Breaker Size

[donnie]

What is the max. breaker size for a 240v , 4500w ,55gal water heater.
If I use art.422.13, I come up with a 25a. But I have been told that I could use art.422.11 (E)(3), and then I come up with a 30a.
Which one would be code compliant ?

 

[ryan_618]

Re: Breaker Size

I think either one would comply. I would use 422.13 because it is the more specific requirement, where 422.11 (E)(3) is more general. A 25 or a 30 amp breaker would comply though. Either way you are looking at #10 wire.

 

[wildman]

Re: Breaker Size

imo...max. breaker size is 30...422.11(E)3..shall not exceed 150% of appliance rated current.....min. breaker size is 25...article 422.13...not less than 125%. both look ok!

 

[pierre]

Re: Breaker Size

If the concern is for maximum size, 30 amp is the only answer, if your concern which will work, either of them will work. For test question purposes, only the 30 amp answer would be correct.