On Tuesday, October 6, 2015 at 12:25:54 PM UTC-4, J wrote:
Thanks for all the replies. It'll take me a while to look through them all, but I got the answer I was hoping for pretty quick. So thanks. I love this group!

Some of the hot tubs I was looking at that come as 120v plug-n-play can also be purchased as 240v (hard-wiring required, with a more powerful heater and maybe some other additions - for an extra price). Other tubs appear to be sold as 120v only. My personal preference is to pay the extra $$ for a 240 model, but I did not want to be constrained when looking at tub, so it's nice to know that the wiring should be simple for an electrician.

As for converting a 120v to run on 240v, I guess you could do it if you made sure all the components could handle that, but I wouldn't want to risk it. For the tubs that I was looking at that come in both flavors, they often say that you if you have the 240v model, you can easily rewire it to run on 120v (but clearly, if you did that, you wouldn't be making use of the beefed up heater element that you payed extra for). However, the reverse is generally not true; you can't convert the 120v model to run on 240 - at least that's what the manual says.

Cheers.

I'm not sure there is actually a beefed up heater element at all. I
think it's the same element, they just put 240V across it instead of 120V.
It's fully surrounded in moving water, the temp rises across it's not much.