The manual has nothing in it about repairing the water heater. If the water heater has a hole in it, this is the time to replace it. If the water heater electric element gasket is leaking, this is a matter of replacement. If one of the pipe or adapter threads is leaking, that is to be repaired.
Hey, Don’t forget the relief valve!!That could be leaking also. check the temperature of the water should not be over 120-130 degrees Far. If the water is too hot check the thermostat-s. If the water is ok replace the relief valve, if it is leaking,