replying to Burhans, albert wrote:
Yes that's correct about the NEC code. If your installation going to be
inspected, technically a 20 amp breaker using 12 ga. wire can be rejected. and
you would need to find a 26 amp breaker, using 10 gauge wire.
I'm also installing a Rheem 20 gallon 120V 2000 watt water heater. People ask
why not a 240?, which are more common. The reason is I only have 120 Vac
service for a motorhome where the 20 gallon (point of use) water heater being
installed. No 240 service means no 240 equipment, water heaters, stoves,
driers, welders, etc.
However problems occur trying to find a 25 amp circuit breaker. Hardware
stores don't usually carry them. If they do have one or two such as at Home
Depot they may only fit certain types of service panels.
My RV service panel accepts a max. of 9 (one inch wide) breakers (including
the main) and uses standard square-d single pole breakers for the home (1 inch
wide). Most of it's breakers in the rv load center are dual breakers.that save
space.
I'm also adding an AC 120V 20 amp outlet next to the water heater. After
looking around could not find a 20/25 amp dual breaker. The local ACE hardware
carried no 25 amp breakers. Home Depot had a 25 amp breaker but wasn't the
right type to fit my load center.
A 30 amp breaker might not trip or trip in time when connected to a 2000 watt
heating element. So I for now I'm going to use a 20 amp breaker (20/20, 20 amp
for the water heater and 20 amp of a 20 amp AC outlet)
If wanting a dual breaker I haven't been able to find a 20/25 amp dual breaker
anywhere. Perhaps a store such as Platt electric might have such a breaker?
I'm using 10 gauge wire. Purchased 20 feet 4 x 10 gauge. Hot, hot, neutral
and ground. $1.96 per foot to be installed into 1/2" PVC conduit as the main
part of the run is outdoors. Metal Clad can be used outdoor only if protected.
PVC can be used indoors, outdoors and underground.
Another option would be to swap out the 2000 watt heating element for on
that's under 2000 watt such as a ~1700 or ~1800, etc. watt element. Then one
can use a 20 amp breaker with 12 gauge wire and be up to code.
--
for full context, visit
https://www.homeownershub.com/mainte...ter-11154-.htm