A rant on fresh water pump location....

I'll let someone else explain the details to you. Just be aware that the thing is a pump, not a water heater, it runs on AC and is an inductive load so the power calculation must include power factor. The motor is probably around 80 percent efficient so only 20 percent of the real power might be converted to heat. Until the entire pump is heat soaked the amount of heat transferred to the water is not, as you indicated, equal to the entire power input to the pump.