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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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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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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Don’t Forget the Panel
See the photo above? This is a unit we (my company) serviced for a commercial customer. It doesn’t matter if we aligned the belt, dialed in the charge, cleaned the condenser (using THIS thorough process), and got the drain pan clean. We look like dummies because the panel fell off. Also, as you may notice, […]
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How to Use the Progress Ratchet
Do you remember the first time you used a ratchet? Neither do I, but I DO remember the context in which I first used one. In order to understand my story with ratchets, I need to introduce you to my grandpa, Don, the man who I have always called “Papa.” My grandpa has done so […]
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The Slow Death of the Honest Technician
I was sitting in a session at the HVAC Excellence educators conference (which was excellent, by the way), and my phone buzzed. So, like a typical punk kid, I looked down at it to see that my friend Josh had sent me a Facebook message asking if we served the east side of Orlando because […]
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Know the Limits of Subcooling
This article was written by RSES CM and excellent market refrigeration tech Jeremy Smith. Thanks, Jeremy! I frequently see techs online struggling with charging or troubleshooting refrigeration equipment and using subcooling as a diagnostic or charging method. Please don’t do this unless you understand it fully. Many times, trying to charge a refrigeration system to […]
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