Technician Head Trash
It’s Friday at 6 PM. The schedule is clear, as far as you can tell. Other guys have been getting cleared right and left, so you call in standby. Five minutes pass. Ten minutes pass. You check in again, and sure as &%$#, there it is! You get sent across town to another call that […]
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Why the New Guy Gets Fewer Callbacks
I was going through a recorded service meeting with the Kalos techs, and Bert shared something that has been rattling around in my head ever since. His team went digging through their callback data looking for patterns, and after stepping back and looking at it, one showed up that nobody expected: The newer techs were […]
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Why is 240V called “Single-Phase”?
Why is it called single-phase 240 when there are two opposing phases (or legs)? I wondered why we called two 120v opposing legs “single-phase 240” for years. Then someone pointed out to me that a typical “single-phase” pole transformer only has one power leg entering and two coming out. That freaked me out. How can […]
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Flowing Nitrogen? Make Sure You Purged First
Flowing nitrogen while brazing does not mean the air was cleared first. Learn how to purge large ACR piping, choose a practical regulator setup, and estimate time and cylinder use.
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What is a GFI?
First off, the correct acronym for a GFI (ground fault interrupter) is “GFCI” (ground fault circuit interrupter). The purpose is to act as a safety device to protect from electrical shock. GFCIs are important components of electrical safety; they even make an appearance in our electrical safety video. GFCIs can be built into outlets, circuit […]
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Laws of Energy and Matter
It’s always good to reaffirm some of the basics of energy, work, and matter. The five rules below are some of the most basic and important. The First Law of Thermodynamics States that energy cannot be created or destroyed. It can only change forms or be transferred from one object to another. If you’d like […]
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Condensate Switch Controversy
Condensate overflow prevention devices, or float switches, as they are often called, are such simple devices that you wouldn’t think there would be much room for controversy. In my experience, there are few areas of the trade where technician and installer preferences and opinions vary greatly. Let’s start with some float switch basics. Float (condensate) […]
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Does Mass or Volume Move Heat?
I once heard someone say, and I have since repeated many times, that BTUs ride on the back of cubic feet of air (CFM). As I’ve learned more, I’ve come to the conclusion that the weight or mass of the air passing over the evaporator coil is far more important to understand both in terms […]
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Avoiding and Eliminating Callbacks
Callbacks are horrible. They kill the trade from every possible angle. They destroy customer satisfaction and reduce technician morale by causing long hours, resulting in unprofitability for companies and overall less earning opportunity for everyone. Possibly worse of all, callbacks tell customers that you are no better than their cousin the maintenance man, or worse, […]
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