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 …
Pump Minimum Flow Using a Cla-Val Back Pressure Valve
Minimum pump flow rate is critical to the trouble-free operation and longevity of the centrifugal pump. The pressure sustaining valve or back pressure valve is …
Pumping From an Atmospheric Tank: Pump and Tank Control (Part 3)
Let me start by wishing everyone a Happy and Prosperous New Year. This blog begins the 14th year of the R. L. Deppmann Monday Morning …
Pumping from an Atmospheric Tank: Pump and Tank Piping (Part 2)
What can be simpler than pumping water from an open or atmospheric tank into another tank or system? What seems simple to many opens a …
Pumping from an Atmospheric Tank: Pump Selection and Installation (Part 1)
What can be simpler than pumping water from an open or atmospheric tank into another tank or system? What seems simple to many opens a …
Sump and Sewage Pump Flow Rate & Minimum Run Time
The minimum run time in a sump, effluent, or sewage pump is determined by the flow rate and the volume of water in the basin …
Glycol Pressure Drop Corrections for Hydronic Systems (Part 2)
Last week the article covered pressure drop correction calculations. Today we offer you some handy charts to use for second glycol correction pressure drop. Example: I have calculated the water piping pressure drop through a chilled water system to be 80 feet using the System Syzer. Question: What is the pressure drop if I have 50% Ethylene Glycol/Water with temperatures of 45°F to 55°F? Answer: The average temperature is 50°F, so my factor is 1.47. [Read more…]