Procedures For Charging System With Head Pressure Control - Wine Guardian PRO Series Installation, Operation And Maintenance Manual

Procedures for Charging System with Head Pressure Control

NOTE: When charging any system with head pressure control the outdoor ambient
temperature must be known.
Charging of Systems with Head Pressure Control in ambients above 70 degrees F (After normal
evacuation procedures):
1. Connect refrigerant cylinder to a charging or gauge port on the receiver outlet valve.
2. Open the receiver valve approximately one-halfway (so receiver and liquid line are connected
to charging or gauge port).
3. Charge liquid refrigerant into the high side of the system. Weighing the charge is
recommended.
4. Remove the refrigerant drum and connect it to the suction side of the compressor.
5. Charge refrigerant vapor into the low side. Do not allow liquid refrigerant into the low side.
6. Start the system.
7. Observe sight glass (at receiver outlet) to see if system is filling with refrigerant for normal
refrigeration cycle.
BUBBLES IN THE SIGHT GLASS
8. If the Sight glass shows bubbles, more refrigerant may be required, while allowing sufficient
time for the refrigerant to stabilize and clear the Sight glass. Use supplied information on the
following pages for proper final charge.
Charging of Systems with Sporlan Head Pressure Control in ambient temperature below 70
degrees F (After normal evacuation procedures):
NOTE: When charging in ambient below 70 Deg. F the procedure is very critical. Be sure to
adhere to the following steps. Failure to do so will result in overcharging the system.
1. Follow instructions 1 through 7 above.
2. If the valve setting is correct for the system being charged, it is quite likely that some
refrigerant will be backed up into the condenser and the Sight glass will indicate bubbles in
the liquid line.
3. Add more refrigerant, while allowing sufficient time for the refrigerant to stabilize and clear
the Sight glass. Use supplied information on the following pages for proper final charge.
4. At this point the system is correctly charged for this type of head pressure control at the
ambient temperature that exists while the charging procedure is taking place.
5. If the system is designed to operate at ambient below the ambient that exits during charging,
additional charge may have to be added now.
Since good system performance during low ambient operation depends on proper refrigerant charge,
it is very important that this phase of the installation procedure be done carefully. Many times, poor
system performance will be due to too little or too much charge. And in many cases, this will be the
last item suspected.
CAUTION
CAN BE CAUSED BY FLASHING DUE TO PRESSURE DROP FROM PIPE
OR ACCESSORY LOSSES, ETC.
42