Anyone use solar only to heat their spa?

[DrippingPool]

Does anyone use only solar to heat their spa and have no gas heater? We would like to skip the propane heater on the spa to save money and energy. We are in the Austin, Texas area and have lots of sun, so I think our climates may be similar.

We are going to have a 7 ft square spa, next to the pool, completely in ground, with spill over into the pool when in recirculating mode. As I understand it, when we put it in spa mode it does not recirculate to the pool.

Can you run the solar till the sun goes down to keep it at a certain temperature, then how many hours later can you still use it?

In April our average temperatures are highs in the 70s lows in the 50s. Will the spa get hot in April?

Thank you!

 

[Pool Clown]

I don't know about your personal preference, but...
The majority of people that i deal with, like to spa at night, not during the day while the sun beats down on them...
You can cover the spa for use at night, but if the temp drops past your comfort level, you have no recourse till the sun comes back up the next day.

 

[mas985]

We like to use the spa at night and during the winter, both when solar is useless. As PC points out, our least favorite time is when solar works the best, during very hot days. However, I will sometimes pre-heat the water during the day with solar so the heater doesn't need to run as long when heating at night but that only works well on hot days.

Without a heater, the spa's use will be significantly reduced and given what you are spending for the pool and spa, it doesn't seem like a good trade-off.

 

[DrippingPool]

Yes, not being able to use the spa in the evening/night was definitely what we're worried about. I was *hoping* that we could run the solar until close to sunset to keep the warmth up and then it might hold some heat for an hour or 2, but it sounds like that's not the case. Good to know that someone who has solar is really glad they have another heat source.

Better to know before we spend the money! It does sound like solar heat for the spa alone won't be worth the $5000 price tag a solar company gave us. But I've learned a lot on this forum and we might try the do it yourself route!

 

[Safetybob]

I just gave an extensive answer in another thread here around using solar and since it was cheap, easy and since it was going to be temporary, resistive heat. My small pool is operated very much as a large spa would be.

Solar (and it was small too) did keep the heat on the pool/spa good but as soon as my insulated cover came off, you could feel the pool getting cooler within 15 minutes, 30 minutes.......yup, much cooler. That was when outside temps would have been upper 60s to lower 70s during the day. I am in Oklahoma City, so little bit north of you. We came outside after sundown alot after dinner in the spring, and early summer and pool was taken out of service on December 15th......

With superior insulation along the sides and top of your spa, heat loss will be kept to a minimum. For me, once I tighted down the heat loss, operating cost (with an 11KW electric heater) wasn't even noticable on the power bill. If I knew I was going do a spa, or small AGP thing permanently, I would have a gas heater. If you can do new, great. On a budget or looking out for your financial wellbeing.....craigslist. I think last year there was at least one nice gas heater on craigslist for the entire year continuosly.......most of them for 25% of new. If it worked a season or two, great, look for another or get that new one.....

Bob E.

 

[ps0303]

If you like your spa around 100 like most people, then a gas heater is the only way to go. Plus it would heat it on demand and more efficiently than anything else.

Yes you can take a chance and purchase one on craigslist but I wouldn't do that unless it is currently hooked up and the seller can show you that it does work. I would also let to run for about 10 minutes to make sure it runs good. A quick turn on and off can hide problems.

 

[Nova13]

I'm installing 4 glazed solar panels on our spa total 72' solar they will run thru a heat exchanger 150,000 btu, smallest I can find for about $140.

the spa is only 300 gallons so the water should hit 100-104 easy.

If in the evening it cools a bit the electric heater will kick in I suppose, still will cost less increasing the temps a few degrees rather than 30 if the air temp is 70 for example.

 

[DrippingPool]

Thanks to everyone who is chiming in - I'm still watching the comments, learning a lot and getting new ideas!

The solar system we had priced was for the whole pool and I hadn't thought of putting in a smaller solar system for just the spa. I also hadn't thought of looking into the cost of electric heaters if it was just supplemental.