Most heating and cooling pumps in commercial buildings operate in a variable speed mode. Today, we take your Monday Morning Minutes to explore the variable …
Three-way and Two-way Control Valve Basics in Hydronic Systems
Centrifugal pumps operate at the intersection of the pump curve and the system curve. Last week we developed the system curve for an example closed …
Closed System Curves in HVAC Hydronic Systems
A system curve is a graphical representation of how a heating or cooling system flow rate and system head might change as the load …
What’s On a Pump Curve?
Selecting centrifugal pumps for heating, cooling, process, and plumbing systems is easy once you understand how they work and what you are seeing when …
Centrifugal Pumps: How Do They Work?
How a centrifugal pump moves water may seem too basic for engineers and contractors to spend time reading about. However, understanding how a centrifugal pump …
Ion Exchange Water Softener Packaged Solution
There are times when a commercial ion exchange water softener is the preferred solution for hard water in potable water systems. The map above is …
Minimum Chilled Water Flow Rates – Variable Primary Systems
I have written a great deal about the minimum flow rate requirement in centrifugal pumps. We recently received an email from an engineer who was …
Variable Frequency Drives (VFD) and Single-Phase Power
As a representative for Danfoss VLT variable frequency drives (VFD), we often are asked about the use of the VFD when single-phase power is the …
Centrifugal Pumps: Determining Flow Rate Using Amp Readings
We understand that the best way to determine the flow rate of an operating pump is the proper readout of gauges attached to the pump …
Hydronic Systems Pump Minimum Flow Methods
Minimum pump flow rate is critical to the trouble-free operation and longevity of the centrifugal pump. In the last blog we described the use of …