The new design is inherently more efficient and more dependable than the original. Most of the existing pool heaters were standard-efficiency, non-condensing models and had copper heat exchangers which were in direct contact with pool water. Those are negative attributes, a trade-off for a lower upfront cost.
“Patriot provided a design along with a cost analysis including energy savings and lower maintenance costs,” says Rose. “We realized the payback for the new system would be less than four years. It became obvious it was the right time for us to make this investment.”
No down time
The entire pool heating system was replaced over two weeks in the spring of 2021. The installation was complicated as the pools and spas remained at setpoint temperature throughout the project. However, since the pump room was quite large, it allowed the old units to remain in service while the new system was assembled. The project was sped up even further by prefabricating much of the boiler system offsite.
The four boilers are piped into a single large primary loop, delivering 60 C (140 F) water to the secondary loop, leading to 10 360,000 BTUH titanium heat exchangers. The larger bodies of water require more heat than a single exchanger can provide; therefore, several of the heat exchangers are on a manifold to serve these loads.
The beauty of the common boiler system is how it responds to any call for heat very accurately, whether a single hot tub is calling for heat or all bodies of water are calling at once. As soon as the lead boiler reaches 50 per cent firing rate, the second boiler will fire at low input and increase its capacity as needed, and so on. The system’s staging controls rotate the “lead” boiler on a regular basis, this ensures runtime hours are balanced across all the units. Unlike the original system, this simplifies service and extends boiler service life.
In this system, the titanium heat exchanger takes the abuse from condensate, salt, or chlorine—not the heating appliance. Being titanium, they withstand the harsh environment very well. The system provides pinpoint accuracy in addition to longevity. Temperature in the pools and spas are maintained within one degree of setpoint, regardless of outdoor conditions.
“The maintenance and facility team are happy with the new system,” says Rose. “There was a considerable amount of apprehension about doing the work and taking some portion of the facility out of service, but Patriot made sure the pools were always open and at temperature throughout the project.”
