New Tub Wiring

[djmatte]

So we went with the signature spa and got it installed. The problem we ran into was the gfci cable was tooshort (accessed in back and not front like old tub). The problem I am running into is what cable to get to lengthen it. Here are the spec requirements from the old and the new tubs:

New: GFCI box and pack terminal block is required. Your spa requires a 4-wire, 50 amp or 60 amp (depending on the spa model), 230 volt subfeed in non metallic pipe to the spa equipment compartment.

Old: Power hook-up to the spa must be 240 volt 3 wire plus ground

(6 AWG copper).

Under those paramaters, I am presuming the original gfci box is running at 240v. Would this work for the new tub which is running at 230?

My next concern is the 3 to 4 wire conversion. Can I simply exchange the wires or would it need a whole new plug within the box to support?

Any help or thoughts would be appreciated.

[PreservedSwine]

230 vs 240 are the same thing. BUT, you need to run an extra wire. Many manufacturers use the same control box across all spa platforms (120v and 240v) so even their 240v models require a neutral wire so the control box can run properly 120v. Your old spa was true 240v, all components, including the control box circuitry, so no neutral was necessary. You just need to run one more wire. Also, there shouldn't be a plug on a 240v line, I would suggest ditching any "plug," and run the wire directly from the GFCI subpanel to the control box.

[djmatte]

Ok I sorted out the issue with the wiring. Turns out it is the exact same gauge and amps as the last tub. So my next dilemma. The only cable sold locally was a 55 amp wire. If 55 amp wire is running off a 50 amp circuit, can this cause any problems to the tub or circuit box? (tub is a 50 amp tub)

[PreservedSwine]

I'm not sure what you mean by a "55 amp wire?" Wire just comes in different sizes, The maximum amp load for any size wire is determined by the length of the run, as well as the amp load. At any rate, just follow the manufactures guidelines. They probably call for an 8 gauge wire for a run less than 100 feet. If you're doing it yourself, and you're not pulling a permit, after confirming what the amp draw is on the neutral line, you can probably use much smaller wire. The neutral will be used to carry the current of the 120v volt components only. Check the voltages of the jet pump, air blower, and cir pump. If they all 240v, you can use a 14 gauge neutral. If they're all 120v, you're going to need a 10 or maybe even 8 gauge wire to be safe, depending on the length of the run.

[Spa_Guru]

All convertible voltage spas use 120v pumps unless someone has replaced it with a 240 v model and relocated the pump white wire on the circuit board.

Using #6 copper for the new power leads is always a good idea, the smaller the wire, the larger the voltage drop, and the hotter the board and pump windings run.