ACtion Magazine - May 2012 - (Page 20)

New tools and tricks from the MACS Trade Show he A/C service industry is keeping its eye on the ball – the R-134a ball that is. Yes, there were a lot of questions about the forthcoming R-1234yf. But the MACS Trade Show and all the technicians walking its aisles maintained focus on what it takes to service today’s R-134a system and those they’ll be seeing for years to come. There will never be retrofits to R-1234yf, except possibly for a handful of environmentally exuberant owners with lots of extra cash in their wallets—R-1234yf’s claim to fame is its very low global warming number (4 vs. 1434 for R-134a). This refrigerant not only is about 10 times the price of our current R-134a, but also mildly flammable and has a different density, so an R-1234yf evaporator must meet a new SAE standard for robust construction and resistance to corrosion. Further, the suction hose may be a different diameter and the expansion valve calibration is different, so these also would have to be replaced. And to match R-134a performance, an internal heat exchanger (a new component installed across the low and high side lines) also would have to be installed for a retrofit. Fear not. There will be R-134a production for many years to come, both as an OE refrigerant and to service existing R-134a systems. T These two machines, from Robinair and Bosch/RTI, are designed to meet the SAE standard for R-1234yf. They have anti-arcing switches and motors, and special internal venting for safety in case of refrigerant leakage. The machines must identify the vehicle refrigerant as R-1234yf before recovery can begin, and also perform vacuum/pressure decay checks to confirm there is not a gross leak before recharge. 20 ACTION • May 2012 So yes, although there were a couple of R-1234yf recovery/ recycle/ recharge (RRR) systems on display at the show, the exhibitors admitted they were aimed primarily at car dealers, with a small number of sales to those independent garages that service A/C for body shops and or do certain work for car dealers. The exhibitors were Robinair and Bosch/RTI, and a few days after the trade show it was announced that Robinair’s parent company, SPX Service Solutions, is being acquired by Bosch Automotive Aftermarket Division. Some consolidation of the Robinair and RTI product lines may occur, although there’s no information at this point. These new machines must identify the refrigerant in the vehicle system as R-1234yf before recovery can begin, so they must be equipped with an identifier that meets SAE J2927 (built into the machine) or have a USB port for a signal from a hand-held identifier that meets SAE J2912. You may choose to just acquire some R-1234yf capability “in case,” but not make the major expenditure for an R-1234yf RRR machine at this time. A manifold gauge set is one possibility, something that you’ll eventually need and for diagnostics might use sooner than later. Mastercool had one on display and although pressure gauge readings are pressure gauge readings, the hose couplings are specific for R-1234yf. You might be able to pick up new service hoses for your existing gauge manifold, but you probably won’t want to keep swapping hoses. The new refrigerant identifier is surely a must, for more than one reason. The high price of R-1234yf makes it likely that some leaking systems will be changed to or at least topped up with R-134a; you have to be able to identify them to avoid contaminating an RRR machine. Because the R-1234yf systems were designed for that refrigerant, there is no performance advantage of a changeover to R-134a, and a 50-50 mixture of the two refrigerants produces 8% higher pressure gauge readings. A 50-50 mixture, from a top up with R-134a, also could lead to misdiagnosis or potentially early triggering of control switches and sensors. In addition, the global warming reduction from R-1234yf would be lost. A new issue is counterfeiting of R-134a tanks. Some counterfeit tanks actually contain R-40 (methyl chloride), a highly-toxic, flammable refrigerant that reacts with aluminum and then becomes explosive on exposure to air. Only the new R-1234yf identifiers have been engineered to indicate R-40 contamination of a system or tank. A current generation premium design with a digital display can be used to test what is supposed to be a virgin R-134a tank. And if the identifier display shows any air content (4% or higher would be huge for what is supposed to be virgin R-134a), you can suspect contamination with R-40, which produces the misleading air indication. But for positive ID in a vehicle system, you need a next generation identifier.

Table of Contents for the Digital Edition of ACtion Magazine - May 2012

ACtion Magazine - May 2012
Table of Contents
Outlook
Expansion Valve
Technically RELAY-ted
Under the Southern Cross
Leonard’s Law
Cooling Corner
Virtual View
News & Updates
New Tools and Tricks From the MACS Trade Show
Vacuum: How Much Is Enough?
“Universal” Compressor Oil?
Association News
Quick Check
New Products & Services
Last Watch

ACtion Magazine - May 2012