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 The SGP-50 is a CO2 purifier device designed for use with the SNO GUNtm dry ice snow cleaning system. It's purpose is to take inexpensive low grade CO2 from a CO2 cylinder and convert it into ultra pure bone dry CO2 for use with the SNO GUNtm.





Although the SGP-50 is designed to operate at normal CO2 cylinder pressures of 800-1200 psi (depending on ambient temperature) it can not withstand the very high pressure of expanding liquid CO2 if cold liquid is trapped anywhere in the CO2 path and power to the unit is interrupted. Expansion of the cold liquid as it warms up can be sufficient to burst the rupture disc assembly inside the SGP-50. To prevent this from happening, the SGP-50 is designed without a power switch, to be run continuously. If it is desired to turn off power to the unit because you will not be using it for a few days, please do so in the manner indicated later in these instructions.






The SGP-50 should be connected to a non-siphon (vapor withdrawal) cylinder of CO2 so that it will be fed CO2 vapor and not CO2 liquid. Make this connection from the CO2 cylinder to the "INPUT" with the SG-6 six-foot CO2 hose provided. Connect the SNO GUNtm to the SGP-50 by attaching the female CGA-320 fitting at the end of the hose opposite the SNO GUNtm onto the adapter protruding out from the "OUTPUT" valve of the SGP-50.Use the Teflon washers provided to ensure a good seal. The orientation of the rupture disk assembly is not important.





When all connections have been made, open the valve on the CO2 cylinder thus allowing CO2 vapor to fill the hose to the SGP-50. If no leak is detected, open the "INPUT" valve on the SGP-50. After a few seconds, the SGP-50 will be full of CO2 vapor and the flow of CO2 should stop. If no leaks are present, open the "OUTPUT" valve on the SGP-50 to fill the SNO GUNtm hose with CO2 vapor. Once it is determined that no leaks are present in the system, plug the SGP-50 into a non-switched 115 VAC outlet and allow the unit to begin condensing the CO2 vapor into CO2 liquid. After about 15 minutes, the SGP-50 and the SNO GUNtm will be ready for use.






When the SNO GUNtm will not be used for some time, the SNO GUNtm and the SGP-50 should be drained of liquid CO2. It is not safe to leave CO2 under pressure in a hose that will be unattended. The proper procedure for draining the SGP-50 and the SNO GUNtm hose is to be sure the CO2 valves on the supply cylinder and the input and the output of the SGP-50 are open. Then remove electrical power from the SGP-50 so that it will not continue to cool the CO2.

Turn on the SNO GUNtm and allow the system to bleed until no dry ice snow is being formed at the SNO GUNtm tip and the frost has melted from the metal fittings of the SNO GUNtm rupture disk assembly. This may take 4 to 5 minutes. Close the CO2 valve on the supply cylinder and continue to bleed the system until the pressure gauge on the SGP-50 reads 200 to 300 psi. This may take 2 to 3 minutes. Close the input valve to the SGP-50. Close the output Valve on the SGP-50. Allow the SNO GUNtm assembly to bleed down completely and close the SNO GUNtm control valve. It is a good idea to keep a slight positive pressure in the SGP-50 so that contaminants do not enter the idle system. You may leave the system in this state for an indefinite period of time.





Insulating the hose to the SNO GUNtm will also help reduce the vapor accumulation. A split tubular insulation similar to the kind used to insulate home hot water pipes will work fine for this improvement.

Should you run out of snow, it is probably because you are trying too hard to clean a surface that may not be able to be cleaned by this method. The SGP-50 is not designed to keep up with a 100% duty cycle of the SNO GUNtm. It should however keep up with the normal intermittent usage of the SNO GUNtm. Short 5-second bursts are typical of this type of cleaning process as explained in the SNO GUNtm operating manual. Should you desire to operate more than one SNO GUNtm from a single Purifying device, please contact us with your specific requirements. We will be more than happy to quote a device to meet your specific requirements.

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