You have electric water heater.
You replaced elements and thermostats but heater still won't work.
And tank was completely full of water, and water was running out of a faucet before turning power ON.
If elements are not fully immersed in water, they will instantly burn out.
If upper element is burned out, then tank will have NO hot water.
If lower element is burned out, and upper element is not burned out, then tank will have some hot water.http://waterheatertimer.org/How-to-test-water-heater-element.htmlhttp://waterheatertimer.org/How-it-works.htmlIf elements did not burn out, then that leaves 1 main suspect: the electricity.
1) Push in ECO red reset button on upper thermostat. If ECO is tripped out, then heater will not work.
2) Click circuit breaker all the way one direction and then back the other direction to make sure breaker is latched.
3) If tank has 2 elements, then it is 240volt.
If 1 leg of 240Volt circuit is not working, then 240V appliance will not work.
240Volt circuit needs both hot wires to complete the circuit:http://waterheatertimer.org/How-to-wire-EH40-hot-water-heater-timer.html#120-240
Buy cheap multimeter from Home Center and set dial to 240-250-277VAC
Tape tester leads to woods sticks to keep hands away from power.
Power is ON
Test across top 2 screws on upper element should show 220-240 volts.
If you have 240 at top two screws, then skip down to step 6.
If no reading across top two screws, then move to top of tank.
4) Open connection point where wire connects to heater.
Test across both insulated wires should get reading of 220-240 volts.
If no reading, move to circuit breaker box.
5) Mark water heater breaker.
Turn off all breakers except water heater breaker and main breaker. (and breaker to light fixture where box is located)
Do not hold or touch or lean against anything metal.
Stand on dry boards and wear dry clothes.
If main breaker is OFF, the big wires that connect to main breaker are still HOT.
Remove box cover.
240Volt breaker has 2 wires connected with screws.
Test across both screws for 240Volt.
See if wires are loose.
If there is no reading, then breaker is not working on one leg.
To double check, move water heater wires to another same-size 240V breaker and then put ear against water heater to listen for bubbly-fizzing sound.
6) If you are getting 240 to water heater, then wire inside tank could be loose.
Do 30 minute troubleshoot:http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html
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