire goes to Neutral
Green to bare copper ground wire

Orientation:
Your original switch had 2 wires plus bare ground.
One of these wires is Hot, the other goes to Load.
You said original wires are Red and Black

How do you find Hot wire?
-Your original switch had 2 wires.
-Remove timer from box.
-Pull original 2 wires out where you can test them
-Turn on power
-Use regular tester
-Tape tester leads to wood sticks so your hands stay away from voltage
-Power is on
-Test each original wire to bare ground wire
-When tester lights up, that is Hot wire ... this wire connects to Black wire on timer
- The other wire goes to Load so it connects to Red wire on timer

How to test for Neutral wire
Test Hot wire to your white wires - No need to untwist them.
When tester lights up, that is Neutral
White wire from timer connects to Neutral.
Green goes to ground wire.

How to reset timer
I'm not sure which timer you have. Probably GE 15086. Reset is small round button below HOUR button. Use paper clip and push-in reset until timer flashes 12 o'clock.

GE 15086 can replace single pole switch only.
If you have "3-way" switch, that is when 2 switches control same light, for example in a hallway.

Open link below to identify GE15086 timer, see wiring instructions, on-line manual <> and see list of timers that can be used for 3-way switching with links to those timers and manuals:
http://waterheatertimer.org/GE-timers-and-manuals.html#15086

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