Help a brother out. Where I live (other side of the pond), the standard household plug has a circuit-breaker capped at 8 amps, but the voltage is 220V. That would mean I can draw 1760W from a standard plug (kettle and microwave being about 1500W max).
If I do the math, with a little help from the link below, to heat 4 gallons / minute from 22C to 60C would require about 44kW. If this tankless solution is 99% efficient, then it will draw 45kW.
That is 25x the power my plug will let me draw, so "point of use" will require a special high-voltage/amperage connection like an oven or stove.
But indeed from their website, they do say you need a 30amp connection. However, even at 220V, 30 amps will only give me 6.6kW, and this device needs 45kW.
Are they using heat exchangers from the drain water to help pre-heat the incoming water? Or is the website simply out of date? Or, the more likely scenario, have I gone terribly wrong in my math?
Clearly they wouldn't have won any awards for their design if the device didn't do what it claims.. but I'm just curious from a scientific standpoint what the claims are.
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