Does this exist?
I want a switch/outlet combination, where if the switch is thrown one way
power goes only to the outlet, and when thrown the otherway it goes only
It would be like a three-way switch combined with a single outlet.
It is for use on a 20a circuit, but there could never be more than 15a on
the circuit. (switched one way it powers a 13a waterheater, the other way a
single 15a outlet) Will a 15a switch be adequate, or must I have a 20a
You only need a 15A switch although there's no harm in a heavier duty one. It
is the weakest link that'll size the breaker. IE: if you have a 20A switch,
but 15A wiring and a 15A outlet, the breaker can be no larger than 15A.
if the 20 amp circuit uses 12 awg *copper* wire, it will support a
20amp switch. a 15 amp switch, depending on how cheaply made it
is will have a fairly short life cycle running the 13amp water heater.
If the '20amp circuit' is using 14 gage copper wire it is illegal,
and potentially unsafe.. in that case replace the 20amp breaker with a
15amp breaker. or pull 12 gage copper wire.
You can use either a 20 amp or 15amp switch/recepticle on 12 gage
wire... the key issues are wire size big enough to carry the current
allowed by the panel circuit breaker.
additionally these electrical ratings have two aspects... the peak
rating and the continous load rating. For instance a 20amp rated
recepticle can carry 20 amps for brief intermittent loads but not more
than 15 or 16 amps continuous (I forgot the exact figure, its listed
on the box).
So that yer 15 amp switch on a 13 amp hot water heater is probably
half an amp over its continous load rating.... depends on the duty
cycle of the water heater if its considered a continous or
intermittent load. i would consider it continous since it is possible
someone could use hot water heavily resulting in long run times.
When powering motors or continous loads it is a good idea to purchase
the more expensive options of brand name components... you can get
away with the cheapest options on light duty, intermittent loads, such
as occasional lights etc.
(If you use aluminum wire it must be sized at least one wire gage size
larger to carry the same load as copper wire, see the relevant NEC
charts for that sizing and application, use anti oxidant grease on any
wire connections when using aluminum wire... not many people
recommend aluminum wire, its prone to corrosion.)
The switches themselves are common. Look at the switches used for
situations where more than one switch controls an outlet. But I don't
know about finding one with an outlet in the same form. I've never seen
that configuration. You'll probably end up having to use a 3 or 4-way
switch and a regular outlet in a ganged mounting box.
Yes, that just barely fits within usage specs. Ideally the load should
be 80% of max and 13/15 = 0.866667 ; a tad over 0.800, but it should be
Technically, that number says you want 20A; it's borderline above 15A
for a constant current draw.
If as you seem to say it's on a 20 A breaker though, everything,
wire, outlet, switch must be rated for 20A.
If it's on a 15A breaker then 15A OR 20A components would be OK since
only 15A can flow. But plugging in a 20A product may pop the breaker.
I'd opt for 20A IF the wire size was compatible (eg 12 ga wires). If
it's 14 ga, then you're stuck with 15A or a rewire. 14 ga is normally
used for lighting ckts.
Assuming copper wire, not aluminum.
I agree 13A is just over what should be connected to a 15A switch. I
think a water heater would be a continuous load (over 3 hours).
15A receptacles can be (and very often are) used on 20A circuits. The
restriction is if only one receptacle is connected it must be 20A (the
common duplex receptacle is 2 receptacles).
15A switches can be used on a 20A circuit. The switch must match the load.
A 20A receptacle on a 15A circuit is a code violation.
You have a 120V water heater?
You can never make assumptions about the load. You have to assume
that it is possible for some idiot to attach a 100A load. Or for the
load to short out and try to draw hundreds of amps. The breaker
must open before the weakest link blows. In your first scenario, the
outlet will burn up; in your second scenario the switch will blow.
Never ever use a breaker designed for a amperage greater than your
What I described has been code (and standard practice) for a long time.
There are probably far more 15A receptacles on 20A circuits than 20A
receptacles. You are welcome to suggest a code change. Be sure to
describe the dead bodies - helps a lot in getting your code change approved.
15A receptacles are essentially the same as 20A receptacle.
In another example, breakers can have a much higher amp rating than
conductors for motor circuits. And welder circuits make motor circuits
look tame. Both have been common practice for a long time. Where are the
The NEC requires that "snap switches shall be used within their
ratings." For example "resistive and inductive loads ... not exceeding
the rating of the switch." [Ratings may differ from that on the device,
such as for motors.] It has been thus since the beginning of time. Where
are the dead bodies?
Write a proposal to change the code. Be sure to submit your pictures of
Really dumb question. Doug likely knows a lot better than you.
BTW Doug, IIRC the new code requires common disconnect for all poles of
a multiwire branch circuit. I think that was one of your pet peeves. You
may have already seen it. There was actually a dead body associated with
Combo devices do exist, e.g. the Leviton 5245. All you need is a
3-way switch (SPDT) and a single receptacle on one yoke. You can then
wire the receptacle to be controlled in the fashion you describe.
I'm not sure if your application is a good idea, though. What are you
trying to achieve by having a switch to select between a water heater
and a receptacle?
I am trying to run a circuit for a new water heater. The panel box doesn't
have any knockouts and I really don't want to cut one. There is little box
with an outlet in it just below the box. I can run my water heater to the
little box and steal that circuit, but would then lose the outlet. It would
rarely if ever be used, but still...
By doing this, the outlet would be available if it was ever needed.
(Also, it is bolt on breaker, which I would prefer to avoid dealing with if
The Leviton 5245 is only 15a, so if I need a 20a switch/outlet it won't
work. The box only has room for a single device. I can replace the box
with a bigger one, and may have to.
There are many different ways to solve this problem; I am just looking for
the easiest way. Also, I am kinda stalling. The room the water heater is
in is miserably hot and humid; so I am waiting for cooler weather.
No offense, but it would be better just to cut a new hole in the panel
box for the new circuit. The simplest way would be to make a small
starter hole and then slowly enlarge it with a step drill bit until it
is the right size.
If you are dead set against putting a new hole in the panel box, then
you could use the hole that is feeding this outlet box, and just pass
the new circuit straight through the outlet box. This may require a
larger outlet box.
Oh, fer cryin' out loud. Just run a new line to the water heater from the
outlet box. Pigtail the connections to the outlet, so that power doesn't have
to pass through the outlet to get to the water heater.
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