The only Whirlpool electric heater I know with control board is Energy Smart electric:
Open following link to identify product and download sample manual:http://waterheatertimer.org/Whirlpool-Energy-Smart-electric.html
First of all, the water heater is always full of water.
When you turn on hot water tap, hot leaves top of tank, and new cold water immediately enters bottom of tank through the dip tube. The tank never has air pockets as these would damage tank as explosive steam would fill that pocket ... remember they used to run locomotives with steam power.
So the tank is always full of water, and you know that since no air comes out of the hot water faucet.http://waterheatertimer.org/How-it-works.html
You did not say if this is new heater, or if heater was working correctly and stopped functioning.
What you describe does not sound normal.
I suggest calling Whirlpool at 1-877-817-6750.
You need to have serial number and model number from label on side of tank so product can be fully identified by Whirlpool.
If control board is bad, they will know and will sell you new board.
Installation is easy, and wires are color coded.
Replacement comes with instructions.
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