GSW electric water heater displays E103 and trips the breaker when heating

Safety: Turn off the breaker and lock it out if possible. Do not reset repeatedly without repair.

• Visual inspection: Remove access panels and inspect wiring for bare copper touching the tank or metal covers. Repair any damaged insulation.
• Test elements for ground fault: With wires removed and power off, measure resistance from each element terminal to the metal tank. Any reading other than infinite indicates a ground fault; replace that element.
• Check element rating: Ensure replacement elements match the GSW nameplate voltage and wattage. Oversized elements can overheat and fail.
• Breaker and wiring: If elements test good, have an electrician verify the circuit breaker and supply wiring are correctly sized and in good condition.