It isn’t blowing cold enough
June 29, 2022
"It isn't blowing cold enough.” Most any auto repair shop that does A/C work will often hear customers say this phrase. It can be the result of any number of things that can be wrong with an A/C system. Often it is a case of common things such as, a low refrigerant charge, a refrigerant overcharge, contaminated refrigerant, a blend door issue, a cooling fan problem, or maybe a weak compressor.Read Article >
The importance of A/C system oil balancing
June 21, 2022
Sometimes we encounter information where directions instruct us to drain the compressor being removed from a system and measure the amount of oil that drains out. Then the next step is to subtract this number from the number of ounces that are supposed to be in the shipped replacement compressor.Read Article >
A look at the new standard in mobile air-conditioning chemistry
June 6, 2022
Since Packard offered the first automobiles with factory air-conditioning in 1939, mobile cooling has been driven by R-12 and R-134a (both refrigerants in the Freon™ product family), followed by what is quickly becoming today’s standard, R-1234yf.Read Article >
The desiccant myth
April 12, 2022
There is a myth that exists involving A/C service work and driers that seems to come up from time to time. I have encountered it when handling tech calls and have seen it come up in A/C forums. Read more to find out what it is.Read Article >
What does a MACS Section 609 card look like?
March 10, 2022
MACS occasionally receives reports from the field of a technician being refused purchase of refrigerant for not having a proper Section 609 card. Usually this is due to the technician not producing the right card or the counterperson not understanding what a MACS Section 609 card looks like. What does a MACS Section 609 card look like?Read Article >
Refrigerant supply, pricing and safety
March 8, 2022
What I'm hearing about refrigerant supply and pricing this year reminds me of a similar period in the mid-2000s. It was springtime, just before the start of A/C season. Supplies of R-134a were tight and the price had come close to tripling from the prior year.Read Article >
Checking for refrigerant contamination
February 24, 2022
A large percentage of MACS members have refrigerant identifiers and use of them on vehicles that come into their shop for A/C service prior to beginning any service work is standard procedure. However, there are a lot of non-MACS member shops who do not have identifiers and unfortunately are not aware of the potential issues which can be caused by refrigerant contamination.Read Article >
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 >
AEM Update: Snap application for off-highway R-1234yf
September 22, 2021
MACS will have a variety of heavy-duty and off-road presenters beginning at 8 am on Thursday, September 30. One will be AEM Update: Snap application for Off-highway R-1234yfRead Article >