A water heater heating element will not increase resistance and draw more power. It does not act like a motor.
Your most likely cause is going to be a poor connection at the service pedestal or when the wires connect at the converter. Feel the plug at the pedestal. Is it warm or hot? Do the blades on the plug appear to have been overheated? At the converter are the wires from the power cord scorched or showing signs of overheating? If you find this to be the case you will need to remove the connections and cut of the bad wire ends to get clean copper. You may have to use a wire brush and sand paper on the terminals to clean those up.
Something is causing a drop in voltage. The water heater is about a 1500 watt load. But it, itself, is not causing the problem. It is merely the item that causes the real problem to become apparent.
Chuck - Sparta, TN
2012 Jay Flight 22FB, 2 x Honda EU2000i
2013 GMC Yukon XL Denali AWD
EDUCATION is what you get when you read the fine print.....
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