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First, you are correct---you should not be using 2 single pole breakers, you need a double 50 amp breaker to supply an electric range
. This could be a major fix if it requires replacing the wire through your house along with the breaker.
Second, this will not cause the issue with the broil element being warm all the time. If the broil element is warm, it means that the element is grounded out and is failing (so it would need to be replaced), or the display board is failing and the relay is sending a little bit of power to the element when it shouldn't. You'd need to disconnect the wires from the back of the element behind the oven and test power between the 2 wires. You should not get a reading when testing one wire to the other (approximately 0 volts). If you have more than that, then you'd need to replace the display control board.
As for the manual, Whirlpool owns Inglis and up in Canada, you'd need to contace Whirlpool to get a copy of your manual if that is possible.
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