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.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 >
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.Read Article >
Helping your customer understand their A/C repair
December 16, 2021
To help service shop owners, MACS has created a 30-page consumer guide for your customers that explains how their car’s engine cooling system and air conditioning system works. “Getting to know your car’s air conditioning and engine cooling system,” details how these vital climate systems work and why they may require an extensive repair.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 >
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.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 >
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.Read Article >
