Trying to hook up intermatic timer ei500 with only black @white wire

Copy following link for T103 timer wiring options:
The clock motor is 120Volts, but clock motor can be changed from WH1570 to WG1573, and this action changes 120V T103 into 208-277V T104 timer:
http://waterheatertimer.org/How-to-wire-T104-Intermatic-timer.html#T103

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Timer is not identified. Battery-operate timers wire differently than timers that require neutral wire.
http://waterheatertimer.org/Intermatic-timers-and-manuals.html

For 4-wire battery-operated Intermatic EJ500, ST01C, and Ei600, Ei400 wiring:
http://waterheatertimer.org/ST01C-program.html#ST01C

For 4-wire Intermatic Ei200 series, KM-series, Ei500 that require neutral wire
http://waterheatertimer.org/Programmable.html#wire

Add a comment with model number for more specific information

Sounds like this was probably a three-way switch you are replacing as there is no neutral (white) wire in the box. If so, you can splice the white wire to the green wire in other three-way switch box; then hook the green wire in the box you are placing the timer to the white wire of the Utilitech timer.

If your box contains 2 and only 2 wires, then the Utilitec timer will not work.
You need the Intermatic ST01C or EJ500 timers that operate with a battery.

I have tested the Intermatic and Utilitec timers:
http://waterheatertimer.org/Program-wire-Utilitec-0141224.html
http://waterheatertimer.org/ST01C-program.html#wire
Do not connect white and red wires together on any timer, but thank you for solving the problem why lights blink when connecting timers.

Now lets look at your wires.
Scrape paint off the wires so you can identify white and black.
According to your information, the black wire inside box will connect to timer-black wire.
The red wire always goes to Load (your light, fan, motor)
The white wire is necessary to complete a circuit so the clock inside timer will operate.
The timer has a clock just like your alarm clock, and it needs to connect back to neutral busbar in breaker box.
This is why the battery-operated timers will work with two wires, the clock runs on battery.
The Utilitec timer-white wire is the wire that goes to Neutral
The timer-white wire is supposed to connect to the other white wires that are twisted together and covered with a wire nut ... but some boxes do not have this neutral wire
To work-around, the timer-white wire can also connect to a bare ground wire.
The bare ground wire also connects to Neutral busbar in breaker box

If you do not have a neutral or ground wire as described above, then you need the battery-powered ST01C or EJ500 Intermatic timers.
See if you can pull some more of the wire into your box ... there might be a ground wire that was cut off and pulling more wire might reveal a ground wire. This will salvage the project.
Aplus is one of many places that sell the Intermatic timer
http://www.aplussupply.com/intermatic/timer.htm

For more about electric wiring:
http://waterheatertimer.org/See-inside-main-breaker-box.html
http://waterheatertimer.org/B220C.html

You posted under ST01C timer which has 3 wires: black blue and red (no white wire)
Your description seems to say your timer has 3 wires: black white and red

These are two different timers
I'm going to give you two different instructions that are dead-accurate for both types of timers above:

1) Instructions for ST01C and EJ500 Intermatic timers with black blue and red
Lets do the black and white with electricity:
The black Hot wire connects to Timer-black-wire
The white Neutral wire connects to white wire going to Load (to lights)

Now the black and white to the Load (lights)
The black to Load (to light) connects to Timer-blue-wire
The white wires are connected together with wire nut

The red wire is capped off, and used only if you have 3-way switching.
Green connects to bare ground

2) Instructions for all in-wall timers with black, red and white wires (except Aube series timers)
Lets do the black and white from electricity
The black Hot wire connects to Timer-black-wire
The white Neutral connects to Timer-white-wire and to white wire going to Load

Now the black and white to the Load
The black wire to Load connects to Timer-red-wire
all three white wires are connected and covered with wire nut
Green connects to bare ground

DO NOT CONNECT RED TO WHITE with any model in-wall timer and then turn on power or it can blow out the timer >>> I just did that while experimenting with the Utilitec 0192773.
Red wire goes to Load on all timers, except with Intermatic ST01C and EJ500

EJ341 has 2 wires

Here is link to product manual at Intermatic. Manual shows troubleshooting, but doesn't show "SOU"
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ST01C works on a 3-way circuit > If another switch is involved, or if switch or timer are not grounded properly, it might affect timer. Troubleshoot says disconnect red wire from 3-way circuit, and see if problem continues, and then suggests replacing timer.

Manual says if CR2 batteries are weak, then BATT shows on screen. Also says weak batteries will cause circuit not to work.
Check the CR2 batteries: Timer holds programming while you replace batteries and clean terminals.

ST01C programmable timer works on circuits up to 100 feet >> I assume because it's battery operated >> electrical interference affects the circuit because troubleshoot lists 'buried wire' as cause of failure. I guess nearby electrical devices could affect performance of timer.

Timer is rated for 15 amps which means practical maximum of 12 amps >>> so 120 volts x 12 A = 1440 watts max or 14-100 watt bulbs >> if you are running more watts, or running close to maximum, or if timer gets warm during operation, this would shorten lifespan simply by heat affecting the circuit.

Interesting that the EI600, EJ500 & ST01C battery-operated timers each has troubleshoot section in manual >>> implying these timers are problematic. ST01C has limited 1 year warranty. EI600 has limited 5 year warranty.

ST01C has 40 on-off programs per week.

If 7 on-off events per week can do the job, you can switch to the EI500 [click on EI500 to access manual]
http://www.intermatic.com/products/timers/in-wall%20timers/digital%207-day%20time%20switches.aspx
>>> the manual shows no troubleshooting section. The EI500 requires connection to neutral or white wire, since the timer runs on electricity instead of battery

[you can use ground wire instead of neutral]
http://waterheatertimer.org/Wiretimer.html

You can compare different types of programmable wall timers:
http://waterheatertimer.org/Programmable.html

Generally your hook up is like this.
G - Ground - Green or bare wire
B - Hot - Black wire
W - Neutral - White wire
R - Switched - Hot when on
On your three wire
G - Ground - Green or bare wire
B - Hot - Black wire - hook to switch wire from switch
W - Neutral - White wire

you should also check: http://www.intermatic.com

The wires on your new switch are intended for black = power .. white = neutral . and red = lights .. with two black wires on the old switch I am assuming that there is a bundle of white wires in that wall box, the white timer needs to join that bundle ... then you need to determine which black wire is the power from the electrical panel ( voltage tester) and connect to the black timer wire .. the red timer wire connects to the other black wire in the wall..

Please Vote !!

That is a three way timer. There is no wire that the white wire gets hooked to. The black is the hot, the blue sends power to the device, and the red goes to a switch that connects it to the blue wire essentially. Here is a PDF of the directions, including wiring diagrams.

http://www.intermatic.com/~/media/files/intermatic/products/instructions/timers/ei600c%20-%20english.ashx