Avoiding Common Chilled Water Distribution Problems | P2S Inc.
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Vice President & COO

Kent Peterson

PE, ASHRAE Presidential Fellow, LEED AP BD+C, BEAP, MCIBSE

Avoiding Common Chilled Water Distribution Problems

ASHRAE Journal, June 2015

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    The design decisions made in selecting and sizing chilled water distribution system components have a direct impact on the performance of the overall chilled water system. Attention to fundamentals can also help improve system performance.

    This month, I intend to point out some common problems that must be addressed in chilled water distribution systems. These problems can impede the system’s ability to perform reliably and efficiently. These are all real examples from actual facilities that I have designed, peer reviews I performed of designs by others, or retrofits of systems designed by others.

    Distribution System Objectives

    It is important to begin with some key objectives of the chilled water distribution system. These objectives should be viewed on an annual basis and not simply at design conditions. The system should:
    • Deliver the amount of chilled water required to satisfy the loads;
    • Operate reliably;
    • Minimize pumping energy;
    • Minimize excessive pressure differential across the supply-return distribution system; and
    • Optimize life-cycle costs of distribution system components.

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Scripps CCB (Done) (2013-6973)


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P2S provided Mechanical, Electrical, and Plumbing engineering design for the two-story Critical Care Building (CCB) with a new Central Utility Plant and emergency airlift helipad. The CCB consists of a new emergency department, procedure rooms, and med-surge patient beds. Because the hospital was so focused on preparing for future development, the design called for constant reassessment and forward-thinking about the needs of the hospital community in the next 50-100 years.

Scripps CCB (Done) (2013-6973)


Bold Text:Regular Text (For Specs)
Bold Text:Regular Text
Bold Text:Regular Text
Bold Text:Regular Text

P2S provided Mechanical, Electrical, and Plumbing engineering design for the two-story Critical Care Building (CCB) with a new Central Utility Plant and emergency airlift helipad. The CCB consists of a new emergency department, procedure rooms, and med-surge patient beds. Because the hospital was so focused on preparing for future development, the design called for constant reassessment and forward-thinking about the needs of the hospital community in the next 50-100 years.