Manitowoc J250 Service Manual page 150

Section 7
.
Self-Contained Charging Procedures
Important
The charge is critical on all Manitowoc ice
machines. Use a scale or a charging cylinder to
ensure the proper charge is installed.
1. Be sure the toggle switch is in the OFF position.
MANIFOLD SET
CLOSED
FRONTSEATED
LOW SIDE
SERVICE
VALVE
CHARGING
CYLINDER
OPEN
Charging Connections
OPEN
BACKSEATED
HIGH SIDE
SERVICE
VALVE
VACUUM PUMP/
RECOVERY UNIT
CLOSED
SV1404B
Refrigeration System
2. Close the vacuum pump valve, the low side
service valve, and the low side manifold gauge
valve.
3. Open the high side manifold gauge valve, and
backseat the high side service valve.
4. Open the charging cylinder and add the proper
refrigerant charge (shown on nameplate) through
the discharge service valve.
5. Let the system "settle" for 2 to 3 minutes.
6. Place the toggle switch in the ICE position.
7. Close the high side on the manifold gauge set.
Add any remaining vapor charge through the
suction service valve (if necessary).
NOTE: Manifold gauges must be removed properly to
ensure that no refrigerant contamination or loss
occurs.
8. Make sure that all of the vapor in the charging
hoses is drawn into the ice machine before
disconnecting the charging hoses.
A. Run the ice machine in freeze cycle.
B. Close the high side service valve at the ice
machine.
C. Open the low side service valve at the ice
machine.
D. Open the high and low side valves on the
manifold gauge set. Any refrigerant in the
lines will be pulled into the low side of the
system.
E. Allow the pressures to equalize while the ice
machine is in the freeze cycle.
F. Close the low side service valve at the ice
machine.
G. Remove the hoses from the ice machine and
install the caps.
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