Hello - I have a 6-7 yr old Whirlpool EnergySmart 50 gallon 5500 watt water heater. (Two control boards fried and were replaced free). Symptom now is not enough hot water. No 'error codes' are blinking on the diagnostic light. I have removed the control board cover and check for voltage to the upper and lower elements. After a long period of none-use, neither element is receiving voltage (normal). After some use, the current is directed to the lower element (orange wire), and the supplied water still properly hot. I then opened a high output (basement) faucet until the water became luke-warm. Lower element still energized. Shortly, a relay was heard and the voltage was directed to the upper (yellow) element only. All seems normal, except perhaps the upper element might have come on sooner to prevent the supplied water from becoming unusably cool. Is this likely an upper sensor that is no longer of proper 'calibration'? Is this device something whose value would change with time, or is it a type that would either be OK, or failed? (clearly it still functions enough to trigger the switching the system from lower element to upper). Maybe I expect too much, but this seems to be a recent change in our domestic water supply. I also notice that the number of the control board has changed (last digit)(my boards look the same, unlike other writer whose first board lacked a reset), and that the heater in stores is now supplied with 4500 watt elements. Is this an industry wide change, or has Whirlpool perhaps found that their relays can't handle 5500W? I have 10 gauge wire, 30Amp breaker.

Sorry to see you're having problems! Can you contact me directly so I can help?
www.whirlpoolwaterheaters.com/help
Thanks ~ Chris

1) Residential water heaters are non-simultaneous. Only one element works at a time.
Upper element comes on until top of tank is heated, and then lower element is switched on until lower part of tank is heated. Lower element keeps tank hot during standby hours
http://waterheatertimer.org/How-it-works.html

2) Typical Whirlpool energy smart has 4500Watt elements. Look at label on side of tank
If both elements were ON, that would draw 9000Watts or 37.5 amps, requiring 50 amp breaker and 8 gauge wire. V x A = Watts.
All dual-element tanks are 240V.
Whirlpool energy smart requires 10 gauge wire and 30 amp breaker so electronics are not starved during operation. If your wire or breaker are undersized, that is suspect for repeated failure.
http://waterheatertimer.org/Whirlpool-Energy-Smart-electric.html

3) Typical electric water heater heats 21 gallons per hour. First hour delivery is higher since elements heat water as you use it. Overall however, electric water heater cannot re-heat as fast as gas because gas water heater burner carries more BTU punch per minute than electric element. Gas heats about 41 gallons per minute, with higher first hour delivery.

4) IF YOU HAVE OLDER energy smart and installed newer board, then you could have non-simultaneous operation is reversed so that lower element comes on first.
Read following post at Fixya:
http://www.fixya.com/support/t8263226-our_water_heater_doing
Contact Whirlpool 1-877-817-6750

5) Another potential problem is that you have sediment inside tank and that is reducing efficiency of lower element.
http://waterheatertimer.org/Clean-sediment-out-of-water-heater.html
http://waterheatertimer.org/How-to-test-water-heater-element.html

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