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 …
Variable Speed Hydronic Pump Selection – Should I Specify the Largest Impeller?
We recently received an inquiry from an engineering firm deciding whether to change their pump schedule. They currently select the pumps at design capacity and …
Smart Variable Speed Centrifugal Pumps: Part 2 (Base Mounted)
Larger centrifugal pumps with horsepower over five are a great place to save energy in HVAC and plumbing systems. Historically, these larger pumps were typically …
Smart Variable Speed Centrifugal Pumps: Part 1 (Line Mounted)
This week and next we will talk about centrifugal pumps with the variable speed technology built into them. These pumps are called “Smart pumps.” Why …
B&G Systemwize: Overspeeding of Variable Speed Pumps
The term “overspeeding” in pump selection and operation is a topic of conversation in the world of hydronic design. When asked about this subject I …
How to Pick an HVAC Centrifugal Pump Part 9: Over Speeding HVAC Pumps & Motors
There are times when a little more capacity or a little more safety factor is needed from a pump selection. Often, we are asked about …
Variable Speed Pump Control: Wheels and Ladders and Diversity
Commercial and industrial hydronic heating and cooling systems will usually have variable speed distribution pumps. There are multiple ways to identify what speed the pumps …
Variable Speed Systems: Types of Sensors (Part 2)
Last week, in part one of this series, we looked at temperature, pressure, and differential pressure sensors to control the speed of a HVAC or …