I've just inherited a working 8' wide spa (AKA hot tub), fiberglass body in
a foam-insulated wooden frame with an insulated lid, holding about 700
gallons. We're going to install this outside on what was a small (non-reg.)
basketball court, and put up a windbreak around it.
My county's building code requires a separate circuit to feed the 200A 240V
draw of its control panel (AKA 'pack'), dual-stage pump and electrical
heater. Installing that circuit, and the new panel it would require (as
the existing panel can't handle it) will cost $2,400, as per two estimates
from reliable electricians.
A hot tub manufacturer's website estimates it will cost $380/year
a) to run the pump on low by timer to keep it clean,
b) to run the pump on high when we're in it, and
c) to heat it to the temp most folks like.
That assumes our electrical rate is at its current 8.4 cents per KWH.
Has anyone here reworked a similar hot tub for gas heat? Or, for solar?
Natural gas and LP gas are much less expensive to heat with here (our
electric utility is owned by Enron, happy, happy, joy, joy), and if I can
replumb it to use an on-demand heater,
the heater would cost less than $800 and pay for itself in five years. It
also would reduce the size of the electrical install; I wouldn't need a
separate circuit and therefore would not need a new electrical panel.
I've also seen the Real Goods solar heating system. The Real Goods rep said
his Portland customers still need some heat in the coldest month or two,
but the rest of the time, no heat is required. This $1,900 (incl. motor
freight) system is said to be user-installable:
It would be nice to use the existing control system ('pack') but those can
be had for <$600
and could allow us, with pump replacement, to go 110V completely:
So, your comments regarding converting this spa to solar with gas, or
gars-only, would be appreciated. Thank you kindly in advance.
Nobody but a fool goes into a federal counterrorism operation without duct tape -
Richard Preston, THE COBRA EVENT.