Converting From Primary/Secondary to All-Variable Flow

Avery, Gil
July 2009
Heating/Piping/Air Conditioning Engineering;Jul2009, Vol. 81 Issue 7, p26
The article offers tips on how to convert primary/secondary chilled-water systems to all-variable flow. It indicates the need to replace the air-handling-unit (AHU) three-way valves and two-way modulating valves which have not been closed tight. It suggests removing the balancing valves that are not serving as isolation or service valves. It also recommends making specifications for equipment interlocks, chiller-isolation-valve, and condenser-water controls.


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