Pool And Ice Rink Control
Proper ventilation and dehumidification strategies can maintain a good relationship between the occupants and the water in its various forms.
Few areas can be as tough to condition as pools and ice rinks. Indoor pools, or natatoriums, need to be able to maintain a space temperature warmer than the water temperature (generally around 84°F) and space humidity between 50% to 60%. Most ice rinks need to hold a space temperature of 70°F with humidity below 50%, although new NHL standards would like to see 65°F with humidity below 40%.
In addition to these challenging space conditions, these projects are further challenged by the presence of large volumes of water in the pool or on the rink and the need to provide proper ventilation (as well as isolation from adjacent spaces). Conditioning these spaces is always energy intense; however, there are strategies that can be used to provide the needed conditions as efficiently as possible.
While it may be possible to condition these spaces with conventional packaged or applied systems, most designers choose to use specialized units that are specifically designed for these challenging applications. Most of these dedicated systems are constructed of materials designed to deal with humidity and chemicals and include the ability to heat, cool, dehumidify, and ventilate. Since they are very specialized systems, they almost always come with a packaged control system.
When evaluating a new pool or rink application or looking to improve the performance of an existing system, there are several things to keep in mind in terms of controls and control strategies.
Setpoints. One thing that can be done to improve efficiency and performance for even the most basic packaged units is to ensure that the setpoints are properly configured. For most pool units, this means a temperature setpoint that is 2 degrees above the pool water temperature, along with a humidity setpoint of around 60%. These setpoints tend to result in reduced pool evaporation and overall lower energy use. For ice rinks, you should look carefully at the operational needs of the rink. Hockey rinks generally need harder ice that requires lower humidity and temperatures, while other rinks can tolerate higher temperatures and humidity.
Use of outside air. The current trend in conditioning these spaces involves an increased use of outdoor air when conditions are appropriate. In many climates, cool, dry outdoor air may be all that is required for much of the year. The use of outdoor air for conditioning generally requires more sophisticated controls and sequences. These may be available for new packaged systems but can also potentially be applied to existing systems as well.
Ventilation. Pools and ice rinks should generally be kept at a negative pressure to adjacent spaces. Proper ventilation needs to be provided per code, and additional ventilation may be needed to “purge” the air under certain conditions to remove contaminants. While these spaces need to be conditioned at all times, it may be possible to provide fewer air changes when the space is not in use.
Integration. We would strongly encourage that the controls from a packaged pool or ice rink unit be integrated into the BAS. This allows for these key areas to be monitored for both operational and energy efficiency. If software integration is not possible, then we would recommend adding sensors for the BAS to monitor space temperature, humidity, and key items of unit status.
While controlling natatoriums and ice rinks is a challenge, it is possible to effectively meet the requirements and to do it in an efficient manner.