Answer

If you want to do this install yourself, you can easily do it as long as you follow a few of the applicable codes. Now first off, if you have a main panel on the outside of your house, then you will need to feed this circuit from there. The NEC states that you need to pull any wiring for a pool, spa, hot tub etc from this location. If you dont have an outiside panel, then this rule will not apply. But this rule will apply to both: For this install you will need to run 6/3 aluminum serivce cable (2 hots / neutral / ground) or 8-3w/ground copper. Additionally at the new subpanel, you will have to install a separate grounding bar and remove the bonding screw to keep the neutral and ground seperate from eachother.

From there you will need to run the circuit from the sub-panel to the spa in conduit, either PVC buried under ground or sealtite, which is flexible conduit. In this conduit all your conductors will be thhn wire see pic for example:

Now I would recommend using a 1" conduit for this only because some models of spas will require a separate 120v 20amp circuit in addition to the 50amp for running low voltage lights, radio control panels etc.

If you were to hire an indipendent company to come in and do this for you, expect to pay anywhere between $400-$800 dollars depending on the contractor. Now this is based on the contractor prices down here in florida, may be slightly higher or lower where you live.

Hope this helps. If you need anything further or need clarification on anything I said, dont hesistate to ask. Have a great day.

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