Facilities that store a large number of musical instruments need precise humidity control. Many instruments, including string instruments, are made of thin wood which are easily affected by temperature and humidity. This can be a challenge when retrofitting older air handling units that, in many cases, are using outdated technology that is neither precise nor energy efficient.

Location: Memphis, TN

Owner: The University of Memphis

Mechanical Engineer: Haltom Engineering, LLC

Mechanical Contractor: Damon Marcus

Manufacturers: Temtrol Custom Air Handling Units, Condair (Nortec) Humidifiers

The University of Memphis found themselves in this situation when looking to retrofit and replace the existing AHU in the basement of their Music building. The scope of the project included the replacement of six units and the addition of one new unit, but with the strict requirement that the replacement units would fit on the existing equipment pads and match up to existing duct and piping arrangements. To accomplish this was a challenge due to the fact that the existing units were older multizone units that did not have an effective humidification system. The University also wanted to save energy by eliminating any steam generating humidifiers. They requested an atomizing humidifier, which while typically requiring less energy to run, would require a much longer AHU footprint than what the existing equipment pad could fit. One last challenge was the access to the basement, as some of the units needed to access the area through a standard door into the mechanical room from a hallway.

Temtrol’s custom AHUs provided the best solution. Their ability to provide a completely custom footprint so as to match the equipment pads, while also allowing custom openings to match the existing supply air zone duct, was a huge labor savings for the contractor. The coil sections also came with custom dimensions to match the existing connections, and by using FANWALL Technology, the unit could be sized to include more components in the air stream without sacrificing the unit footprint. Some of the AHUs shipped as “Rapid Knock Down,” assembled at the contractor’s shop with minimal screws and without sealant. The contractor marked the units based on their scheme, disassembled each section to manageable-sized components, and reassembled the units in the basement. Each fan included its own VFD, wired back to a custom panel for single point control.

When looking at the need for state-of-the-art precision humidification without using steam, the Condair (Nortec) DL system with custom RO skid was a perfect fit. The DL system is a hybrid atomizing/media style humidifier which relies exclusively on the advantages of both humidification methods of atomization and evaporation. This humidification system was therefore the first choice in terms of hygiene, energy efficiency, and cost-effectiveness. The atomizer nozzles’ low-pressure mode of operation translates into significant energy savings due to the lesser compression work, and the evaporator unit uses a patented ceramic evaporator which allows economical use of valuable humidifying water, ensuring hygienic operation. Because of the full-surface layout of the evaporation ceramics and the spray cone of the molecular atomizer nozzles, the overall Installed depth of the Condair (Nortec) DL inside the AHU cabinet could be reduced to up to 23.5 inches (600 mm), resulting in material savings on the AHU length when compared to some other atomizing/media technologies. The units required RO water, and Condair (Nortec) customized a skid-mounted unit using pumps, membranes, a storage tank, dechlorinator, and water softener for a complete system that also provided conductivity monitoring with BMS interface.

Tom Barrow Company was able to couple the two products together in a way that met the needs of both the University and the engineer on a project with challenges not unique to owners looking to update older equipment with state-of-the-art energy saving custom equipment.


Challenge: Replace old multizone Air Handling Units with VAV Air Handling Units and low energy humidifiers for tight humidity control.

Solution: Temtrol ITF model custom air handling units, using FANWALL Technology, and Condair (Nortec) model DL hybrid humidifiers with reverse osmosis skid.