● Includes 1/2 in. ACME (R134a) and R12 connectors ● Vacuum level: 28.3 in. of mercury at sea level ● Air consumption: 4.2 CFM @ 90 PSI ● Air inlet: 1/4 in.-18 NPT1. Connect user supplied A/C Manifold to system. (Be sure all manifold valves are closed before connecting) 2. Connect the center hose of the Manifold Gauge Set to the “Vacuum” tee fitting (either R-12 or R-134a) on the front of the pump. Tightly cap the port not used. 3. Open both valves on the manifold 4. Connect compressed air supply to Vacuum Pump Inlet. The low side gauge should drop below zero and continue falling. Once gauge reaches its lowest point, let the vacuum pump run for at least 10 and preferably 20 minutes. 5. Closed both manifold valves and disconnect air supply from the vacuum pump. 6. Let system stand for at least 5 minutes to ensure the system is not leaking. If the gauge does not move, no leaks exist. 7. Follow manufacturer’s instructions to recharge AC System.1. Always store the Air Operated Vacuum Pump Set in a well-protected area where it will not be exposed to inclement weather, corrosive vapors, abrasive dust, or any other harmful elements. 2. Keep the Air Operated Vacuum Pump clean for better and safer performance.A vacuum pump is a literal workhorse in aftermarket air conditioning. Once you’ve chosen and purchased the right pump, your goal should be to protect and maintain your investment. Because it removes moisture, acid and other contaminants from an A/C Importance Of Checking And Changing Vacuum Pump Oil It’s a question we hear all the time at Poly Run. “Do I REALLY need to change my vacuum pump oil?” The answer is a resounding, “Yes—for the sake of your vacuum pump AND your system!” Vacuum pump oil is a crucial How To Vacuum An Automotive A/C When a mobile A/C system needs to be repaired, the first step taken is usually to recover the refrigerant from the system for reuse later. An A/C vacuum pump is used to remove unwanted air and water vapor. Tips For Charging Automotive Air Conditioners Most people assume if their A/C is blowing warm that they are low on refrigerant. However, this is not always the case. Therefore, when charging A/C systems, it is recommended to evacuate the system before adding refrigerant.