Author Archives: David Sellers

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

A New Commissioning Resource Website

For a while now, I have had this idea for a commissioning resource website floating around in the back of my head.  It seemed like there would be things that I could do with the way a website is organized … Continue reading

Posted in Resource List and other Resources | Leave a comment

Learning about Relay Logic; What’s a Relay?

Author’s Note:  I edited this to put in pictures with better contrast for the relay images further down the post and for some reason, instead of just replacing the original post, the system put it up as a new post.   … Continue reading

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The Other Side of Life

I really enjoy working on this blog because the technical things I discuss are of interest to me and by sharing what I know, I am sharing what my mentors have shared with me, sort of playing it forward I … Continue reading

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Hourly Weather Data Website Update

Frequently, when operating buildings or doing energy calculations for their systems, it is very handy to be able to obtain hourly weather data for a given location.   That is why I think the post I did a while back on … Continue reading

Posted in Weather and Climate Interactions with Buildings and Systems, Weather and Climate Resources | Leave a comment

Control System Fundamentals

This post evolved to support a string of posts I will start next to support an exercise in one of the classes I am involved with at the Pacific Energy Center.  In those posts, we will look at how you … Continue reading

Posted in Controls, HVAC Fundamentals, Operations and Maintenance, Pneumatic Controls | 2 Comments

Happy Holidays, 2017; Recollections of George Hinke

For the past couple of years, around this time of year, I have tried my hand at writing a non-technical thing that has some measure of seasonal appropriateness, like the post last year about snow crystals.  So, this post is … Continue reading

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