Condensing Boiler Plant Piping Design & Control Part 2: Variable Primary Flow Systems

There are basically two ways to incorporate variable flow into a condensing boiler system. You can have just one set of primary pumps, which vary flow through the entire system from boilers to coils, or you can have both primary and secondary pumps, which vary flow through their respective loops. In this blog, we’ll address the former....
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Condensing Boiler Plant Piping Design & Control Part 1: Setpoint Control Sensor Location

Where should the boiler set point control sensor be located in a condensing boiler system? Given the fact that we (hopefully) know that the return water to a natural gas-fired condensing boiler should be 120°F or below in order for the boiler to condense, simple logic may lead you to believe that you should control based on the return water temperature...
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Understanding Primary Secondary Pumping Part 5: Best Practices for Piping

By Chris Edmondson

Piping in a primary secondary pumping systems as a whole can be quite complex, but when it comes to the “primary” part of the system, there are really only two approaches:  Dedicated or Non-dedicated.

Figure 1 shows the chillers in a primary secondary system piped with one pump per chiller.  If the chillers

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Understanding Primary Secondary Pumping Part 1: Behold the Humble Tee!

Are you involved in the design or installation of hydronic systems?  Do you anticipate becoming involved?

 If you answered yes to either of these questions, this blog series on primary/secondary pumping will interest you.  If you are a hydronic’s veteran, feel free to skip the first few blogs in the series – they may be too much of a review.  Better yet, pass them onto a junior associate and

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Designing Waterside Economizer Piping to Meet ASHRAE 90.1 - 2010

By Chris Edmondson 

Gone are the days of optional air or waterside economizing.  Gone also are the days of waterside economizers piped in parallel.  In other words, the “either/or” operation of the chillers and economizers that we’re all accustomed to will soon be a thing of the past.

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