The Hydraulic Institute (HI) is a global authority on pumps and pumping systems. Think of them as the ASHRAE of pump design and testing. HI, …
Net Positive Suction Head (NPSH) Part 1 of 5 – Terms and Definitions
One of the most misunderstood concepts in pump selection for hydronic design is the net positive suction head or NPSH. Problems with NPSH can spell …
Energy Savings Using Variable Speed Water Pumps on Constant Flow Condensers
When using multiple parallel condensers with constant speed pumps, the flow rate at part load may be excessive and problematic. Our last blog on this …
Multiple Condenser Cooling Tower Pumps – “Solutions for Excessive Flow”
The design and flow balance in systems with multiple parallel condensers is straight forward. We should expect no issues at full capacity. What happens when …
Balancing Constant Speed Cooling Tower Pumps with Multiple Condensers
It is important to check the single pump operation when balancing parallel pumps for multiple constant speed cooling tower pumps. The condensers and pumps are …
Selecting Constant Speed Cooling Tower Pumps & Balance Valves with Multiple Condensers
It is important to check the single pump operation when selecting parallel pumps for multiple constant speed cooling tower pumps. In the last R. L. …
Constant Flow Cooling Tower Pumps & Variable Frequency Drives (VFD)
The blistering hot weather here in southeast Michigan caused me to turn my attention to cooling tower pumps and their control. Cooling tower pump control …
Parallel Pumping: 2-Position Control Valves on Multiple Cooling Towers (Part 5)
Over the last few weeks the Monday Morning Minutes posts have looked at pumping issues with multiple condensers and pumps. One of our most-received questions …
Parallel Pumping with Unequal Condensers (Part 4)
Over the last few weeks our Monday Morning Minutes posts have looked at pumping issues with parallel, equal-sized condensers and pumps. This week we will look …
Parallel Pumping in Condenser Applications: Automatic Differential Pressure Control (Part 3)
Chilled water condensers are normally operated as constant-flow devices and the pumps serving them are constant-speed. Why would you ever use a variable-speed drive for …