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Show me your MACS 609 card

May 26, 2021

When you purchase refrigerant in quantities of two pounds or more you must show your Section 609 card.If you are Section 609 certified through MACS between 1991 and May 2021...
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Temperature testing detective work: The search for a diagnosis

May 25, 2021

Last week we closed our blog post with a discussion about an orifice tube system which had an evaporator outlet temperature that was about 20° warmer than the inlet. We mentioned that this could be an indication of a restricted orifice tube or a refrigerant undercharge. In applying this to diagnostics, it is important not only to understand what this represents, but also why.
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What is your temperature testing data telling you?

May 18, 2021

If air conditioning systems were transparent where we could see inside them, then diagnostics would be faster and easier. We could look at the systems and see things right away that affect system operation, like restrictions and liquid levels in evaporators and condensers.
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Do you have the essential tools for success?

May 17, 2021

Using the correct tools to service and repair vehicles is so important that the Society of Automotive Engineers (SAE) creates standards for some service tools to meet. Requirements for their use by service professionals is included, as well. Some examples include refrigerant recovery and recycling machines, refrigerant identifiers and leak detectors.
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Pass the temperature probe

May 4, 2021

The first step is to run the A/C system for a few minutes to let it stabilize. Then both probes should be connected side by side at both points that will be temperature tested in the system. For example, if you were testing the temperature drop across the condenser, this would need to be done on both the discharge line and the liquid line.
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Are you using the right tools for mobile A/C repair?

April 30, 2021

Your shop’s R-134a recovery/recycling/recharge (R/R/R) machine is in well-maintained condition. You have an R-1234yf gauge manifold set and an R-1234yf machine is on order; should arrive shortly.
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Contact counts in temperature testing

April 27, 2021

Proper contact is vital when connecting to A/C lines using the contact type temperature thermometers. To determine if I am getting good contact, I always like to place both connectors side by side on the same line and observe the temperature readings.
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MACS Mobile A/C Update Webinar Now Available On Demand

April 22, 2021

Every year the Mobile Air Climate Systems Association creates a special mobile A/C update clinic to help working technicians keep up with the rapidly changing mobile A/C service and repair...
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Tips for taking your mobile A/C system’s temperature

April 20, 2021

The contact type units do indeed have a high degree of accuracy, but precautions must be taken when using them (especially connecting to lines) to ensure the accuracy. Otherwise, it is possible to get readings that are easily 5° to 10° off and that can lead to an incorrect diagnosis.
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The pressure is on

April 19, 2021

By appearance, radiator caps seem to be a simple device. Yet, many technicians do not understand the cap’s real function
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Temperature testing accuracy

April 13, 2021

Temperature readings can be easily used to determine if an orifice tube system might be undercharged, and they can also be used to charge an orifice tube system. But if the readings are not accurate, all they are going to do is cause you problems.
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Then things got complicated!

April 9, 2021

It was a 2013 Camaro. The complaint was poor cooling and the temp really would not change when you switched it from heat to cool. In diagnosing the job, the technician found the blend door was stuck to where it was blending heat. Until it was pulled out, the tech was not sure if it was a bad actuator or door.
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