How Geothermal Pool Heating Works: A Closer Look at This Energy-Efficient System
A breakdown of our geothermal pool installation and its energy-efficient heating and cooling system.
Ever wondered how big pools stay warm without running up sky-high energy bills? We recently installed a geothermal pool heating system at Doral Aquatic Center, and it’s making a huge difference. Not only does it keep the training pools at the perfect temperature, but it also runs efficiently and sustainably.
This was such an exciting project, so I’m breaking it down to show you exactly how we made it happen—covering everything from filtration and heating to power and plumbing. You’ll learn how large-scale pools can be heated (or cooled) efficiently without wasting energy. Here’s what you need to know:
How the pool filtration system works. The competition pool uses six high-flow sand filters, while the training pool has its own system. Water is pulled in, filtered, and sent back out—clean and ready for swimmers.
To integrate geothermal heating, we added bypass valves to control water flow. If the bypass is open, water skips the heaters. If it’s closed, water passes through the heating system before returning to the pool. This setup ensures precise temperature control without disrupting filtration.
Geothermal heaters for efficient pool heating. We installed 14 geothermal heaters; 10 for the competition pool and four for the training pool. Instead of using gas or electricity, these heaters pull heat from underground well water through a heat exchange process. It works like an air conditioner in reverse.
To make monitoring easier, we use Pool Sync, a remote system that tracks temperature and heater performance through a phone app. If an issue arises, we get notified immediately, even before the staff notices. This ensures fewer interruptions and consistent water temperature.
Geothermal heating is a cost-effective, energy-efficient way to heat large-scale pools, saving you thousands over time.
Smart heating management system. With 14 heaters running, managing energy use efficiently is crucial. The primary-lagging system ensures they work together and prevent wasted energy. As for the primary unit, it acts as the leader that coordinates the others so no heater cools while another heats. This keeps the pool at a steady temperature without unnecessary fluctuations.
Plumbing design for durability and reliability. The heaters are plumbed in parallel to ensure even water flow and prevent wear on any single unit. Since Florida is prone to hurricanes, we also reinforced the system with hurricane tie-downs and vibration pads. Even after major storms, the heaters have remained secure.
As for easy maintenance, we installed Spears ball valves on every heater connection. If one unit needs servicing, it can be isolated without shutting down the entire system. This keeps the pool running without downtime.
Electrical setup and pump efficiency. Each heater has a dedicated breaker, so turning off one unit won’t affect the rest. We also installed Variable Frequency Drives (VFDs) on the well pumps. These adjust water flow based on demand, which improves efficiency and extends pump life. They also protect against power surges to keep the system stable.
Well system for sustainable water heating. This system relies on well water. We drilled three supply wells to pull warm water from underground. After heat is extracted, the cooled water is returned through three injection wells. Then, they naturally flow back into the aquifer and eventually into the Atlantic Ocean.
Of course, to make sure the system lasts, we used PVC casing set deep into the limestone and reinforced it with concrete. We also used lock pipes instead of glued fittings to make future maintenance simpler.
This geothermal system is a smarter and more energy-efficient way to keep the water at the perfect temperature year-round. If you have any questions or want a free quote, give us a call at (941) 474-9306. We’d love to check out your property and see how we can help you save thousands on your heating costs.
