Outside The Box

Mechanical contractor H&G Systems, Garland, Texas, has been providing its expertise on dehumidifying natatoriums for a number of years. The company has worked on several indoor pool applications all over the state of Texas.

H&G Systems was able to share its knowledge of packaged dehumidification units during a natatorium project for the Carrollton-Farmers Branch ISD school system. Mechanical engineer Robert E. Cliver, P.E., of Estes McClure Associates Inc. (EMA), was responsible for designing a dehumidification system for the 120- by 75-foot indoor pool.

Cliver designed a field system that combines an air handler using coils coated with an anticorrosion enamel, a remote condensing unit, and a reheat system that would use compressor heat to warm much of the pool water to around 82 degrees F.

This design had been used successfully several other times by EMA for other schools. But a problem arose when this project started to run over budget. EMA, as well as other trades working on the building, were asked to start thinking outside of the box in order to keep construction costs down.

H&G Systems and manufacturers representative McMillan Choate & Associates approached EMA about using a packaged dehumidifier in order to save on installation and operating costs. The recommended unit was a Dry-O-Tron™ packaged dehumidifier by Dectron Internationale, Montreal.

Saving More Than Money

EMA decided to give the Dry-O-Tron a try. The company said it was a tremendous success. First, by using the packaged unit, EMA was able to save money on the project. By specifying a packaged dehumidifier with factory-mounted controls and an uninsulated duct, an estimated $35,000 was saved from the original project bid, which brought the project under budget.

According to Kirk Fitzgerald, president of H&G Systems, the packaged unit helped the school save money in more than one way.

“The simplicity of having a complicated system packaged with on-board controls actually saves cost on the installation, and will continue to save operating costs during the system lifetime,” Fitzgerald said. “The control systems applied to field-built systems are sophisticated as well, but I’ve observed past systems to be operated improperly by maintenance personnel who do not fully understand all aspects of the system. This will cause excessive energy inefficiency, poor control, and premature failure of components.”

Fitzgerald added that installing a packaged unit over a field-built system provides operating benefits for building managers.

“The ability to control humidity is a complex process,” he said. “By installing a package system you remove the operator error from the equation.”

The Dry-O-Tron packaged system monitors all of the various processes going on in the environment. It can also alert building operators when a problem is occurring and what that problem is.

Another benefit of using the packaged dehumidifier was space savings. The unit saved over 500 square feet in the mechanical room because the Dry-O-Tron unit was installed on the outside of an exterior wall. Fitzgerald said that in other natatorium applications his company has worked on, the unit has been placed on a rooftop.

Future Projects

The decision to use a packaged system on the Carrolton-Farmers Branch project has prompted EMA to do the same on other natatorium designs. The company specified a packaged dehumidifier on its next project: the 40,000-square-foot Carroll ISD Aquatic Center in Southlake, Texas.

EMA took the design one step further and also installed Dectron’s on-board 2,200-mbh and 1,750-mbh boilers to the custom RS-462 and RS-282 Dry-O-Tron units. The units serve two separate pools, a 180- by 75-foot pool and a smaller 30- by 40-foot warm-up pool.

Decker Mechanical, Cedar Hills, Texas, installed this system, which recovers compressor heat in order to heat the pool water and space reheat for winter operation. The interface on-board boiler serves as a back-up pool heater while eliminating the need for a conventional swimming pool heater.

“Even though we’ve designed a lot of field-built systems in the past, we’ve established a company design standard now that a packaged dehumidifier will be used with an indoor pool now, simply because of the finished product’s quality, lower first costs, less space used, and ease of design,” said Cliver.

H&G Systems also continues to use the Dectron units for its natatorium projects. The company has become a leader in the state of Texas as a mechanical contractor that knows the ins and outs of installing and managing a dehumidification system for indoor pools. In fact, H&G was recognized by Turner Construction as the “Subcontractor of the Year” for its work on the Carrollton-Farmers Branch ISD project.

Fitzgerald said each natatorium project brings its own challenges and each job is different, but he contends that Dectron’s packaged units have made the job easier. H&G has been using packaged dehumidification units since the early 1980s. According to Fitzgerald, many of these systems are still in working order today.

Publication date: 08/11/2003