Create a New Variable Speed Pump Control Curve after Hydronic Balancing
This week, the R. L. Deppmann Monday Morning Minutes will explain how to show multiple speeds on a pump curve and how to determine what …
Hydronic Pump Balance using the Variable Speed Drive (VFD) with No Balance Valve on Pump
When there is no hydronic pump discharge balance valve, the variable frequency drive (VFD) is an important part of the balance procedure. How does the …
Hydronic Pump Balance using the Variable Speed Drive (VFD) with Assistance from a Triple Duty Valve
Most centrifugal pumps in heating and cooling systems have some oversizing in the head calculation. Once the HVAC hydronic system is proportionally balanced per ASHRAE …
Process System Pump Selection: Controls to Reduce Maintenance Time
In the last R. L. Deppmann Monday Morning Minutes I defined the difference between flat curves and steep curves in a hydronic pump selection. I …
Variable Speed Pump Control – More Detailed Curve and Area Control
Curve control, Area control, Sensorless control, Remote DP sensor control. Local sensor control: the shopping cart of speed pump controls can get overwhelming. We just …
Hydronic Pump Energy: Motor & VFD Efficiency – How Low Can You Go?
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 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 …
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 Control & Automatic Balance Valves (Part 4)
A few weeks ago in the R. L. Deppmann Monday Morning Minutes (MMM) part 3 of this series, we showed that direct return systems with …