p Figure 1 - A screenshot from Mitchell 1 ProDemand illustrating the A/C system specifications for a 2009 Toyota Prius. GM did use 150 in the 1990s and early 2000s. PAG oil is also used with R-1234yf refrigerant. Use your repair information to research the correct oil (and amount) along with the correct refrigerant charge for the vehicle that you are servicing. You can see the required specifications from Mitchell 1 ProDemand for a 2009 Toyota Prius (Figure 1). Remember that when replacing A/C components, they should be drained of all oil, and the collected oil should be measured to ensure the correct amount of oil is put back into the system. Either too little or too much oil can potentially damage the compressor. For servicing R-134a, we've used a Robinair 34788 machine for the past 15 years (Figure 2). It has serviced hundreds of vehicles throughout its life. We have been religious about machine maintenance by changing the compressor oil and the internal filter. However, we did run into a problem with the internal solenoid valves sticking. The machine got damaged due to servicing a vehicle that had stop-leak (a system sealing fluid) installed in the A/C system (that we were not aware of until after the fact). We typically avoid servicing those vehicles if we know the customer has used a " stop-leak " type product. There is one drawback to this A/C machine, it cannot flush the A/C lines. As a result of this, we do not use this machine to COMMANDER4000 R1234yf & Hybrid Recovery/Recycle/Recharge Machine RECOVERY / RECYCLE / RECHARGE MACHINES * 8 " COLOR TOUCH SCREEN to navigate all features and functions with ease * WIFI CAPABILITY allows for real time, interactive communication and troubleshooting * VISUAL INDICATOR LIGHT provides visual confirmation of machine progress * 4 " ANALOG GAUGES are class 1 rated and color coded 12 EN 837-1 CLASS 1.0 mmHg In Hg 500 bar psi Keeping the Busy Technician in Mind... WWW.MASTERCOOL.COM 2303PTEN_Mastercool.indd 1 * Refrigerant identifier * Hose flushing * Thermal printer * One used oil bottle * Status light * Refrigerant database * SAE J2843 certified * Made in USA COMMANDER2000 R134A Fully Automatic Recovery/Recycle/Recharge Machine * Automatic oil injection * Two sealed bellows design bottles, one used oil bottle * Status light * Refrigerant database * SAE J2788 certified * Made in USA PHONE: 973-252-9119 * FAX: 973-252-2455 Circle 77 on card or click " PTEN e-inquiry " on VehicleServicePros.com www.VehicleServicePros.com MARCH 2023 PROFESSIONAL TOOL & EQUIPMENT NEWS 21 2/2/23 1:08 PM 200 -760 30 D R E T 150 A R 250 6 300 100 50 24 350 225 325 275 175 15 125 75 25 3 9 18 21http://WWW.MASTERCOOL.COM http://www.VehicleServicePros.com http://www.VehicleServicePros.com