The Pump Affinity Laws are used to determine the system curve. If we know the point of operation on a pump curve, we can determine …
The Bell and Gossett System Syzer and Pump Affinity Laws
Hydronic heating system flow rates and pressure drops are related through a series of AFFINITY LAWS. Let’s examine the laws and how to use them …
Variable Frequency Drives (VFD) and Single-Phase Power
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).
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: 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 …
Hydronic Pump Piping and Trim: Vibration Inertia Bases
Oftentimes an engineer will specify a pump mounted on springs, vibration base, inertia base, or isolation base. Our industry tends to use a number of terms for the same …
Using ECM Smart Circulator Pumps in Primary Pump Applications in Hydronic Systems
Last week I featured the ECM High-Efficiency Smart Circulator Pump used in a secondary application. This week the R.L. Deppmann Monday Morning Minutes continues to …
Smart ECM Pump Applications – Variable Speed Heating & Cooling System
ECM (Electronically Commutated Motor) pumps have electronics built into them which may be used to vary the speed of the pump. If the pump manufacturer …










