Without working energy recovery wheels, the heating and cooling systems were forced to work overtime at increased cost to provide a comfortable indoor environment for the 2,000-plus concertgoers. The building’s service contractor, Cullen Mechanical, determined that the wheels were beyond repair and needed to be replaced.

Cullen’s engineers knew from past experience that simply replacing the wheels without solving the cleaning problem would invite the same undesirable maintenance situation. At House of Blues, airborne particles from the large crowds, special effects vapors, and confetti would continue to clog the new wheels if the energy transfer matrix could not be periodically maintained.

When selecting replacement wheels, Cullen prioritized both ease of installation and the ability to clean or replace the energy recovery matrix once the units were in operation. As they’ve done in the past, Cullen chose Airxchange Aftermarket replacement energy recovery wheels as the best solution moving forward.

Airxchange says it offers a wheel design that allows a single person to remove pie-shaped energy transfer segments with basic hand tools to be cleaned outside of the cabinet. The refresh-capability of Airxchange wheels means that they can be cleaned as often as the application dictates.

In contrast, the only cleaning or repair solution for the original wheels at House of Blues was to replace the entire wheel structure every five to six years, at great time and expense to the building owner.

After an onsite visit, an engineer from Airxchange presented Cullen Mechanical with a six- to eight-hour wheel replacement plan that minimized HVAC system downtime, ensuring that the two units would be operational for the start of that evening’s show.

Because of constraints of the air handler design, which blocked the removal or installation of fully assembled wheels, Cullen selected a replacement wheel kit from Airxchange that could be assembled within the cabinet of the AHUs.

Another reason for choosing the Airxchange replacement kit was that all of the components could be carried through the theater and up the stairs to the roof, avoiding the cost and complexity of having a police detail shut down the sidewalk on Boston’s busy Lansdowne Street in order to operate a crane.

The replacement wheels were fully assembled and tested at the factory before being partially dismantled to fit into the unique access points of the air handler. Once the old wheels were removed, the two Airxchange wheels were assembled inside of the cabinet in less than four hours.

Recognizing that entertainment venues often require more frequent cleanings than traditional HVAC comfort applications, Cullen took additional steps to reduce their client’s energy costs and potential HVAC system downtime. In addition to installing a fully-serviceable wheel, they also ordered a complete set of replacement segments for each unit. With a spare segment set on hand, operators can save time and maintenance costs by completely restoring the performance of any wheel in about 15 minutes. Once removed, dirty segments can be restored and prepared for the next cleaning cycle by soaking overnight in a cleaning solution.