Relative Humidity in the Supply Air Stream
When you first start checking your supply air with a thermo-hygrometer you may notice that the relative humidity is REALLY HIGH. Often the RH in a supply duct will be between 85% and 96% relative humidity on a system that is functioning as designed. The reason for this is fairly simple. In order for dehumidification […]
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Sealing Boxes / Boots / Cans
The tech tip today is a video put out by my friend Brad Hicks from the HVAC in SC YouTube Channel. Thanks Brad! Ok, so this has nothing to do with raccoons but I like that photo. Whenever you are installing duct boxes (also called boots or cans) in an aftermarket application, make sure to […]
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Bending EMT
I was about 13 years old the first time I bent EMT with my uncle. We were doing a renovation at a church, and watching him bend EMT and then getting to do it MYSELF was a truly religious experience. There are a few things in the trade where workmanship really comes into play such […]
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Cased Coil Misalignment
On occasion you will either find a furnace or be tasked with installing a furnace where the coil overlaps the edge of the furnace because the coil is wider. In the case of a Carrier CNPVP coil you need to ensure that you align the coil according to manufactures specs or you risk cutting off […]
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What are Dry and Wet Contacts?
I was talking about dry contacts with one of my techs, and he was looking at me like I had three heads—and one of them was on fire. So, I figured it would be good to cover the difference. Basically, a “dry” contact is a switch with no shared power source or supply integral to […]
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Electronic Leak Detection DOES WORK
I hear many techs complain about the finicky and ineffective nature of electronic leak detection. So much so that some claim that it is a waste of time altogether. We recently located a leak inside the fins of a ductless evaporator coil—pinpointed to an exact spot—using an electronic leak detector. For demonstration purposes, we took […]
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Ductless Cleaning and Maintenance Start to Finish
  Cleaning ductless systems is critical… and a pain.. Rather than just telling you how we do it let me show you some of the key points. This video demonstrates cleaning and testing a ductless system including pulling the blower wheel and washing the evaporator with a bib kit.   I also wrote a process for […]
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Testing the Leak Rate on Your Micron Gauge Itself
As a technician gains skill they will learn that regularly testing your tools is a huge part of success. It isn't long in the field before techs find out that just because a meter or gauge gives a particular reading it doesn't ALWAYS mean it is correct. Vacuum is one of these areas. Everything in an […]
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How to Evacuate an Air Conditioning System (Fast and Deep Vacuum)
Evacuation Start to finish with some of the best evacuation practices. Click below to see the video. –Bryan
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