By Tom Soukup
There is great opportunity in the aquatics industry to advance pool heating systems. Key areas in need of improvement include water temperature accuracy; downtime elimination; fuel, electrical and space savings; maintenance reduction; filtration efficiency; component life cycle; system longevity; and return on investment (ROI).
These improvements can be accomplished through proper system design, even if the design is unconventional. More often than not, the author’s company draws on their experience in the hydronic heating industry to create pool heating systems with condensing stainless-steel boilers as well as titanium heat exchangers.There is great opportunity in the aquatics industry to advance pool heating systems. Key areas in need of improvement include water temperature accuracy; downtime elimination; fuel, electrical and space savings; maintenance reduction; filtration efficiency; component life cycle; system longevity; and return on investment (ROI).
However, in certain applications, using conventional pool heating equipment offers the best solution. Pool heaters provide a lower upfront cost per British thermal unit (BTU) of installed capacity compared to boilers.
Ultimately, for the author’s company, the design and control strategies are what makes their systems unique.
Planning for innovation
Direct-fire pool heaters—typically high-efficiency units—are ideal for outdoor bodies of water designed for seasonal use. In these situations, a great deal of heat is required to bring the water up to set point temperature during start-up in the spring. Far less heat is then needed to maintain it during the season. Many of these applications also require the heating system to be installed outdoors. While conventional pool heaters are built for outdoor installation, few boilers have the same capability.
The industry standard approach to an application like this is to install a single pool heater to handle the maximum heat load, which only occurs once each year, during start-up. The main issue with this method is if the unit fails, there is no redundancy, and immediate downtime is the result. There is also a litany of other issues which stem from a conventional approach.
From a hydronic perspective, the author’s company has learned to use the lowest number of BTUs needed to satisfy a call for heat, based on current environmental conditions. Whether the heating equipment is condensing (high-efficiency) or non-condensing (conventional), short run times are the enemy of efficiency and longevity.
Using a single, large unit sized for maximum demand means to maintain set point temperature, the unit will fire frequently, for very short periods of time. Not only is this inefficient and hard on heating equipment, but it can also create unstable pool temperatures.
