It Has a Flat For a Reason
When tightening down a blower wheel or a fan blade on a motor shaft, ONLY tighten it on the flat of the shaft. If you have more than one screw but only one flat surface on the shaft, only tighten the one set screw. Also… Refrain from over-tightening set screws; they need to bite into […]
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The HVAC/R Diagnosis Pyramid of Skill
WARNING: THIS ARTICLE CONTAINS GENERALIZATIONS. IT DOES NOT APPLY TO EVERYONE, AND WE HAVE ALL PROBABLY BEEN ALL OF THESE AT ONE POINT OR ANOTHER. IF YOU FEEL PERSONALLY ATTACKED, I SUGGEST FINDING A SAFE SPACE AT A WEST COAST UNIVERSITY AND BORROWING A BINKY FROM A NEARBY TODDLER. ALSO, MY CAPS LOCK BUTTON IS […]
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Milivolt Systems w/ Modern Thermostats
For those of you who don’t know, a millivolt system uses a thermocouple/thermopile with a standing (constant) pilot flame to generate a tiny “millivolt” signal used to control the furnace rather than the 24v signal modern thermostats use. There’s still a ton of millivolt furnaces out there, and many of the owners want the new […]
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A Christmas Meltdown
There’s a moral to this story, though it is a bit more of a cautionary tale than most I write. While it doesn’t rank with the story of three wise men or even Frank Capra’s Christmas classic “It’s a Wonderful Life,” you may find some common threads with both learning wisdom and remembering why throwing […]
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Ball Bearing vs. Sleeve Bearing Motors
One aspect of motor selection that can get overlooked is motor bearings, and it can have big consequences. Sleeve bearings are most common in residential and light commercial applications because they are less expensive and quieter. They don’t have rolling “balls” but rather rely on a thin film of oil on metal sleeves. Sleeve bearings […]
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An Electric Heat Mistake
I started working as a tech when I was 17 years old, fresh out of trade school. My first winter out on my own, I went to a service call in an older part of Orlando, a part of town I had never worked in before. It was an especially cold winter that year, and […]
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Try and Stay Warm
Here’s another quality tech tip from senior refrigeration and HVAC tech Jeremy Smith. Jeremy lives in Ohio, so he knows a thing or three about the cold. As HVAC/R techs, we’re often called on to work in some of the worst weather conditions. With the cold weather, I thought it timely to share some tips […]
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Clocking a Gas Meter (It’s not that hard)
I’ve heard a lot made of clocking gas meters over the years, and honestly, in Florida, there isn’t too much call for heat. There are even fewer furnaces. I was pleasantly surprised when I found out how easy it actually is. Here is how you do it, step by step: #1 – Make sure all […]
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Recovery Tank Capacity
  To start, I’m going to cut straight to the part that most of you want to know. This information is based on calculations I have done personally based on typical Mastercool DOT tanks, but feel free to come to your own conclusions based on your own calculations. I prefer to stay on the safe […]
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