Manitowoc QD0202A, Service Manual

Page: 160 / 175

Refrigeration System Section 7
7-48
Part No. 80-1100-3
Self-Contained Charging Procedures
1. Be sure the toggle switch is in the OFF position.
Figure 7-15. Charging Connections
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.
Remove the hoses from the ice machine and install the
caps.
Important
The charge is critical on all Manitowoc ice
machines. Use a scale or a charging cylinder to
ensure the proper charge is installed.
MANIFOLD SET
CLOSED
FRONTSEATED
CHARGING
CYLINDER
VACUUM PUMP/
RECOVERY UNIT
OPEN
CLOSED
LOW SIDE
SERVICE
VALVE
HIGH SIDE
SERVICE
VALVE
BACKSEATED
OPEN
SV1404B