MACS Service Reports - 2016 - JUN1

Total Vehicle Climate and Thermal ManagementTM

June 2016

By Paul Weissler, MACS Senior Technical Correspondent
R-1234yf RECYCLING MACHINE BUYING GUIDANCE - AN IMPORTANT CAUTION AGAINST BUYING AN

dual machines can be made either in versions that
switch back and forth or start out produced to work
with one refrigerant (R-134a) and with installation of a kit, become capable of servicing (only)
R-1234yf systems.
However, we also have spoken to shops that had
purchased a dedicated R-134a machine (FIGS 1)
within the past year or two,
love it and see no reason to
buy anything but a dedicated
R-1234yf unit, that meetsSAE
J2843. We can't disagree if
that's the way you feel, as the
single refrigerant machine
is somewhat less expensive.
There shouldn't be a mammoth price difference, because after all, the J3030 machines are basically built to
J2843 specifications to meet
flammability safety specifiFigure 2: Like other compacations (anti-arcing switchnies, CPS designed a whole
new family of machines, ines, safety venting to prevent
cluding this one engineered
refrigerant vapor buildup
to meet SAE 3030. It services
in the cabinet, etc.) and also
both R-134a and R-1234yf
must include refrigerant
systems, on a back and forth
basis.
identification.

Paul Weissler

Bosch/Robinair, Mahle/RTI, Ritchie

If you've been reading MACS Service Reports
periodic articles on new equipment for R-1234yf
systems, you know that we've been promoting the
idea of waiting for machines that meet SAE J3030.
This engineering standard covers both refrigerants
(combining J2788 for R-134a and J2843 for R-1234yf,
plus a test for excessive cross-contamination). The

"UNLOCKED" MACHINE

Figure 1: SAE J2788 has been in effect for over nine years, and the leading manufacturers have all redesigned their R-134a machines. New
housings, improved control systems and even more efficient operating
cycles have been engineered into the equipment. So with engineering to
reduce costs also part of the equation, it's not surprising that shops with
older R-134a machines are looking longingly and therefore buying new
ones, particularly if the salesmen offer attractive pricing.

ALSO INSIDE THIS ISSUE:
"Have I Got A Deal For You" - The "Unlocked" R-1234Yf Machine............................................................................... 2
Sensible Buying Schedule ................................................................................................................................................ 3
Should You Say Goodbye To That "Rule Of Thumb" On Condenser Temperature Drop Testing ............................. 4
Still Another (Related) Issue To Temperature Drop Testing .......................................................................................... 6
Everything Started Out Well ............................................................................................................................................. 7

MACS Service Reports is the official technical publication of the
Mobile Air Conditioning Society Worldwide, Inc., P.O. Box 88,
Lansdale, PA 19446. The material published in MACS Service
Reports expresses the views of the contributors and not necessarily that of MACS. Every attempt has been made to ensure

June 2016

the accuracy of the content of MACS Service Reports. MACS,
however, will not be responsible for the accuracy of the information published nor will MACS Worldwide be liable in any way for
injury, labor, parts or other expenses resulting from the use of
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MACS Service Reports

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