Air contamination in an A/C system can ruin your day
February 2, 2022
I had a memorable encounter with air contamination in the mid 1990s. I was conducting a lot of retrofit clinics at the time and had recently acquired a demo refrigerant identifier which I took to those clinics. At one clinic, there was a technician who was extremely interested in the refrigerant identifier.Read Article >
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 temperaturesRead Article >
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.Read Article >
Behavioral characteristics of various compressor types pt. 2
October 5, 2021
So now it is time to provide the correct answer along with information on why it is correct and also information on why the others are incorrect.Read Article >
Behavioral characteristics of various compressor types
September 21, 2021
When faced with a challenging A/C system problem, knowing what type of compressor you are dealing with can help streamline the diagnosis process.Read Article >
MACS Tesla project
August 26, 2021
MACS is working on a project, to collect A/C charge information for Tesla vehicles, and we need your help!Read Article >
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.Read Article >
Top three tips on orifice tube behavior
July 20, 2021
In the last four MACS blog articles we covered a lot of detailed information about orifice tube system behavior. We examined a system with a full refrigerant charge verses a 25% undercharge. Now it is time to condense it all down into three important takeaways.Read Article >
Low refrigerant charge and the search for real data part 4
July 13, 2021
When we examined the pressure readings and vent temperature readings last week, there was nothing showing up that indicated any charge issues (even operating with the 25% undercharge).Read Article >
Low refrigerant charge and the search for real data part 3
July 6, 2021
To place as much heat load on the system as possible, we turned the heat in the shop up on high and got it as hot as possible before beginning the test. When the temperature peaked at 89°, we began the test. We tried to keep it constant, but all the heat being generated by the engine in the test vehicle caused it to inch upward by 2.5° before the second test was concluded.Read Article >
Low refrigerant charge and the search for real data: part 2
June 29, 2021
The purpose of the test was to run an orifice tube system with a full refrigerant charge and then with a 25% undercharge and compare pressure readings and temperatures at strategic points in the system.Read Article >
What’s the word on R-134a price & supply?
June 24, 2021
The email questions are already coming in, and they go kind of how you’d expect: What’s going on with the price of R-134a? Is there going to be a shortage of R-134a supply?Read Article >
