Steve B wrote:
There is much argument/debate/discussion/hysteria over the
advantages/disadvantages of leaving it on all the time, or leaving it where
it will maintain a constant temperature.

3.
This debate would be among people who know nothing of 300-year-old
physics? :-)

Yes, I have to agree with that one. There is absolutely no question
that lowering the temp on a spa, for any period, then raising it back
up for use, saves energy. The rate of heat loss is proportional to the
temp difference.


"That, of course, depends on the ambient temperature...

Of course not.

Nick "

I agree with that too. How much you can save by turning it down
depends on ambient, but not whether you can save.