Modern Pump Selection Part 3: Impact of Constant Fixed Head On Pump BEP

Modern Pump Selection Part 3: Impact of Constant Fixed Head On Pump BEP

In our last blog we explained why in real life HVAC applications, variable speed pumps almost never operate at zero speed.  Even at no flow, the impeller must be spinning enough to produce some amount of pressure at the 2-way valve in order to quickly establish full flow at the critical circuit IF demand suddenly occurs. Here's a silly way to think about it....

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Modern Pump Selection Part 2: Theory Vs. Real World Operation of Variable Flow Pumping

Modern Pump Selection Part 2:  Theory Vs. Real World Operation of Variable Flow Pumping

In variable speed pumping systems, does zero load ever result zero pump speed?

Practically speaking, the answer is no.  In closed hydronic systems with 2-way valves there is almost always some amount of differential pressure created by continuous impeller rotation – even when....

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Solving Balance Issues with A Differential Pressure Controller

Solving Balance Issues with A Differential Pressure Controller

What are your options when unbalanced circuits in an existing hydronic system are creating comfort issues due to underflow or overflow through coils?  We just spent the last twelve blogs describing the various methods for balancing a start-up system but do those same methods apply to existing systems and retrofits? 

The short answer is....

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Hydronic Balancing Part 2: Making the Most of System Diversity

Practically any commercial or institutional building has a certain amount of diversity within its cooling load, meaning that peak loads will never occur simultaneously in all sections or zones of a facility. By mapping out the individual load patterns of these sections, engineers can adjust the mechanical design to reduce the overall amount of installed cooling capacity. This means incorporating variable flow, which necessitates precise hydronic balancing.
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Cooling Tower and Condenser Water Design Part 11: Avoiding Common Pitfalls

We thought it would be a good idea to review some of the most common pitfalls in cooling tower/condenser water design and how to avoid them. We see these so often and the consequences can be so profound that each bears a final warning. Take care to avoid these scenarios and we promise that everyone (from your equipment suppliers to your chemical treatment specialist) will be much happier.
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