In our last blog, we showed you what happens in a variable speed system when load drops. For clarity, we chose an unrealistically simple example of a system with only one coil. Today we’re going to give our system a small dose of reality by incorporating multiple zones...Read More
When looking at Bell & Gossett pump selections we often find higher part load efficiency (PLEV) pump choices are to the right of BEP or best efficiency point. How close to end of curve should a prudent engineer choose?Read More
Although the DOE’s new pump efficiency standards raise the bar for manufacturers to build more efficient pumps, its rating system should not be looked at as a shortcut to efficient pump selection. Careful consideration of part load efficiencies applied to realistic load profiles is still the only way ...Read More
It should be clear by now that selecting a pump based on design conditions and best efficiency point (BEP) will not yield optimum system efficiency. We’ve also learned that virtually every HVAC pump system will have a minimum amount of pump head, even in the absence of demand. In between these minimum and maximum operating conditions lies the control range for our pump. Keeping all this in mind, how do we select the most efficient pump for a specific application?Read More
By Chris Edmondson
Now that we know what happens when we vary flows and mix temperatures in a primary secondary pumping system, let’s explore these theories in some more realistic scenarios.
As discussed in a previous blogs, when it comes to primary secondary systems, one of three flow patterns is always in occurrence:Read More