I am installing an older dimension 1 hot tub and the specs on the tub label say 240V/30A for power requirement. Most info I have read and seen online says to use a 50A double pole breaker in my power supply box but is this correct or would I use a 30A? And what gauge of 4 wire line would I use for either, I planned to use #8AWG-Cu.

Also wondering if NEC code still allows to use a GFCI breaker at main power box and simple power disconnect outside 5ft or more from the tub or do I have to use an external GFCI that also works as the disconnect which does satisfy my local code for such and a standard breaker at the box?

Always refer to the manufacturers instructions and nameplate ratings to determine the minimum size of circuit rating.

You may use # 8 wire, but if you use Romex cable then you can only protect the #8 with a 40 Amp breaker.

If you use any other cable or pulled THHN wires through a conduit, then you may use a 50 amp breaker on #8.


Sure the GFI breaker can be at the panel, the benefit is that the entire circuit is now GFI protected. For convenience , you may want to consider having the GFI breaker closer to the tub, you may use it as the service disconnect switch at the tub.