Vogt Tube-Ice HFO10, Service Manual

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2-8
Charging Refrigeration Systems
Only technically qualified persons, experienced and knowledgeable in the handling of refrigerant
and operation of refrigeration systems, should perform the operations described in this manual.
All local, federal, and EPA regulations must be strictly adhered to when handling refrigerants. If a refrigeration
system is being charged from refrigerant cylinders, disconnect each cylinder when empty or when the system is
fully charged.
Included with the machine is the required charge of R513A refrigerant (approximately 470 lb [213 kg]), isolated
in the receiver. Before shipment of the machine, the compressor service valves and the stop valves in the
various lines to the condenser and receiver were closed. These valves are tagged with instructions to be opened
before start-up of the machine.
Before opening these valves, check all joints for leaks that may have developed during shipment. If no leaks are
present, a positive pressure should show on the suction and discharge pressure gauges. They should indicate a
pressure approximately equal to the ambient temperature, which can be found using the pressure
temperature chart.
A gauge should be installed in the charging line to indicate refrigerant cylinder pressure. The cylinder may be
considered empty of liquid refrigerant when the gauge pressure is 25 psig (1.7 bar) or less, and there is no frost
on the cylinder. Close the refrigerant charging valve and cylinder valve before disconnecting the cylinder. Loosen
the union in the refrigerant charging line carefully to avoid unnecessary release of refrigerant into the
atmosphere. Refer to local and national regulations.
Immediately close the system charging valve at the commencement of the defrost or thawing
cycle if a refrigerant cylinder is connected. Never leave a refrigerant cylinder connected to the system except
during charging operation. Failure to observe either of these precautions can result in transferring refrigerant
from the system to the refrigerant cylinder, over‐filling it, and possibly causing the cylinder to rupture because
of pressure from expansion of the liquid refrigerant.
It is not recommended that refrigerant be transferred from a refrigeration system directly into a
cylinder. If such a transfer is made, the refrigerant cylinder must be an approved, clean cylinder that is free of
any contaminants or foreign materials. The cylinder must be connected to an approved recovery mechanism
with a safety shutoff sensor to ensure that contents do not exceed the net weight specified by the cylinder
manufacturer or any applicable code requirements.