Water heater breaker keeps tripping

[edsmax]

Whenever I go to turn my hot water heater switch to "on" in the main switch panel in the galley, the "main" switch for the galley switchboard pops and goes to the off position. Suggestions? Grounding issue? Anyone experience this before? If I leave the hot water switch turned off, everything is fine.

Ed

 

[boatmailster]

possible: short in the system - possible burned wires on heater or shorted heating element, low voltage from dock, bad breaker

disconnect wires from heater and try again: if trips look for short in wiring, if not check heater and breaker

 

[tobnpr]

Odd that the main would trip and not the breaker for the heater.
If the heater were faulty, the heater breaker should trip before the main. Is the main 30 amps?