Challenge

A public sector higher education client in the Illinois Capital Development Board portfolio had various air handling units (AHUs) that were original to the building and beyond their anticipated service life. The client needed to replace these units because they were experiencing operational issues and were no longer reliable. Additionally, they were noisy, suffered from capacity reductions, and, in some cases, used double the amount of outside air than permitted by current code requirements.

Solution

Valdes reviewed the current state of the AHUs and prepared design documents and specifications to order new systems to replace them. The new units will be much quieter, will operate as single-zone or multi-zone VAV with supply air temperature reset and will modulate the outside air based on required code minimum quantities. Free-cooling economizer controls will be much more reliable and will control based on comparative enthalpy to maintain space humidity set points.

Impact

The new units have a more efficient design and utilize half the motor horsepower. This will take stress off the cooling tower which is also beyond its useable life and experiencing decay. Once the new AHUs are installed, occupants on the client’s campus will experience higher levels of indoor environmental quality and the client will be able save on their utility costs.

Services

Mechanical

Electrical