ICE MACHINES Q-Model Service Manual

Section 7Refrigeration SystemNORMAL REMOTE MODEL PROCEDURESRefrigerant Recovery/EvacuationDo not purge refrigerant to the atmosphere. Capturerefrigerant using recovery equipment. Follow themanufacturer’s recommendations.ImportantManitowoc Ice, Inc. assumes no responsibility forthe use of contaminated refrigerant. Damageresulting from the use of contaminated refrigerant isthe sole responsibility of the servicing company.ImportantReplace the liquid line drier before evacuating andrecharging. Use only a Manitowoc (O.E.M.) liquidline filter drier to prevent voiding the warranty.CONNECTIONSImportantRecovery/evacuation of a remote system requiresconnections at four points for complete systemevacuation. See the drawing on next page.Make these connections:• Suction side of the compressor through the suctionservice valve.• Discharge side of the compressor through thedischarge service valve.• Receiver outlet service valve, which evacuates thearea between the check valve in the liquid line andthe pump down solenoid.• Access (Schrader) valve on the discharge line quickconnectfitting, located on the outside of thecompressor/evaporator compartment. Thisconnection evacuates the condenser. Without it, themagnetic check valves would close when thepressure drops during evacuation, preventingcomplete evacuation of the condenser.NOTE: Manitowoc recommends using an access valvecore removal and installation tool on the discharge linequick-connect fitting. This permits access valve coreremoval. This allows for faster evacuation and charging,without removing the manifold gauge hose.REMOTE RECOVERY/EVACUATION1. Place the toggle switch in the OFF position.2. Install manifold gauges, charging cylinder/scale, andrecovery unit or two-stage vacuum pump.3. Open (backseat) the high and low side ice machineservice valves.4. Open the receiver service valve halfway.5. Open high and low side on the manifold gauge set.6. Perform recovery or evacuation:A. Recovery: Operate the recovery unit as directedby the manufacturer’s instructions.B. Evacuation prior to recharging: Pull the systemdown to 250 microns. Then, allow the pump torun for an additional hour. Turn off the pump andperform a standing vacuum leak check.NOTE: Check for leaks using a halide or electronic leakdetector after charging the ice machine.7. Refer to Charging Procedures.Part No. 80-1100-3 7-49