Cameo uses a Suburban Water Heater so it will have an OEM ON/OFF switch for electric element in outside compartment (lower left corner)
Also.Hi temp t-stat could be tripped.
'Push To Reset' cover above gas valve.
Left one is for 120V AC element (Right is 12V DC propane)
Trips on HI temp 170*F
120V AC connects to HI then goes to Normal via a connecting wire then to element
Connecting wire can burn thru....remove cover and check
If not tripped then Element could be bad/shorted
Under oval cover below gas valve
120V AC across the two terminals with Switches ON and water temp below 100*F.