Truck/Trailer Refrigeration Unit - Sunbelt Transport Refrigeration

they are not suited for evacuation purposes.) to thevacuum pump and refrigeration unit. Also, as shown,connect a evacuation manifold, with evacuation hosesonly, to the vacuum pump, electronic vacuum gauge, andrefrigerant recovery system.c. With the unit service valves closed (back seated) andthe vacuum pump and electronic vacuum gauge valvesopen, start the pump and draw a deep vacuum. Shut offthe pump and check to see if the vacuum holds. Thisoperation is to test the evacuation setup for leaks. Repairany leaks if necessary.d. Midseat the refrigerant system service valves.e. Open the vacuum pump and electronic vacuumgauge valves, if they are not already open. Start the vacuumpump. Evacuate unit until the electronic vacuumgauge indicates 2000 microns. Close the electronic vacuumgauge and vacuum pump valves. Shut off the vacuumpump. Wait a few minutes to be sure the vacuum holds.8f. Break the vacuum with clean dry refrigerant. Userefrigerant called for in the unit specifications. Raisesystem pressure to approximately 2 psig.g. Remove refrigerant using a refrigerant recoverysystem.h. Repeat steps (e) through (g) once.i. Evacuate unit to 500 microns. Close off vacuumpump valve and stop pump. Wait five minutes to see ifvacuum holds. This checks for residual moisture and/orleaks.j. With a vacuum still in the unit, the refrigerant chargemay be drawn into the system from a refrigerantcontainer on weight scales. The correct amount ofrefrigerant may be added by observing the scales. (Referto section 4.10)7431110491. Refrigerant Recovery Unit2. Refrigerant Cylinder3. Evacuation Manifold4. Valve5. Vacuum Pump6. Electronic Vacuum Gauge7. Evaporator Coil8. Receiver Outlet (King) Valve9. Condenser Coil10. Suction Service Valve11. Discharge Service Valve21645Figure 4-10. Single Vacuum Pump Connections4-11 62-02884