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AprilRose
04-17-2006, 07:02 PM
Well, we are just about to begin our second full summer with a pool. We have really enjoyed having it and enjoyed the low maintenance of the salt water system. I am trying to attach a picture here. We have the Cayman Green finish on the plaster for those who wonder what it looks like. A beautiful turquoise blue.

Now, for my question. We are thinking of having solar heating added. Can anyone offer any advice? Also, do we have to go with the company we used to avoid altering our warranty?

Thanks!
AprilRose

schirico
04-17-2006, 08:01 PM
Solar heating is GREAT! I had an AG last year and had 2 panels, 20 foot long each hooked up. The only thing was my fittings in my filters etc. were 1.5 inches and the solar panels were 2 inches, so I had to get a whole bunch of converters to change diameters etc.

My Solar heat was not automatic, and I would highly recommend it for 2 reasons....

1. you can set the temperature and it will shut off automatically so you don't turn your pool into a jacuzzi (my pool hit 97 degrees last year with solar panel and solar blanket - talk about an algae problem!).

2. it can shut off automatically at night, solar panels will make your pool ICE cold at night and remove all heat you put in during the day, so this is a nice feature.

I don't have them yet for my IG pool, but after I put a new roof on the house, I will put solar panels up.

don't let anyone tell you that you need a larger, more powerful pump because you put panels on the roof either, the water coming down will pull create a suction that helps to pull other water up into the panels, etc....

Poconos
04-17-2006, 08:15 PM
The only trouble with solar on a roof is getting the air purged initially. For this, depending on factors like pump size and how the panels are plumbed in, all pump output thru them or only partial, there may be some startup issues because you now have to raise a column of water without the assist of the downhill side.
Al

tphaggerty
04-17-2006, 10:24 PM
Solar panels are great! Especially with propane and electric going through the roof. I have a new pool and installed solar straight off. During October of last year in New York, we saw a net rise of 1 degree per day running at only 6 hours per day with about 55% coverage (solar panels to pool size).

However, there is no "air purge" problem. Any (correctly installed) roof system will be designed to "drain back" into the pool when not running. There MUST BE a vacuum breaker installed close to the high point of the panels in order for this to happen. This means that the system is full of air everytime it turns on and will blow air into the pool for the first 30 seconds or so of operation. This is true of roof top systems, it is not true of smaller systems that are at or below pool level. Drain back puts much less stress on the solar system (no pressure build up due to expanding water as it heats, no water weight on the roof and piping when not running, and, the biggest issue - no reverse pressue trying to collapse those expensive panels as the water tries to drain back into the pool but can't). All of the major manufacturers install as drain back.

The biggest issue with solar is that it is harder to run an efficient pump, as the THD is normally higher than the low speed of a 2 speed pump can handle. My builder pretty much refused to put in anything but a 2HP pump, so I am looking at alternatives myself.

We installed 8 4x14' panels for an 800 sq/ft pool. I have just opened for my 2nd season, but am expecting to be swimming in 80degree water within a week or two!

jmc61894
04-19-2006, 03:51 PM
Hi, I live in Mass and iam looking into solar for heating my IG. what brand of panels did you use?

tphaggerty
04-19-2006, 10:00 PM
They are SolarIndustries panels. I have 55% coverage on an eastern facing roof, not the best setup as I lose the late afternoon sun, especially in the early spring and late, late summer. One nice thing about SI is that you can get a good variety of panel lengths, I wound up going with 8 4x14 panels, the extra 64 sq/ft was worth it (ran out of roof length or I would have added another panel). I have an Aqualogic controller.

I have the system running now, it has raised the pool temp from 51 on opening to 59 now in about 3 days of running. I expect the kids to be swimming in a week or so. The system keeps running for at least 1/2 hour after the sun has left the roof, it just sucks the heat out of the roofing tiles!

CPM
04-22-2006, 10:21 AM
A LONG time ago, when I was in college, I worked at the Florida Solar Energy Center testing collector performance. I quickly learned that there is a big difference in the performance of hot water solar collectors. I just went to their site and they have performance ratings on pool solar collectors posted. Looks like most of the pool collectors are about 1000 BTU/Ft2, but there are some that are a lot less. I recommend you check out their site to see if the collector you are considering was tested, and has a rating from the FSEC.

http://www.fsec.ucf.edu/solar/testcert/collectr/tprpool.htm


Craig
UCF class of 1980

CarlD
04-22-2006, 01:41 PM
I, too, am an advocate of solar. It's free heat! Sure, it doesn't work when it's raining--but we don't swim then.

You don't NEED an automatic system if you set your manual valve(s) so it(they) are convenient. I turn them on in the morning before I go to work, and off when I get home, and don't use them if the water is getting too warm.

I had 96 deg water last summer...Algae is ONLY a problem if you neglect your water, not if you are checking it everyday--and adjusting as needed.