It Makes Your Cold Pool Warm
SolarCraft's solar pool heating systems work seamlessly and are fully automated. You set the desired water temperature on the solar control panel, and when solar energy is available at the solar collectors, an automatic motorized valve diverts the existing filtration water through the solar panels and carries the suns heat back to the pool. This process is continued until either the pool's filter pump shuts off or the desired pool temperature is reached. In most cases the existing filter pump can easily provide adequate flow to the solar panels, and there is no additional electrical expense. The only requirement is that the filter pump needs to be operated during the day, (10 AM to 4:30 PM). This is the time most pool professionals would recommend your filter be operated regardless of whether you have solar or not. It is the time the pool is most likely to be used, and the time when good circulation and distribution of sanitizing chemicals is required.
The solar collectors installed by SolarCraft are incredibly efficient. Under normal operating conditions as much as 90% of the suns energy is converted into heat for the pool. The FAFCO Revolution solar collector is certified by the Florida Solar Energy Center, (FSEC), to put out 1063 BTUs per sq ft, per day. This is the highest rating ever given to a solar pool collector. The comparisons can be viewed at http://www.fsec.ucf.edu/en/certification-testing/STcollectors/pool_ratings/tprpoolap.htm.
Before FAFCO introduced the modern polymer solar collector in 1969, copper solar panels were the norm. Copper is reactive with the common chemicals in pool water. Pool equipment manufacturers and builders have done everything possible in recent years to eliminate copper from pool plumbing and equipment. Today over 90% of the solar pool heating systems installed use some variety of polymers or stabilized polypropylene. The advantages are numerous.
Efficiency: The only place heat transfer occurs in a solar collector is where the water actually touches the panel surface. Copper panels are constructed with relatively large, (½”), tubes spaced several inches apart, with a fin between that greatly reduces the “wetted surface”. Copper panels typically have 10 to 12 tubes across the body of a 4 ft wide panel. FAFCO Panels, made of stabilized polypropylene, have 240 very small tubes side by side, with no space between. Every square inch of the solar panel has water running through it for a “fully wetted” surface and greatly increased efficiency.
Longevity: Common sense would lead us to believe that metal copper solar panels would outlast those made of a plastic such as polypropylene, but that is simply not the case. As soon as pool water begins rushing through copper panels, some of the copper is leaching out into the water. Additionally calcium and other minerals in the pool water begin to collect on the inside surfaces of the waterways and reduce heat transfer. In our experience, even with good pool chemistry, copper panels often begin to leak after 8 to 10 years as the copper is removed from the tube walls. Great care must be taken to turn off a copper solar heating system when performing pool maintenance. Even one instance of having the system operational while the pool’s pH is incorrect, or while adding acid, can shorten the panel’s life significantly. The patented material used in FAFCO panels is not affected by exposure to pool chemicals. Just in Northern California there are thousands of FAFCO pool heating systems that are over 20 years old. One of SolarCraft’s owners has FAFCO panels heating his pool that were manufactured in 1979, and they are still going strong!
Another material that has come and gone on the solar pool heating scene several different times over the years are “tube mat” systems made of a rubber material, (EPDM). The material used in the bodies of these collectors is not specifically designed for use in solar pool heating. It is purchased in bulk from large manufacturers who designed it for other applications such as defrosting sidewalks and driveways in cold climates. The owner’s manuals and warranties of these products often contain many warnings and exclusions regarding discoloration of the pool water and exposure to common pool chemicals. Often they warn of having water remain in the collectors when the system is not in use, even though the systems are designed with the tubes running horizontally across the roof, or the systems are installed flat and cannot be easily drained.
Collector Location and Orientation
Generally speaking the solar collectors for spring, summer and fall pool heating are most efficient facing slightly West of Due South on a slope of about 20 degrees, (3/12). That said, the fact is that we have systems facing due East and due West that work very well. Systems can also be installed flat or on a roof slope of 45 degrees. Your site and aesthetic concerns dictate solar collector placement. Small deviations from the ideal stated above have very little effect on performance. As we get further from the ideal, we simply add square footage of solar collectors to compensate.
Each site and each pool is different. Over our nearly three decades in business in the North Bay we have installed solar energy systems in a variety of ways. Roof, Ground Rack or Trellis Mount are all possibilities depending on the particular site. We use a variety of tools to estimate pool heat demand, flow requirements and sun and shade tracking to determine what will work for your situation.
Due the many variables, it is difficult to estimate system size and cost without a site visit. Upon request, one of SolarCraft’s knowledgeable and experienced consultants will visit the site to discuss your pool heating and energy needs and provide a free assessment and estimate. We have a large library of photos of previous installations, and will show you product samples so you will know exactly what a system would look like at your site.
Occasionally upon a site inspection, we determine that due to shade, aesthetic concerns, or space limitations that solar pool heating is not feasible at your location. We will be the first to tell you if we cannot install a system that will meet your needs, and will not install a system that does not meet our design criteria.