Moving past a 100-year-old solution
For over 100 years, base-mounted end-suction pumps have been the standard for HVAC pumping systems. However, Grundfos is challenging the conventional wisdom by engineering, designing and providing high efficiency packaged pumping solutions. Grundfos packaged Multi E and Hydro MPC systems improve on traditional solutions by saving space, reducing the cost of ownership/maintenance and increasing pump efficiency and functionality.
Applying the Grundfos Hydro MPC skids for the client’s new headquarters was a great solution, but it meant rethinking the justifications and benefits of applying base mounted end suction pumps. The contractor, design team and client weren’t ready to dismiss this approach without validating the Grundfos solution.
A Different Approach
Investigating the potential of an innovative design
The McCotter Energy team provided an up-front energy analysis comparing standard end suction pumping methods to the innovative Hydro MPC design, and provided data to the consulting engineer for independent verification.
The specific recommendation for the hot water and chilled water pumping systems was the Grundfos Hydro MPC, a pump skid system with parallel vertical multistage pumps and intelligent controls. The advanced Grundfos Hydro MPC controller continuously calculates the optimal combined efficiency for the pump array, controlling and cascading the pumps accordingly to match the variable heating/cooling load.
Compared to end suction pumps with variable frequency drives (VFD), the Hydro MPC has superior turn down and wire-to-water efficiency. When operating at minimum speed (30 Hz) end suction pumps still often require flow bypass to keep them from cavitating. The 10:1 turndown of the Hydro MPC eliminates the requirement and operational costs associated with bypassing flow.
Results & Successes
Leading the industry
After careful consideration, investigation and analysis the client, design team, and contractor selected the Grundfos Hydro MPC for the project. McCotter Energy Systems provided the systems on-time and on-budget.
Equipment installed included:
4-Pump Grundfos Hydro MPC skid for the heating loop
5-Pump Grundfos Hydro MPC skid for the cooling loop with two blanked-off connections for future cooling expansion