Flash Gas
When we say that there is “flash gas” at a particular point in the system, it can either be a bad thing or a good thing, depending on where it is occurring. Flash gas is just another term for boiling. It is perfectly normal (and required) that refrigerant “flashes” or begins boiling directly after the […]
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What You Know About Start Winding Inrush Current Might Be Wrong
Take a look at the specs from this Copeland scroll compressor pulled from the Copeland Mobile App (which is an incredible app, by the way). These specs are for a single-phase compressor, so the amperages listed are based on an amperage reading from the wire connected to the common terminal. LRA is the locked rotor […]
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Making a Flare – Quick Tips
This article is not a full lesson on making a flare, but it will give you some best practices to make a flare that doesn't leak. First off, we need to clarify that very few unitary manufacturers use flares anymore. You will most often find flares on ductless and VRF/VRV systems and in refrigeration. A […]
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What’s the Scoop on PM10 and PM2.5 Particles?
MATLAB Handle Graphics It was December 5th, 1952, only seven years after the end of WWII, in London, England, when the “Great Smog” settled across the city. The “great smog” was the result of a meteorological anomaly combined with unchecked industrial pollution. Still, even once it settled on the city, bringing business to a screeching […]
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Negative Superheat? Time to Check Your Tools
I was fresh out of school, working as an apprentice at my first real HVAC job, and I was listening in on a shop conversation between a few techs. They were talking about finding so many overcharged systems. One of the techs turns to me and says, “I had a unit yesterday that was so […]
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Setting & Checking Charges in the Rain
I live in Central Florida, and while it can get pretty hot in the summer, we also tend to get afternoon thunderstorms that come and go in a flash. I have been connecting gauges, checking charges, and even pulling vacuums in the rain (even under umbrellas or cardboard boxes) for most of my career. Only […]
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8 Tips for New Techs (So You Don’t Get Fired)
If you are new to the trade, I'd like to welcome you. Like many skilled trades, the HVAC/R trade has many opportunities and can help you make a good living. We need those of you who are young and new to the trade, and we are grateful to have you. But as a word of […]
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Top Residential A/C Maintenance Tips
A while ago, Bert made a video about his top residential A/C maintenance service tips. He showed some pretty good practices in there, so we’re going to revisit them in this article. Maintenance procedures are vital to any HVAC business, especially those specializing in residential A/C. When we do preventive maintenance, the customers see our […]
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Beware of “Ghost” Voltage
Disclaimer: “Ghost voltage” is a term used by techs to explain a phenomenon where they measure voltage they don't expect or when the voltage they see doesn't do the work they expect. More advanced techs know how to use the Lo-Z (low impedance) mode on their voltmeter if it has one to help eliminate this. […]
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