Balboa spa user manual

Unless it's a 110 tub, you don't. If the system is designed to run on 220 the circ pump and flow pump will not function properly, the power pack may not function and the tub will never reach temp. If it is a 110 hot tub I would still suggest having a licensed electrician run the line for you. Most insurance companies will not cover any type of hot tub related claim unless installed by licensed tub tech/electrician. If you insist on wiring it yourself, the BLACK wire is the "hot" wire carrying the current. In 220 installations the RED wire is the second "hot" wire. The WHITE/GREY is the neutral wire, and the GREEN is the ground. But again, I STRONGLY recommend paying the $80-$95 bucks to have it done professionally. I hope this helps =)

For $80-$95???
thats the deal of a lifetime, maybe two?

anyway, many spas are dual voltage capable...
you need to read the inside of the control box schematic! Usually on the cover... If you see 'convertible' or how to wire for 110 & 220, then follow the appropriate wiring instructions.
if only 220 volt wiring instructions are present, then you can't use a 110 supply.
NORMALLY, 110 units will have a cord with a GFCI on it. If there was no cord, chances are you can't use 110.