It may have been installed by an electrician but was it installed properly?
check for di-electric connectors, PROPER ground, heater grounded to a GROUND and not pipeing.
It sounds like element may be shorted out due maybe to electrolisis or possiably bad circuit breaker or overloaded circuit.
hot water heater should be on it’s own circuit ONLY!
Check the amperage draw of heater and compare to whats listed on lable and breaker amperage.
It may just be a weak breaker but check all of above.
good luck
Doug
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