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Solar Pool Heating Systems

APEX Thermal Services installs five 4'x20' Solar Pool Heating Collectors, Millbrook, NY, Dutchess CountyAPEX Thermal Services installs five 4'x20' Solar Pool Heating Collectors, Millbrook, NY, Dutchess CountyAre you heating your pool with something other than solar energy?  If so, APEX Thermal Services can help you lower your pool heating bills considerably, or even eliminate them!  If You want to heat your pool, Solar Pool Heating makes much more sense than heating with electricity or an expensive fossil fuel.

If you or your family or friends (or club or workplace) are heating a pool with fossil fuels, please have them call or contact APEX Thermal Services.  There is huge money to be saved by installing solar pool heating equipment.  It can work stand-alone, or in conjunction with existing heating equipment (if the pool MUST be at a certain temperature).  This is often the case with larger institutional pools.  Conventional pool heating is VERY energy intensive, more so than heating an entire home, so the bills can be surprising and tremendous!  Residential pool heating bills can add up to $300 per heating event and, potentially, thousands of dollars per month if you set the thermostat and forget it.  For many of our customers, it gives us great pleasure to remove their old pool heaters and to take their pool heating off-the-grid, by making the most of our abundant, tax-free energy source.

So, what does it take to heat your oudoor pool with the sun?  Well, there are some variables to the system design, including how much shade or sun the pool gets, wind conditions, and the size of the pool.  When sizing a Solar Thermal Pool Heating System we are less concerned with the depth of the pool and more concerned with its surface area.  For oudoor pools, unglazed solar pool heating collectors are the most cost-effective approach.

If you have an indoor pool and wish to heat it year round, you will need to use either glazed flat plate or evacuated tube collectors.  This type of installation could be residential, or perhaps an indoor pool at hotel or college.  An advantage to this situation is that the system will be of adequate size to also make a large quantity of domestic hot water, or perhaps assist in space heating, lowering annual fuel costs even further!

Back to solar heating of outdoor pools: To somewhat simplify the solar array sizing approach, most pools will typically need unglazed solar panel surface area equal to about 50% to 60% of the surface area of the pool itself.  If a pool has a significant amount of shading or the customer requires system response more like a conventional pool heating system, it would be a candidate for a 75% to 100% collector area to pool area ratio.  At APEX Thermal Services, we install high quality Aquatherm Solar Pool Heating Collectors, proudly made in the nearby Garden State (NJ). 

Unglazed solar pool heating panels are typically roof or ground mounted.  In most cases, the existing pool pump(s) are adequate to provide the lift of the water to roof elevations. However, that is not always the case.  If your solar pool heating collectors are to be installed on a high roof, please be at least somewhat prepared to possibly need to upgrade to the next size pump motor.  For the record, we have yet to encounter the need for an upgraded pump.

Ground-Mounted Solar Pool Heating System - High Mount, NY, Ulster CountyGround-Mounted Solar Pool Heating System - High Mount, NY, Ulster CountyGround mounting of unglazed solar pool heating panels is an attractive alternative to roof mounting, and also lessens the possibility of having to upgrade the pool pump.  Obviously, the property must have adequate area for your array.

Some companies sell unglazed solar thermal panels (basically solar pool heating panels) for domestic water heating, as a alternative to more expensive glazed or tubular collectors.  Though they would perform well when it is warm outside, when the temperatures turn cold, they would be virtually useless.  If you are looking to only heat your domestic water in the summer spring and fall, unglazed panels may actually fit the bill.

Solar pool heating systems are controlled with solar pool heating controllers.  The controls are and function similar to solar thermal controllers (both technically referred to as differential controllers).  Solar pool heating controls are typically contained in a weather-proof/weather-resistant box, appropriate for mounting in outdoor locations (usually right near the pool pump or timer).


Indoor pools provide an interesting situation. If the pool owner is interested in year-round solar pool heating, you will need to use either glazed flat plate or evacuated tube collectors.  In these systems, the pool fluid will be pumped through one side of a heat exchanger, not directly through the collectors.  The solar fluid that is pumped through the panels and the other side of the heat exchanger will likely have antifreeze added, for freeze protection.  They will probably also be installing a fossil fuel system to provide heating for days when the sun doesn't show up for work.


With solar pool heating systems that require year-round heating, unglazed solar panels are not an appropriate choice.  Basically, the required system is a very large solar hot water system, using glazed flat plate or tubular collectors, with the capacity and size to heat a very large body of water.  Either a conventional or pool heating controller would be able to provide appropriate system control.
Stamford, CT, Eight 4' x 12' unglazed collectors are roof mounted on this home to provide pool heating.  APEX Thermal Services subcontracted to OnForce Solar on this Project.Stamford, CT, Eight 4' x 12' unglazed collectors are roof mounted on this home to provide pool heating. APEX Thermal Services subcontracted to OnForce Solar on this Project.

Remember, for any pool heating system to collect solar energy from the collectors, the pool pump needs to operate while the sun is shining.  Please keep that in mind when programing the pool pump timer.  A more sophisticated approach might be for the solar pool controller to start the pool pump when there is adequate energy to be collected.  Avoid control settings that would result in a lot of pump cycling, as this could shorten the life of your pump.

Solar Pool Diverter Valve and PipingSolar Pool Diverter Valve and Piping

Pool piping is typically done with PVC pipe.  Working with PVC pipe is relatively easy, though layout must be thought out before getting to far along.  Basically, near the pool pump, a motorized solar diverter valve and some additional piping and components are installed as well as the panels and connecting piping.  When there is adequate energy in the panels, the solar controller sends a signal to the motorized diverter valve.  This valve either sends the water on it's no-solar-available path (from the pump directly into the pool), or to the solar pool heating panels, and from the panels to the pool.  You can feel the heat at the water inlets of the pool, but considering the vast volume of the pool, it can take some time to heat up.  The heating is not as fast as that of conventional pool heaters, but your pool can get hot over time and the energy source is totally free!

Public pools, swim clubs, universities and hotels can benefit greatly from this technology.  Often times, they have temperature settings higher than that of residential pools.   Several years ago, when energy costs were less than they are today, I visited an outdoor swim club with an Olympic-sized pool, kept at a rather warm 84 degrees Farenheit.  Their seasonal pool heating costs were over $30,000!  Let's face it, the days of cheap energy are definitely behind us.  These days, heating a pool using conventional fuels, without employing some solar heating input is approaching insane.  If you have an area to collect solar energy, why would you just keep sending such volumes of money away, month after month, with the heat you purchased just slipping up into the atmosphere? 

Even if we get teased with lower fuel costs in the future, we should avoid taking the bait, as we have in the past.  Reduce your reliance on conventional energy sources.  Move closer toward off-the-grid.  Do something good for Mother Earth, our country and your pocketbook!  Yes, making the most of an abundant and free energy source takes an initial investment, but, after that, it is all savings from there.

Seven-Collector Solar Pool Heating System, Stormville, NY, Dutchess CountySeven-Collector Solar Pool Heating System, Stormville, NY, Dutchess CountyWhy spend thousands of dollars per year heating your pool?  Contact APEX Thermal Services to warm your pool in a more sustainable, earth-friendly and pocketbook-friendly way!