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 only …
How to Limit the Speed of the Pump Using a Danfoss Variable Frequency Drive
In this Monday Morning Minute, we demonstrate how to limit the speed of the pump using the Danfoss Variable Frequency Drive (VFD).
Adjusting a Variable Frequency Drive (VFD) to Over Speed a HVAC Centrifugal Pump
In past R. L. Deppmann Monday Morning Minutes, we discussed the option of a small amount of over speeding on B&G pumps in HVAC applications. …
Parallel Pumping: 2-Position Control Valves on Multiple Cooling Towers
Over the last few weeks the Monday Morning Minutes posts have looked at pumping issues with multiple condensers and pumps. One of our most-received questions …
Parallel Pumping in Condenser Applications: Automatic Differential Pressure Control (Part 3)
Chilled water condensers are normally operated as constant-flow devices and the pumps serving them are constant-speed. Why would you ever use a variable-speed drive for …
Parallel Pumping in Condenser Applications: Limiting the Flow Rate (Part 2)
In part 1 of this series we offered an example condenser water pumping system. The design of this example is 800 GPM per condenser for a …
Parallel Pumping in Condenser Applications (Part 1)
Applying a single constant-speed pump for each condenser in a chilled water application is a normal design for the HVAC engineer. The chiller manufacturers suggest …
5 Effective Cooling Tower Treatment and Monitoring Strategies
In this fourth and final installment of our series on In August 2025, Essential Water Quality Management to Safeguard Health and Infrastructure, we will explore …
Protecting Your HVAC Operating Equipment Assets Requires Proper Water Quality Management
In this third installment of our series on Essential Water Quality Management to Safeguard Health and Infrastructure, we will discuss the importance of water …
5 Effective Cooling Tower Treatment and Monitoring Strategies
In August 2025, Central Harlem faced a serious public health crisis when an outbreak of Legionnaires’ disease sickened over 100 individuals and claimed seven lives. …