Hot tub wiring questions

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 Subpanel is:
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 disconnect box.
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 hot tub.
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 there?
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 you
Thanks in advance Jason
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NO 10-2 is rated for 30 amps. From what I understand your going to need a service change. Sounds like you have a 60 amp service and you want to add an additional 40 amps for the spa.

See above
on #4: I need to put the GFCI breaker somewhere since I already

The gfci can be located inside and the disconnect outside is fine.

Liquid tite is commonly limited to under 10 feet here abouts. Your area may not have that restriction
me to email them to

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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 show stopper.

No. You need 6 gauge copper THHN/THWN wire for 50 amps. Ten gauge is WAY TOO SMALL. 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 fire. 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 believe. 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 you describe. 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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