DIYbanter - View Single Post - Spa (Hot tub) Renovation

(Greg) wrote in message ...
Don't get me wrong. Solar heat can be a cost effective and workable
solution for the right climate and the right application. But doing
this to save the few hundred dollars a year it costs to heat a home
spa is not one of them.

See me in the spring. I am fix'n to try it. My real objective is pool heating
but I am going to dump the hot water in the spa and then the pool.
(from glazed collectors)
My results are not going to transfer well if you are in Frostbite Falls Minn
tho. I am in south Florida.
This is really more of an experiment than a plan. I know I can buy myself about
10 degrees in the pool, I am just going to see what the spa does. If the solar
doesn't work I do have 11kw of heat.

BTW if gas is cheap where you are it is a good option. My 11kw (a lot more than
most spas) is only about 37,000 btu. A decent gas heater is well over
100,000btu.

What you're doing in south FL sounds reasonable for many reasons:

Your spa is part of a pool, so the solar heat installation is saving
not just the spa energy cost, but the pool heating costs, which are
much larger than the heating costs of a typical stand alone home spa.

The climate is ideal

You have backup heat available

You're approaching it as an experiment, not a recommendation for
someone seeking to avoid the cost of a 240V line for a stand alone
spa.

I would also agree that gas is a good heat source for an inground
spa/pool combo like you have. However the OP has a typical small
stand alone spa. I've never seen one of these offer gas as an
alternative heat source. The gas heaters are all seperate high
capacity units, for applications like yours. I think gas is just not
practical for these types of spas due to issues like, could you fit
one inside the spa, where would the exhaust gas go, having to run gas
lines, etc. The cost savings are just not worth it, for the amount of
energy used, which is why manufacturers don't offer them. And trying
to backfit one into an existing spa with an electric heater is a lot
more cost and trouble than it's worth.