Deciding On Ductwork

Comfort and proper airflow were the two most important requirements for the HVAC system in the New Jersey building. "The facility has floor mats for exercises, parallel bars, rings, etc., so basically you've got people who are in all different parts of the building," said Gene Alligood, vice president - commercial division, Hannabery HVAC. "Airflow was an issue because the owner didn't want air blowing directly on the gymnasts who were trying to do something on the parallel bars, for example."

The high ceilings posed a challenge for proper airflow. In applications such as these, either spiral ductwork or concentric ductwork is usually used. Alligood ruled out both types because there would be too much airflow concentrated at one spot.

"Once we decided against spiral and concentric ductwork, we took a hard look at a fabric duct system," he said. "We looked at performance versus first cost, and it really met the criteria for both."

FabricAir ductwork was chosen for the facility because air seeps out of the ductwork instead of being thrown out of a register in various locations. The ductwork is available in a variety of colors, and the company can even fabricate the ductwork in custom colors to match the facility. The gymnastics facility had blue mats installed, so matching blue fabric ductwork was chosen.

Alligood hadn't installed a fabric duct system for several years, but the new generation ductwork really won him over. "There's a tremendous savings in labor to install fabric duct," he said. "For jobs that would normally take several days, it sometimes takes only a few hours to install a fabric duct system, versus one using spiral, metal, or fiberglass."

Up On The Rooftop

Almost every square inch of the gymnastics facility is taken up with floor mats and equipment, so there was no extra space for mechanical rooms. With the high ceilings, it wouldn't be feasible to hang equipment all around the building, as the raised and padded floor mats are very expensive, and placing a ladder on them to service equipment would not be possible.

For these reasons, two 20-ton Rheem rooftop units were placed on the building. The gas heat/electric cooling units are equipped with economizers, so on mild days, the facility has the opportunity to utilize outside air instead of mechanical cooling.

A larger-than-normal crane was needed to lift the units onto the roof, but the installation went fairly smoothly, Alligood indicated. Ease of service is a concern, as the units are only accessible by way of a tall ladder on the outside of the building. The owner has been advised to install an inside ladder on an available mezzanine with a hatch leading to the rooftop, but no action has been taken at this point.

"When we installed the units, we had to rent a platform lift that would go up 40 feet, so we were able to do what we had to do," stated Alligood. "Now it's a challenge to get up there and change the filters. Most technicians don't carry around an extension ladder that goes to 35 feet, so that's a big concern right now."

While the rooftop units take care of heating and cooling the main area in which the gymnastics classes take place, other equipment was needed for additional areas of the building. The perimeter areas of the facility, which include a retail area and a few small offices, are serviced by a 2-ton Rheem heat pump.

"The heat pump worked out well, because we didn't want to run additional gas piping all the way over there for a small area," noted Alligood.

A 5-ton, 90-percent-efficient Rheem furnace uses LP gas to heat the main lobby area. An air conditioner was also installed on this unit. This large, high-traffic area needed a furnace that would quickly heat the space, so the cold air coming in through the front doors wouldn't travel across the room into the area with the gymnastics equipment. A Honeywell T7300 thermostat gives the owner of the facility a number of programming options.

By all accounts, the budding gymnasts have been comfortable in their new training facility.

Publication date: 06/14/2004