Manitowoc Q450 Service Technician's Handbook page 159

SELF-CONTAINED RECOVERY/EVACUATION
1. Place the toggle switch in the OFF position.
2. Install manifold gauges, charging cylinder/scale,
and recovery unit or two-stage vacuum pump.
LOW SIDE
SERVICE
VALVE
3. Open (backseat) the high and low side ice machine
service valves if required, and open high and low
side on manifold gauges.
4. Perform recovery or evacuation:
A. Recovery: Operate the recovery unit as directed
by the manufacturer's instructions.
B. Evacuation prior to recharging: Pull the system
down to 250 microns. Then, allow the pump to
run for an additional half hour. Turn off the pump
and perform a standing vacuum leak check.
5. Follow the Charging Procedures.
MANIFOLD SET
OPEN
BACKSEATED
CLOSED
RECOVERY/EVACUATION
CONNECTIONS
–149–
OPEN
BACKSEATED
HIGH SIDE
SERVICE
VALVE
OPEN
VACUUM PUMP/
RECOVERY UNIT