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Read all about it!

February 1, 2022

Read all about it! MACS February 2022 digital issue of ACTION magazine is ready to view.
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Long exposure of car driving down highway

MACS changes leadership

January 31, 2022

MACS is changing leadership. Elvis L. Hoffpauir, is stepping down at the end of January 2022 from his duties as MACS president and chief operating officer to enjoy retirement. Following a 42-year distinguished career at the Mobile Air Climate Systems Association (MACS), Elvis will transition to past president and association advisor.
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Heater Insight

January 25, 2022

Recently, a customer brought in a 2006 Honda Insight with a heater that was blowing cold but had no other vehicle concerns. A local garage had informed the customer the head gasket had failed; however, the owner felt a second opinion was necessary.
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The effects of air contamination in an A/C system

January 11, 2022

If you perform an Internet search for effects of air contaminated refrigerant on automotive A/C system pressures, you’ll find many results.  This information leaves no doubt that air contamination of refrigerant in an automotive A/C system can affect system pressures and temperatures
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Variable output scroll compressors

January 5, 2022

This compressor has been around for quite some time and the vehicles it is used on are getting some age on them.  However, they still show up in shops with regularity and there still seem to be a lot of technicians that are not aware of the problem, diagnostic procedure and cure. 
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When you don’t know about clutch wires

December 27, 2021

The conversation involved a clutchless compressor unit. A CSR who had sold one to a shop contacted me and said his customer (who was both the shop owner and technician working on the car) had just called him. There was a concern that the compressor didn't have a clutch wire.
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An overview of electronic variable displacement compressors

December 21, 2021

we have focused on electronically controlled variable displacement compressor operation and behavior.  It is important to have a good understanding of how these compressors operate and behave. This is because the percentage of vehicles coming into shops using these units is growing and will continue to grow.
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The pulse width modulated duty cycle signal

December 7, 2021

Several years ago, when vehicles using these compressors were just starting to show up at shops for service with some regularity, we were searching to find some detailed information about their behavior to use in clinics.  There was not a lot of it available, so we borrowed several vehicles and did some videos.  The following are some clinic slides produced from one of those videos.
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Diagnosing electronically controlled compressors

November 30, 2021

When preparing to conduct diagnostics on a system using an electronically controlled variable displacement compressor, the diagnostic process needs to focus on four areas.
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Exploring electronically controlled variable displacement compressors

November 23, 2021

Electronically controlled variable displacement compressors (ECVDs) have been in use now for over 15 years.  However, there are a lot of technicians in the field who have very little knowledge about them and their operation.
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Troubleshooting the “what ifs” in a mobile A/C repair

November 9, 2021

High side:  Likely somewhere around 130 psi (at an idle) & 140 psi at 1500 rpm.  Why? With only a 35% charge in the system, the compressor isn't going to be producing a lot of pressure.
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Meet MACS member, Tom Lech

November 8, 2021

Stationed in San Francisco, California, Thomas Lech has maintained a bustling business for almost three decades. Lech Auto Air Conditioning has been busy for 365 days a year from opening at 7 a.m. to closing at 7 p.m. for the last 27 years, with summertime only increasing the demand for the shop’s services.
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