
No drier replacement, no compressor warranty!
April 6, 2022
Compressor manufacturers and parts distributors are adamant about driers being replaced when one of their compressors are installed. No drier replacement, no compressor warranty!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 >

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 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.Read Article >

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.Read Article >

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.Read Article >

Electronically controlled variable displacement compressors
November 16, 2021
what if" this system used an electronically controlled variable displacement compressor instead of the pressure controlled variable displacement compressor? What would the results be?Read Article >

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.Read Article >

What do you know about the fixed displacement piston compressor?
November 2, 2021
What do you know about the fixed displacement piston compressor?Read Article >

Bring the heat!
November 1, 2021
At this time of year, I often end up with an earworm in my head from a Canadian rock band … Summer’s going fast, the nights are growing colder. Then it’s the line everyone knows from something more mainstream … Winter is coming. It’s early September, and the leaves on some trees are already starting to change. Winter is coming.Read 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 >

Don’t try this at home
October 6, 2021
Don't try this at home! We do not recommend adding a machete to your mobile A/C tool kit. However, in Belize they do things differently. Sometimes necessity is the mother of invention.Read Article >