Parallel Pumping Sketch
Parallel Pumping Sketch

Parallel Pumping: 2-Position Control Valves on Multiple Cooling Towers (Part 5)

RL DeppmannHydronic System Design, Selection and Specification, Cooling Towers, Piping and Pumps, Parallel Pumping, Parallel Pumping, Monday Morning Minutes, Commissioning and Balance, Cooling Towers, Pumps

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 …

Small Drawing of Header Supply and Return
Small Drawing of Header Supply and Return

Parallel Pumping with Unequal Condensers (Part 4)

RL DeppmannCooling Towers, Piping and Pumps, Parallel Pumping, Parallel Pumping, Monday Morning Minutes, Commissioning and Balance, Cooling Towers, Pumps, Hydronic System Design, Selection and Specification

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 …

Griswold Wafer
Griswold Wafer

Parallel Pumps in Condenser Applications: Limiting the Flow Rate (Part 2)

RL DeppmannParallel Pumping, Monday Morning Minutes, Commissioning and Balance, Cooling Towers, Pumps, Hydronic System Design, Selection and Specification, Cooling Towers, Piping and Pumps, Parallel Pumping

In part 1 of this series we offered an example condenser water pumping system. The design of this example is 800 GPM per condenser for …

Where Cavitation Begins – Cooling Tower Pumps and Piping

Norm HallCooling Towers, Hydronic System Design, Cooling Towers, Piping and Pumps, Monday Morning Minutes, Cooling, Cooling Towers, Pumps

Last week the R. L. Deppmann Monday Morning Minute defined NPSHR, and ended with the Hydraulic Institute (HI) definition as the absolute pressure that will cause the total head of the pump to be reduced by 3%, due to flow blockage from cavitation”. Of importance is the fact that it does not say that NPSHR is where cavitation begins.

Differences in Compression Tank and Expansion Tank Formula – Part 9

Norm HallHydronic System Design, Expansion and Compression Tanks, Expansion/Compression Tanks, Monday Morning Minutes, Tanks

Now we understand the difference between expansion and compression tanks as described in the R. L. Deppmann Monday Morning Minutes of 1-9-12 and 1-16-12. What happens to the formula results when comparing these two types of tanks? In part 1 of this series, we introduced the formula for tank sizing. The denominator of the equation was: (Pa /Pf) – (Pa /Po)