Electric water heater disconnect

[Richard Roshak]

The temperature at this knife switch disconnect for a 66 gal electric water heater was 104 degrees. I have never touched these while the appliance was operating, so I have idea if this is a problem. What do the masses say?

[Jon Randolph]

Did you remove the cover to see what the wires looked like? It is a good idea to do so.

What was the power requirement for that water heater? Looks like 10 guage conductors, but can't tell for sure. Are the wires heavy enough to carry the required current? Does the disconnect support the required current?

[Jim Luttrall]

Richard, around here a 104 degree disconnect would be about right for an attic installation if you caught it early in the morning before the sun heated things up.

I have a feeling though that your ambient temp may be a little lower and your heater may be in a basement rather than an attic.:D

Seriously though, a little more info would be good. I suspect your instincts were correct and there may be a problem in the disconnect. I would not expect any increase in temperature in a switch like that unless there was a problem. The only heat generating parts in that switch are wire and contacts which would not generate any appreciable heat when operating inside the normal limits.

[Tim Voss]

Fahrenheit or Celsius?

104 Fahrenheit is only 40 Celsius, not a problem.