Fans

Manatee County Water Treatment Lab

The Manatee County Water Treatment Lab is a multi-lab building used to test water quality for customers serviced by Manatee County. The lab is located on the western end of Bradenton, FL, about three miles from the Gulf of Mexico. The lab collects water samples throughout the county to ensure all distribution systems meet the Safe Drinking Water Act regulations. This involves utilizing various concentrations of chloramines (chlorine + ammonia) as a disinfectant. 
 

The lab contains multiple fume hoods and general exhaust which are served by high plume lab fans mounted at the top of the building. Due to the critical tests the lab performs, the fans are designed with N+1 redundancy. With the close proximity to the salt water of the Gulf and the nature of the tests being run in the lab, the existing high plume fan suffered significant corrosion. As a result of the corrosion, the steel fans did not meet the original design airflow, which caused room pressurization issues.

A team from Manatee County Government (Owner), and Advanced System Engineering (Mechanical Engineer), worked with Tom Barrow Company to solve this problem. The owner wanted a fan that could hold up to both the environment and various lab chemical tests. The constraint was to fit the existing curb of the steel fan and avoid upgrading any electrical.

Tom Barrow Company partnered with MK Plastics to develop a solution. An inline high plume lab fan and plenum were proposed. The entire fan assembly and plenum were constructed of FRP. This included the casing, impeller, and velocity cone. The new fan was able to meet the design airflow and static requirements without increasing the motor size from the existing fan. This also allowed the fans to be connected to the existing VFDs.

The FRP inline fan was mounted on a plenum that was custom sized to the fit the existing curb. The final assembly was 30% lighter than the existing, thus no additional structural modifications were needed. A FL PE stamped, high-wind load analysis was conducted based on the latest Florida Building Code. This provided the contractor with details on how to properly secure the fan to the structure.

“We were able to provide the end user a product that will last and perform in a lab that plays a critical role for water in Manatee County,” shared Cyril John, Sales Engineer – Tom Barrow Company, Tampa.

MK Plastics was founded in 1963, and they are the global leader in the production of corrosion resistant industrial and commercial blowers. The fans manufactured are AMCA certified for both air and sound performance. 
 

UF College of Veterinary Medicine FANWALL Retrofit

The two large vaneaxial supply fans (70,000 cfm & 125 Hp each, 8.6 in.w.c. design static pressure) in the main air handler at the UF Veterinary Medicine build- ing had been problematic for several years, due to both the age of the fans and the logistics of keeping the AHU off-line to make repairs. The solution was to retrofit a FANWALL in place of the vaneaxial fans. A FANWALL retrofit, with its “building block” assembly style and customizable dimensions, permitted easy assembly into the supply fan plenum, and was built in two sections matching the existing internal dimensions of the air handler.

During a low-occupancy period for the building, one fan was kept in operation while the other fan was taken off-line and replaced with a FANWALL array. Once the new FANWALL array was installed and operational, the opposite vaneaxial fan was replaced in the same manner. While no reduction in connected load was made, the owner reports that they are now getting air to areas that previously had never received sufficient cooling, and the change to FANWALL has eliminated extended/expensive repair outages.

Schermerhorn Symphony Center

On May 1st and 2nd of 2010, Nashville, TN experienced nearly 14 inches of rain leading to the worst flood in the city’s history. Many homes and businesses suffered terrible losses, including the Schermerhorn Symphony Center. The Nashville Symphony’s 197,000 s.f., 1900 seat home originally opened September 9th, 2006. The center was designed to be a world-class symphony hall and has been a very successful venue since its opening. The mechanical system design includes eleven custom air handling units. Of these, ten were completely submerged in the flooding along with all of the building’s electrical equipment, instruments, and organ.

Having constructed the building originally, American Constructer’s, Inc. was re-hired by the Nashville Symphony to perform flood remediation and reconstruction. ACI, in turn, hired Lee Company to remove all damaged equipment and reinstall a new mechanical system. The original system utilized single plenum fan AHUs in custom cabinets with large motors. The units serving the performance hall were all stacked top and bottom units. All of the units had to be cut out and removed piece by piece. The replacement AHUs supplied by Tom Barrow Company incorporated FANWALL® Technology for acoustical performance, space savings and for the capability of getting new custom units back into the building.

FANWALL® Technology

The original project’s acoustical requirement’s were extremely stringent and required a Performance Noise Criteria (PNC) of PNC-10 in the performance hall and PNC-30 in most surrounding areas. Acoustically, the Huntair units were designed so that they were less than the original AHU’s radiated and discharge sound power levels. Using the 4” thick panels with perforated liner to match previous unit construction and utilizing FANWALL Technology’s direct drive plenum fans, this task was easily accomplished. In most octave bands, the Huntair air handling units were 15+ dB better than the original AHUs! As a result of this better acoustical performance, over 25% of the sound attenuation that was to be replaced was eliminated from the project entirely. This in turn reduced the static pressure on the overall system.

Six of the original ten air handling units were stacked units to account for the space required by large single plenum fans. ALL of these units were reduced to a single level by the Huntair design. The gained vertical space was used for future flood remediation. The Huntair units were set on elevated structural steel that raised the base of the units six feet from the floor of the mechanical room. Turbine pumps have been installed in the space beneath the units so that this space can be used as a sump pit in the event of a future flood. Because of the reduced unit height, enough water can be removed from the building that a flood twice as large as the May flood will not damage mechanical or electrical equipment.

The ten AHU’s that were replaced are located in equipment rooms that are 20-30’ below building grade. The Huntair air handling units had to be delivered completely knocked-down so that all of the pieces could be brought in through a grated outside air opening that ran twenty feet deep. It would have been impossible to bring in motors or fan wheels to match the original units without knocking down one of the Symphony Center’s beautiful Neo-Classical exterior walls. This fact made FANWALL Technology the perfect solution for the project, since all of the fans could be brought down in their cubes individually. After eighteen truckloads of palletized equipment and approximately 6,000 man hours, the units were brought in and completely assembled in the mechanical rooms. Besides the installation benefits FANWALL Technology has provided, the owner is now realizing ease of maintenance and better building performance!