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Instructors

The concept of superheat

October 19, 2021

We illustrated the concept of superheat in last week's article by boiling water and superheating steam in a moonshine still. This week we will apply this concept to refrigerant in an air conditioning system.  The still has been replaced with an evaporator. 
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Over 500 automotive scholarships available

October 14, 2021

The University of the Aftermarket Foundation (UAF) is now accepting scholarship applications for the 2022-2023 school year on its Automotive Aftermarket Scholarship Central website. Scholarships from UAF and more than 40 donor organizations are consolidated and easily accessible at AutomotiveScholarships.com.
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Understanding and troubleshooting data lines on heavy-duty trucks

September 23, 2021

Understanding and Troubleshooting data lines on heavy-duty trucks will be presented byLarry Turay of LETCO Enterprises. In Larry’s Saturday morning class, attendees will learn how components and subsystem inputs and outputs can influence HVAC operations. 
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A burned clutch is a symptom of another problem

September 14, 2021

Not much thought is given to compressor clutches until they fail, but they are extremely durable.  I have personally owned three vehicles that had between 200, 000 and 240,000 miles on them.  They all still had the original compressors and clutches, and they were still functioning perfectly.
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The Humble Mechanic wants to see you at MACS

September 2, 2021

Charles Sanville, better known as the Humble Mechanic is MACS Keynote Speaker. Come see Charles on Thursday, September 30 at 11:30am at The Rosen Centre Hotel in Orlando, FL.
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Back to school bus A/C

September 1, 2021

Since it’s September (and another school year is upon us), we’re going to look at what’s so different about school bus A/C as compared to the more common automotive-type systems.
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Mind the compressor clutch gap

August 31, 2021

One of the first things I was taught in my A/C training was to always check the clutch air gap prior to installing a compressor. 
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Mysterious servicing issue in R-1234yf systems

August 11, 2021

Recently a 2017 R-1234yf Honda system, with 72,099 miles, encountering a loss of cooling (slow leak) over time would not pass the equipment charge procedure and the production amount could not be charged. 
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Field study: Incorrectly installed condensers

August 10, 2021

I have handled numerous tech calls involving older GM trucks with incorrectly installed condensers.  In preparation for this series of MACS blogs, I discovered a salvage truck with one of these condenser repairs.  This gave me the opportunity to duplicate the incorrect installation and look for pitfalls and solutions.
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Finding right side up

August 3, 2021

Most condensers have different fittings on the inlet and outlet.  The locations of the inlet and outlet on most condensers will not allow lines to be connected incorrectly, even if the fittings do happen to be the same size.  Lastly, the designs of the mounts on most condensers prevent a unit from being installed upside down.  However, none of these characteristics apply to the condenser the technician had installed. 
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