Is this wire sized right?

[StaggeringGoat]

My new shop condo has a small 3600w instant water heater for the sink like this one:
http://www.grainger.com/Grainger/CHRONOMITE-LABS-Water-Heater-6DXT2

Specs are 120v, 30A, 3600W. It's hooked to a 30A breaker using #10 romex in a pretty long run. That just barely works...but I thought you weren't allowed to use 100% of the wire rating 100% of the time? In other words the max draw on a 30A breaker should be only 24 amps....shouldn't it? (80%)

Is this heater installed correctly? I haven't got the power turned on yet so I can't tell you how well it actually works or not.

 

[mrb]

point of use instant water heaters arent considered continuous loads. The manual for yours says 30 amp circuit so youre fine as far as circuit ampacity. How long is 'pretty long' ? I would have used a 240v model...only 15 amps..

 

[StaggeringGoat]

How long is 'pretty long' ? I would have used a 240v model...only 15 amps..

I'd guess about 60 feet of wire. I would have gone with a 240v (208v) too, but it wasn't my choice...

 

[Norcal]

I'd guess about 60 feet of wire. I would have gone with a 240v (208v) too, but it wasn't my choice...

208 & 240V are not the same.

 

[StaggeringGoat]

208 & 240V are not the same.

Thank you captain obvious.

 

[mtne]

60' isn't long enough to worry about voltage drop...