Some Important Terms to Know
In my recent classes with my employees at Kalos, we've been going over finding target pressures and temperatures for an air conditioning system. The goal has been to get techs to have “target” readings in mind before they start connecting tools. This step is an important part of being able to “check a system without […]
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Testing, Recovery, and Charging a Sealed System
There are many appliances with compression refrigeration circuits that do not have ports installed for testing, recovery, charging, and evacuation.  These can include window units, PTACs, fountains, refrigerators, and much more. This fact presents a challenge any time you suspect or know there is a refrigerant circuit issue. How can you diagnose and repair when […]
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Two Less Common TXV Issues to Watch For
The most common diagnosis with expansion valves is failed closed or restricted, resulting in underfeeding of the evaporator. The symptoms are low suction, normal subcooling, and high superheat when a TXV fails “shut,” but there are some other issues to watch for that can actually result in overfeeding the coil. Schrader in the Port The […]
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Thoughtful Termination (Of Wires)
When you are checking a unit of any kind, you should be keeping your eyes open for signs of arcing and melting at all of your wire connections and contact points. We find issues with melting terminals on contactors and in disconnects regularly. Still, We rarely think about the relationship between circuit ampacity, wire size, […]
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Introduction to Pool Heat Pumps
Air-to-water pool heat pumps are seeing more and more popularity in the climates that can support them over the more traditional gas and electric pool heaters we usually see. While they definitely contain some familiar operating principles to an air-to-air heat pump, there are some striking differences in how the heat is transferred and how […]
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No, Recharging R22 Isn’t “Illegal” in the US
If you remember my recent article on the company that went to my friend's house for a PM and did nothing but leave a system quote. Well, it got worse… My friend Josh left them a D-rated review on a popular review site, and the owner of the company responded with… an apology? A bottle […]
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An Old Timer’s Trick to Get Unstuck
I once had an old commercial blower assembly on a 20-ton package unit, and the bearings and pulleys were seriously shot. I was 19 or 20, and as much as I tried, I just couldn't get the rusted hunk of metal apart. I tried penetrating oil, pullers, pry bars… I knew better than to beat […]
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Multimeter Categories
Testo 760 Category IV Multimeter I was standing at a booth at the HVAC Excellence Educators conference, and an instructor walks up, grabs a meter, and asks me, “What's the difference between a category 3 and a category 4 meter?” Well, I really wasn't sure, but I knew that the category 4 meter is rated […]
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Removing Water From a Float Switch
We all have some weird tools we keep in our tool bags. A baster may look suspicious, but it comes in really handy for removing water from a float switch. This one is extra handy because it comes with a nice tapered bottle brush inside it that works great to clean out the outlet port […]
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