Category Archives: Air Handling Systems

These posts focus on retrocommissioning findings for air handling systems

Howden North America’s Fan Engineering Handbook

Authors Note:  So, some good news on this.  For a while, some of the links below did not work and I could not get information back from Howden regarding how to get a copy of the handbook since my contacts … Continue reading

Posted in Air Handling Systems, Resource List and other Resources | 2 Comments

A Free Electronic Psych Chart and How to Use It to Plot Basic HVAC Processes

Ryan Stroupe of the Pacific Energy Center recently worked out a deal that allows him to provide a free limited capability version of Hands Down Software’s electronic psych chart.  You can get a copy at this link and a overview … Continue reading

Posted in Air Handling Systems, Economizers, Excel Techniques, HVAC Calculations, HVAC Fundamentals, Psychrometrics, Resource List and other Resources, Weather and Climate Interactions with Buildings and Systems | Leave a comment

Economizers–The Physics of Linkage Systems

In the post before the previous, I was discussing an economizer performance problem in a facility we worked with as a class in Monterey California.  One of the problems was related to the mechanics of motion in the linkage system … Continue reading

Posted in Air Handling Systems, Controls, Economizers, Pneumatic Controls | Leave a comment

Economizers–The Physics of a Mixed Air Plenum

I’ve been working on a post that shows how a scatter plot technique can be used to assess the performance of an HVAC airside economizer.  It’s based on comparing a plot of outdoor air temperature vs. mixed air temperature for … Continue reading

Posted in Air Handling Systems, Controls, Economizers, HVAC Calculations, HVAC Fundamentals, Psychrometrics | Leave a comment

Retrocommissioning Findings: Scoping a Dental Clinic VAV Reheat System–Part 1

I’m currently involved with a number of field oriented classes in which the instructors mentor the students through a retrocommissioning process on a system in an existing building in real time.  Based on past experience with this process, I have … Continue reading

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System Effect–Dealing with the Point Where the Fan Meets the Duct

I am going to take a break from my string on building a psych chart to do a post on System Effect in support of one of the classes Ryan Stroupe and I teach at the Pacific Energy Center.   If … Continue reading

Posted in Air Handling Systems | 1 Comment

Retrocommissioning Findings: Economizer Mixed Air Plenum Stratification–Overview

Happy New Year! I hope everyone had a nice holiday and now are getting back into the swing of things.  Kathy and I had a great holiday and are just finishing putting away the Christmas decorations, which always seems to … Continue reading

Posted in Air Handling Systems, Economizers, Retrocommissioning Findings, Weather and Climate Interactions with Buildings and Systems | 2 Comments