The Challenge
After careful review, Parkland College understood that the existing HVAC mechanical and control systems would not allow them to achieve their sustainability and energy reduction goals. The system’s components were no longer produced or supported by the manufacturer and access to replacement parts and refurbished controllers was extremely limited. In addition, the air handling unit chilled water control valves were system-dependent type valves that were not maintaining consistent flow.
The Process
A phased approach addressing mechanical and control issues was mutually agreed upon. Ruyle Mechanical Services/ECSI developed a prioritized list of proposals adhering to Parkland College’s sustainability and energy efficiency goals. The solutions were based on the current energy efficiency codes and standards.
The Result
The College's Automated Logic (ALC) WebCTRL system provides detailed scheduling of occupied/unoccupied times for the HVAC equipment during which the spaces’ temperatures can be set back for optimum energy efficiency. The expansion of the WebCTRL system to the 120 VAV boxes provides reset type control of the hot water reheat control valves and the volume dampers. This controls the temperature and volume of the air supplied by the VAV boxes to within the guidelines of the current energy efficiency codes and standards and maintain acceptable comfort levels in the building. The installation of system-independent chilled water control valves will result in precise flow of chilled water to the main air handlers’ coils during fluctuations of the campus chilled water loop’s pressure as the cooling demand increases and decreases.
