Selecting centrifugal pumps for heating, cooling, process, and plumbing systems is easy once you understand how they work and what you are seeing when …
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 …
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…]
Pressure Drop Corrections for Glycol in HVAC Systems (Part 1)
Question: I have selected my piping friction loss based on water, but I am pumping a glycol solution. What correction do I use? Answer: There are three glycol corrections when designing a hydronic or process cooling system; heat transfer correction, pressure drop correction, and pump curve correction. This R L Deppmann Monday Morning Minute defines the second of three glycol corrections. [Read more…]
Circulator Pump Curves & Step Sized Selections. A Domestic Water Recirculation Example
Circulator series pumps are those small inline pumps that have fixed impeller choices with no impeller trimming available. When these pumps have ECM technology, the …
How to Limit the Speed of the Pump using a Danfoss Variable Frequency Drive
In this Service Tip of the Month, we demonstrate how to limit the speed of the pump using the Danfoss Variable Frequency Drive (VFD).
Hydronic System Pump Selection: Flat vs. Steep Curves
An engineer in Michigan called about a large project with several pumps being selected in parallel for a plant chilled water system. He commented that …
HVAC Hydronic System: Parallel Pumping Specifications
OK. I get it! Parallel pumping is a design technique I should review on most of my projects where first cost and energy cost are …
The Department of Energy (DOE) Pump Standards – Now is the Time to Choose
The Department of Energy (DOE) pump standards goes into effect on January 27, 2020. This affects projects you are sending out to bid right now! …