Giving Thanks for the Hard Stuff
Trigger Warning: This article isn't specifically about air conditioning, and it includes a markedly Christian worldview. If you would prefer that I  “stick with the A/C stuff, preacher boy,” then this is one you should skip—or not 🙂  Also, it's my birthday this week, so give me a pass.  Today, families all across the country […]
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Old Books
I've always liked old books. Think about an old printing press somewhere in Chicago or Boston or Scranton, Pennsylvania. Imagine workers with their hands covered in ink up to their elbows, setting type while giant machines of iron, steel, and brass stamp out a book page by page. Then those pages go on to be […]
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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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Leaking (Bypassing) Valves
We had a class with our refrigeration techs, and the topic of leaking and bypassing service “angle” valves and ball valves came up. One of the techs pointed out that most valves recommend loosening the top nut on ball valves and the packing nut on angle valves before turning the stem for maximum longevity of […]
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What is the “Mid Point” of a Refrigerant Blend?
As we have mentioned in several previous articles (such as this one HERE), many blended refrigerants have glide, which simply means they boil and condense over a range of temperatures instead of just one temperature. As an example, consider refrigerant R407c. It is a zeotropic blend, which means it has enough glide to make a […]
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Maintenance During Major Repairs
  Every contractor is different. I get that. We don't all need to do everything the same way or include the same services with repairs, but there are some “best practices” that can save you a lot of heartache before, during, and after you make a big repair. Catch it During Diagnosis Let's say you […]
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W1, W2, & E
I got this question via email (edited slightly for length): Some things I've done because I've been taught to do them yet I don't know why I do them. One of those things is putting a jumper between w1/e and w2. Sometimes, in the case of a Goodman for example, I've been taught to combine […]
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Don’t Forget the Service Wrench
One of my most popular YouTube videos goes over how to adjust TXV superheat. It's a very simple little video that I did at my desk, and the other day I got this comment: “Good Video but I hate to say this BUT, with the title SCHOOL, why would you show the public an instructional […]
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That Rusty Coil/Galvanic Corrosion
How many times have you looked at the bottom right-hand side of an evaporator coil and seen all sorts of rust, even on a fairly new coil? You may have noticed that many evaporator coils and even some condenser coils will start to corrode where the galvanized steel endplates touch the copper u-bends of the […]
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