Category Archives: Retrocommissioning Findings

These posts follow various retrocommissioning findings from discovery through implementation, verification and persistence.

A Control Logic Exercise and a Way to Get Comfortable With Navigating SketchUp Models

As many of you know, I have been experimenting with using SketchUp models as a way to teach EBCx techniques.  I frequently use them in my classes and also have started to post self-study exercises that are based on the … Continue reading

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Cooling Tower Flow Distribution and Variable Flow in Condenser Water Systems

One of my current obsessions is how subtle details regarding how you pipe a cooling tower can make a huge difference in how the flow is distributed.  I’ve been interested in that for a long time actually as the result … Continue reading

Posted in Condenser Water Systems, HVAC Fundamentals, Operations and Maintenance, Retrocommissioning Findings | Leave a comment

An Existing Building Commissioning Learning Opportunity

The picture above is a panorama I shot earlier this year in a recently renovated central chilled water plant serving a large high-rise office building in down town San Francisco. The people in the picture are students in the Existing … Continue reading

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The Persistence of the Benefits of Commissioning (Plus a Few Pictures of Legacy Instruments)

As you probably have noticed if you follow the blog, I love finding old instruments in my travels. I have even been lucky enough to save a few of them from the dumpster, like this resonant frequency-based tachometer …   … Continue reading

Posted in Controls, Mentoring and Teaching, Operations and Maintenance, Pneumatic Controls, Retrocommissioning Findings | Leave a comment

Resources for the Resourceful – Utility Analysis Spreadsheet Tool

Authors Note: Since the point in time when I published this post, some of the links have expired. So, I have gone through it and renewed them and also made a few edits. Linking to the Weather Data Depot in … Continue reading

Posted in Excel Techniques, HVAC Calculations, Operations and Maintenance, Resource List and other Resources, Retrocommissioning Findings | Leave a comment

Pneumatic Controls Resources

Author’s Note: I originally published this post on March 3, 2013.  At that time, all of the resources I mention below were loaded up in “the cloud” on a Google Drive.  Since that time, I have created the commissioning resources … Continue reading

Posted in Operations and Maintenance, Pneumatic Controls, Resource List and other Resources, Retrocommissioning Findings | Leave a comment

Condenser Water Systems, Air Entrainment, and Pump Cavitation

This post is the result of a discussion I was having as the result of a comment made on a previous post about commissioning a condenser water system.  The initial question was to ask if the solution I had suggested … Continue reading

Posted in Chillers and Chilled Water Systems, Operations and Maintenance, Retrocommissioning Findings, System Diagrams | Tagged , , | Leave a comment

Retrocommissioning Findings: Reducing Boiler Purge Cycle Losses–How I Obtained My Results

This post expands on what I did in the final section of the last post to show how I arrived at the answers I arrived at. Before proceeding, I want to emphasize that what I am about to show is … Continue reading

Posted in Boilers, Hot Water Systems, and Steam Systems, Data Logging, Excel Techniques, HVAC Calculations, Retrocommissioning Findings | Leave a comment

Retrocommissioning Findings: Reducing Boiler Purge Cycle Losses

Greetings after another break in the action in terms of my posting rate.  As those of you who follow this blog know, sometimes, I get pretty busy and since writing this is not exactly my “day job’, my posting rate … Continue reading

Posted in Data Logging, Excel Techniques, HVAC Calculations, HVAC Fundamentals, Operations and Maintenance, Retrocommissioning Findings | Leave a comment

Aliasing and Other Factors Affecting the Accuracy of Field Data

One of the challenges we face when we work with building systems is capturing enough sufficiently accurate data to paint a true picture of what is going on.  This is harder than it sounds for a number of reasons, including … Continue reading

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