How to Read a Pump Curve - Part 3

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 Pump selection can have dramatic impact on the overall operating cost of a hydronic system.  Consulting several pumps curves prior to the selection of a pump is the key to minimizing these operating costs.   In this blog we will discuss the factors that impact pump efficiency and how pump curves can be used to take the guesswork out of efficienct pump selection. 
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How To Read A Pump Curve - Part 2

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One of the most important lines on a pump performance curve is the Net Positive Suction Head (NPSH) curve.  Discreetly applied either below or above the pump performance and efficiency curves, this single plotted line is the key to avoiding cavitation. Required NPSH or NPSHR for a given pump increases with flow.  So, using the pump curve shown in Figure 1, we can see that the NPSHR for this Model 1510 B & G pump with a 8” impeller and 800 GPM and 33 Feet of Total Head is 12 feet of head. 
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How To Read A Pump Curve – Part 1

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If a picture is worth a thousand words then a pump curve must be worth several thousand.

 Make no mistake, there’s a lot of information on a centrifugal pump curve like the one shown here.  It’s no wonder that many newly practicing engineers are a little intimated by them.

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NPSH Demystified: What Is It and Why Is IT So Critical?

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NPSH.  We know what it stands for—Net Positive Suction Head--but do we really know what it means?  Or why it’s so important?  More often than not, explanations of NPSH begin with confusing terminology and (even worse) confusing equations.  That’s not a good starting point.  The concept of NPSH is.
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Designing Waterside Economizer Piping to Meet ASHRAE 90.1 - 2010

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By Chris Edmondson 

Gone are the days of optional air or waterside economizing.  Gone also are the days of waterside economizers piped in parallel.  In other words, the “either/or” operation of the chillers and economizers that we’re all accustomed to will soon be a thing of the past.

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