Warming up your pool for June in Maine

By Tom Gocze, BDN Staff
Posted June 06, 2009, at 1:23 a.m.

Hey, it’s a pool party — everybody in the pool! Uh-oh. The pool is only 65 degrees Fahrenheit.

It is time to use your swimming pool, if you are fortunate to own one.

The problem is that in June, many pools here in the glorious state of Maine are in microclimates that are similar to late March. There are pools that warm up naturally and are luxurious spas, but there are others that might be fit for polar bears.

If I had the joy of pool ownership, I would want it to be 85 degrees for the entire season. As one who has installed a lot of solar pool-heating systems over the years, I feel that is the magic temperature for pool users.

If you are someone who likes to jump into a frozen Maine lake or ocean in January, stop reading NOW.

One absolute no-brainer for investing in solar heating is pool heating. You do not need tax credits to make the investment work for you. It is a very simple system and there are many varieties of solar pool-heating systems.

The basic solar pool-heating collector is made from polypropylene plastic and consists of a lot of small-diameter vertical tubes that are connected to an upper and lower manifold.

The collectors hook together and use the pool pump to circulate pool water directly through the collectors and then return it to the pool. This is a simple system that can be a do-it-yourself installation and pay for itself within a year or two.

A commercially installed system might cost $2,500 to $3,500. A similar fossil fuel system might cost the same and consume a similar amount of fuel each year it is operated. You also can use a heat pump to heat your pool, but why even think about paying for fuel when solar heating a pool in the summertime in Maine makes such sense?

You can build your own collectors. Many people tell me about putting coils of polyethylene tubing on the roof to heat their pool. This can be a little crude, but there is no denying that the concept of diverting cooler pool water up to a hot roof where it picks up heat to return to the pool is simple.

Once again, I will refer to the Web site www.builditsolar.com. There are many do-it-yourself pool-heating concepts there that you can do for a fraction of the commercially available systems.

One system that is not on this Web site that I find intriguing is an indirect solar pool-heating system. This concept uses a fancoil, which is basically like a car radiator. The fancoil is installed in an attic vent and a blower vents the hot attic air out through the radiator, which heats pool water that is circulating through it. Any uninsulated building roof builds up enough heat in summer to allow it to be a very effective solar heater.

A couple of caveats for the novice solar pool heater builder:

1. Try to avoid using metal in your installation. Even copper might cause problems. Always use PVC or polyethylene tubing to plumb your system.

2. Do not undersize the lines that run to the collector(s). Pool plumbing is usually 1½ to 2 inches in diameter. Maintain that sizing; otherwise you might damage your pool pump.

3. Invest in a pool solar differential controller. This is a control that compares the collector and pool temperatures. It allows the pool to be heated only when the collector is warmer than the pool. This integrates with a three-way pool valve. These two items usually sell together as a set and might cost a couple of hundred dollars, but they make your system automatic. You can be frugal and operate your system manually, but the controller will allow much quicker heat-up in the early season and better efficiency for the entire pool season.

4. If you operate the system manually, you must remember to shut the solar system off on cool nights. Operating at the wrong times will work backward and cool the pool down.

This is a fantastic and fulfilling do-it-yourself project that will make your pool investment a lot more comfortable and affordable.

Questions for Tom Gocze should be mailed to The Home Page, Bangor Daily News, P.O. Box 1329, Bangor 04402-1329. A library of reference material and a home-project blog are at www.bangordailynews.com/thehomepage.html.

http://bangordailynews.com/2009/06/06/living/warming-up-your-pool-for-june-in-maine/ printed on September 18, 2014