Curious question about my water heater
I was inspecting my water heater the other day & I noticed something odd on the faceplate:
Both the upper & lower elements are 4500W, but the instructions on the plate say to wire with #10 Cu & to use a 30A breaker (which is how it’s wired).
What gets me is that you have two 4500W elements (totalling 9000W).
At 240V, that’s 37.5A
What gives?
Replies
Magic.
Actually, as is the case with most dual-element electric units, only one element is on at the time.
The upper element has "priority" and if it's on it turns off the lower element. This allows a small amount of water to be heated quickly.
Once the water at the top is hot enough, the upper element goes off and the lower one comes on, to heat the rest of the tank.
That would explain it. Mystery solved.Thanks