I am getting a hot tub this weekend and I have done some research and
still have some questions on my specific setup.
I will need a 240V 50Amp GFCI breaker for the tub per the manuf.
This is what I have now:
Main panel and subpanel in the basement
3 wire comming from the main panel (Square D 50amp 120/240vac AIC
10,000 breaker) going to the subpanel which has 2 breakers in the
middle that read 30amp for each one hooked together with a plastic
harness going out to the air conditoner then 2 15amp breakers on
either side for lighting in the basement. The wire going out from the
2 30amp breakers go outside to another panel.
Outside panel is:
2 wires going into the outside screws for the Line then 2 wires on the
inside for Load going into the air condenser, and both ground wires
hooked to a plate in the center screw. There is also a black
cartedrige that you pull out on this box, im assuming this is a
With that in mind this is what im planning:
I do not have any other available positions in the main panel for
expansion for my tub. So instead of incurring the cost to add another
subpanel now I would like to use the existing A/C subpanel for my new
Question #1: The wire going from the subpanel(inside) to the
disconnect box(outside) is a Type NM-B 600Volts 10/2 Operator 18. Will
this be good enough for the hottub load? (240v 40amp 60hz tub specs),
if not what size wire should I get?
Question #2: I think I will need to replace the subpanel breakers and
get 50amp 2 pole is this correct? If so I still need to have the 2
15volts there for my basement lights so will this be ok? Do they sell
50amp 2 pole with 2 15amp breakers? Basiclly I want to chage the 2
middle ones from 30 to 50 but it looks like its all one unit,so I
would need to buy a untit with all 4 this sound right?
Question #3: I should not have to change anything in the main panel
because its already 50amp 120/240Vac going to the subpanel right?
Question #4: I need to put the GFCI breaker somewhere since I already
have a disconnect box outside that I want to use for the hot tub, can
I just buy a GFCI type breaker that I described in Question 2?, or
does the GFCI breaker HAVE to be outside in viewable distance of the
hot tub, or can that be just the disconnect that I already have out
Question #5: I am going to run 4wire #6 AWG THNN Wire in liquid tight
conduit (copper wire) from the disconnect to the tub, does this sound
ok and the distance will be 30' is that ok?
Any other suggestions would be welcomed, also I have pics of all the
breakers/panels that I have mentioned if you want me to email them to
Thanks in advance
What wire is missing? You should have 2 hot leads, one from each pole in
that 240v breaker, a neutral, and a ground, for a total of 4 wires. You
have to have the 2 hots or you won't have 240v. You have to have a neutral
or you can't get the 120v for your lites. So no ground wire? Red Flag.
Save the long response to your post if you want. Your a/c subpanel won't
work if it's fed with 10 gauge wire.
There a lot of other things wrong with your idea, but the 10 gauge feed is a
No. You need 6 gauge copper THHN/THWN wire for 50 amps. Ten gauge is WAY
You will need a minimum of 6 gauge copper the entire length of your run, all
the way from whatever panel you place the breaker in, to the spa itself.
That includes the feed to that panel. Any less and you fail code, and risk
The feed to your sub panel must be large enough to handle the demand on that
panel. No matter what sub panel you tap, your main panel is what is feeding
the spa power. So starting from the main panel, all the way to the spa, you
need a minimum of 6 gauge copper. And 6 gauge copper is only good up to 60
amps. So if you are feeding a 50 amp tub, and and a/c and some lighting
circuits, 4 gauge copper may be in order from your main panel to the first
sub panel. That is good for up to 100 amps.
Also, does you spa need a neutral wire for a 120v leg? Most do.
No it does not. Have you ever pulled the cover off this sub panel? These
breakers should all be individual.
Something sounds a bit fishy here. Why do you want to pull your 30 amp
breakers? They must be feeding something, and you can't just increase the
breaker size. I supect these 30 amp breakers are protecting 10 gauge wire,
which isn't even close to handling 50 amps. Plus whatever these 30 amp
breakers is protecting (your a/c?) may require 30 amp breakers maximim.
Leave this be.
You need to add a new circuit for your spa.
This tells me that your sub panels are not up to carrying the extra load for
your spa. You can't feed a 50 amp spa, 30 amps of a/c and lighting circuits
off of a 50 amp feed.
There needs to be a form of disconnect no closer than 5' to the spa, and in
the line of sight from the spa.
This disconnect can be your GFCI breaker, or it can be any other code
approved disconnect. Mine is a 60 amp non fused a/c disconnect. You still
need the 50 amp GFCI breaker to protect the spa wiring, but it can be in
your main panel, or a sub panel, assuming that the sub panel meets the
capacity of your 50 amp feed. Ant that assumes that the wiring from your
main panel all the way to your spa is rated for the load it needs to carry.
I don't think you can do what you propose and still meet code.
Not to mention the risk of fire from overloading the wiring.
The NEC limits the length of this type of conduit to a maximum of 6', I
It is not allowed to have a 30' spa feed of this type of conduit. You could
use rigid PVC and transition to the sealtite once you get closer to the spa.
I suggest you dump the idea of feedint this spa from any of the sub panels
I also suggest you get real familiar with the code requirements for spa's.
They can be quite complicated. For instance, if your spa has a light, you
have to have the entire run of wire feeding your spa be in approved conduit,
all the way from your main panel to the spa. And this cable cannot be
romex, uf, etc. It must be THHN/THWN or similar. This is because spa's
with lights need an insulated ground from the source of power all the way to
the spa. Romex cable does not have an insulated ground. So if any of the
wire feeding any of your sub panels is out of conduit, or does not have an
insulated ground, you cannot legally connect your spa to it. If you spa has
no light, then this rule does not apply. Then there are bonding
requirements, and you need a 120v GFI outlet no closer than 10' to the spa.
Lots of rules, assuming you want to meet the current NEC code. And assuming
you life in the USA.
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