I’m in the middle of the series of blogs on parallel pumping. We can’t ignore the efficiency of variable frequency drives and motors when looking …
HVAC Hydronic System Variable Speed Pump Operation
I am beginning a series on parallel staged variable speed (VS) pumps. As I write this series, it is important to understand and refer to …
HVAC Hydronic Pumps – Should I Trim the Impeller or Trim with Speed? (Part 2 of 2)
In the last R. L. Deppmann Monday Morning Minutes, I offered a couple of reasons why an engineer would schedule a larger impeller than needed …
HVAC Hydronic Pumps – Should I Trim the Impeller or Trim with Speed? (Part 1 of 2)
Engineers schedule a pump capacity in GPM and head along with the horsepower. The pump manufacturer traditionally trims the impeller from the maximum size, also …
Department of Energy Pump Standards [Part 5] – Your Choice of Variable Frequency Drive
My March 11th blog article concerning The Department of Energy Standards for centrifugal pumps raised questions about the engineer’s or owner’s choice of variable frequency …
Over-Speeding of B&G Variable Speed Pumps
I hope everyone had a wonderful Thanksgiving celebration. Here at Deppmann, we are thankful for the great industry we serve and the great people who …
Variable Speed Pump Area Control & System Diversity: Part 3
In the R. L. Deppmann Monday Morning Minutes part 1 of this series we defined diversity in hydronic systems. Part 2 introduced the sensorless pump speed …
HVAC Variable Speed Pump Curve Control: Part 2
The HVAC engineer or designer has many choices when it comes to the control of variable speed pumps. The traditional differential pressure (DP) transmitter near …
HVAC Variable Speed Pump Control System Diversity: Part 1
HVAC variable speed pump control does not have to be complicated. Often times a simple differential pressure sensor (DP) at the farthest point from the …
Bell & Gossett Brings Independence to Pump Selection with ESP-Systemwize
Photo by Radiant Shutters on Flickr On July 2, 1776, General Howe landed his fleet in New York and unloaded the first wave of 19,000 …