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Parts for Whirlpool KESC307HBT1 Range - AppliancePartsPros.comSee the attachment for the tech sheet
I am assuming that you mean the DLB relay not the DMB.
[COLOR="Blue"]Strange, shows 110v to Broiler elements and Convection Element on both sides, but not 220 across leads.[/COLOR]
With the DLB relay closed this would be normal. I am assuming you are referenced to Neutral. You will see the L2 voltage at both sides of the elements. The element is just a resistance so the voltage will feed through it.
For some reason the element is not getting the L1 voltage.
If it was OK then you would also see 120 volts on the L1 side of the element but it is 190 degrees out of phase with the L2 voltage so you get 240 across the element and it heats up.
I am assuming that this was a live test so the DLB relay was closed and the voltage was at all the element at the same time (L2 side). If this is not the case and you saw the voltage at individual elements re: only voltage at inner broil element when it econo broil. Then the problem is on the L2 side.
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L1 Bi metal NC to Control Bd. OK, Oven Fan NO Bi metal OK! Are there any other fuses that are not visible. Oven has hidden bottom baking element![/COLOR]
As far as I know you have checked everything.
When you checked the thermal cut-out did you use the mist sensitive meter scale to be sure it is 0 ohms. Also did you disconnect one side of it. This is important so that you do not read an alternate/parallel circuit path.
Does the unit stay in preheat or does it show ready?
Unplug the unit and check the resistance of the wires/connectors of the power to the board and elements.
Here is my theory on the above. If you have a bad connection then this is a resistance. As long as you are not pulling any amperage everything will look normal. Lets say this resistance is 1000 ohms. When the elements call for power all the voltage is dropped across this resistance and it would limit the current to a 0.24 amps.
There is always the possibility that you received a defective control board.