If you have the HWH that most of us have, the inside switch is for the gas burner to ignite. To use your HWH on electric, there is usually a small switch on the outside of your tank (usually to the left of and slightly above the anode rod) that you flip to "on." This will allow the heater to work on electric only, or you can use both the elements (electric and gas) at the same time for faster recovery.
NOTE OF CAUTION: Make sure there is water in the HWH before flipping that electric switch to "on." If your heater is empty and you turn it on, you will burn out your heating element faster than a teenager can say "huh?"
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2009 Salem LA 292fkds (gone)
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