Why You Need a Torque Wrench (or Two…)
I’ve got a confession to make. I’m “that guy.” Call it OCD, call it being anal-retentive, but I’m always making an effort to be as technically correct as possible. One aspect of that effort has been the use of torque indicating or torque limiting tools when tightening fasteners. It started after I put new valve […]
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R22 Retrofit Tips
The price of R22 is getting ridiculous, and one of the #1 requests I have been getting is for recommendations on other refrigerants to use in place of R22 and best practices, so here we go. No, you shouldn’t mix There are NO refrigerants that you are supposed to use to top off an R22 […]
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Leak Detection on Large Systems
Imagine, if you will, a 20-year-old kid. He has no formal training in the HVAC/R field, only ride along “training” and book learning as he reads along with his journeyman father with whom he’s riding. One stormy summer evening, a service call comes in for an ice cream freezer down. After calling and talking to […]
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No, It’s NOT a Ground!
I was walking around at the AHR conference today, and I stopped at the booth of a popular hard start kit manufacturer (especially popular with white-shirt sales techs). I listened to the guy behind the booth “training” some municipal maintenance techs on the use of his hard start kit. (To be fair, I actually think […]
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Boiler Basics Part 4 – Piping
Please note: There have been some legitimate questions about a few of the points in this article and the diagrams. While Justin Skinner is an experienced tech and totally qualified to write this article, we will be specifically looking into the question of the best location of the circulator pump and addressing the “point of […]
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Oil Nozzles
This article was written by Senior Boiler Tech Justin Skinner. Thanks, Justin. Oil burner nozzles are present in most forced combustion air burners. They are used with an oil pump to atomize fuel oil and allow it to burn. Atomizing is raising the pressure of the fuel and forcing it through the nozzle. Essentially, the […]
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Venting for High-Efficiency Gas Furnaces – Part 2 Assembly
This article was written by senior furnace tech Benoît (Ben) Mongeau. Ben hails from the frozen tundra of Ontario, Canada, where high-efficiency gas furnaces are commonplace. While some codes and practices may be different from the US, I find that most of it is common sense and translates pretty well. One glaring difference between Canada […]
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Venting for High efficiency Gas Furnaces – Part 1 Materials
This article was written by senior furnace tech Benoît (Ben) Mongeau. Ben hails from the frozen tundra of Ontario, Canada, where high-efficiency gas furnaces are commonplace. While some codes and practices may be different from the US, I find that most of it is common sense and translates pretty well. One glaring difference between Canada […]
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Boiler Basics Part 3 – Steam
This article was written by Senior Boiler Tech Justin Skinner. Thanks, Justin. Steam plays a very important part in all of our lives, whether we know it or not. Virtually every article of clothing and accessory you are wearing right now relied on steam for either manufacturing or packaging. Hospitals use large steam boilers for […]
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