[dunbar]

xtreeme - that is not how power panel loads are calculated. I built my house, my wife and I wired it and everything, and I was there when the utility company put the transformer onto the power pole in my yard, which transformer feeds only my one house. I noticed it was a 15 kVA transformer, and told them that didn't make a lot of sense for 200 Amp service, which would be 48kVA, not 15 kVA. They told me that I would not likely run everything on my house all at once, thus the 15kVA would be adequate. 24 years later, it still works fine, the utility company was right - I do not run 200 amps all at once.

As for the heater causing only one side of the circuit breaker to get hot.... to me, that means the breaker for the heater (and should be only the heater on that breaker) is seeing heavy load on one side, and much less load on the other side. Water heaters are needing 240 volts which means ideally no current flowing in the neutral, right? Which tells me there is a current flowing through neutral somewhere. Or possibly that one screw was less than tight. I hope it was the screw part and not the load part.