Maintenance
17
AVOID CONTAMINATION.
Follow the charging and venting procedure to
prevent reversed flow of system gas. Do not charge through the supply
coupling. Do not vent through the return coupling. Reversed flow can
contaminate the system with compressor oil.
NOTE
Adapter fittings for charging and venting are available as optional service tools.
See the Parts section of this manual.
Charging Procedure
PRESERVE YOUR WARRANTY.
Specifications require the use of 99.999%
pure helium gas. Using a lesser quality of helium can damage the system and
void the warranty.
AVOID A MALFUNCTION.
Repeatedly charging the system with helium gas
rather than locating and repairing gas leaks can cause a malfunction. Impurities
are introduced at an abnormal rate and can freeze in the shield cooler.
To charge helium gas to the system:
1.
Stop the compressor.
2.
Locate charge and vent tool, P/N 267191A, and bleed adapter, P/N 267192A. Screw
bleed adapter into charge and vent tool.
3.
Connect the charge line from the pressure regulator of a helium gas cylinder containing
99.999% pure helium with a dew point less than -62° C (-80° F) at 20.7
bar (300 psig) to Swagelok connector on charge and vent tool, P/N 267191A.
4.
Slightly open charge and vent tool's valve and thoroughly purge the charge line from the
regulator. It is important to remove all air contaminants to prevent them from
entering the system.
5.
Unscrew the self-sealing coupling on the bleed adapter, P/N 267192A, from the
charge and vent tool, P/N 267191A. Close the valve.
6.
Use two wrenches to attach the charge and vent tool to the 4M Aeroquip helium
charge port on the front of the compressor.
7.
Adjust the regulator to the required equalization pressure. See the Specifications section in
the F-70 Operating Manual.
Slowly
open the valve on the charge and
vent tool. Charge the system with helium gas to the equalization pressure.
8.
Close the valves on the charge and vent tool and on the gas cylinder.
9.
Disconnect the charge line from the charge and vent tool. Using two wrenches,
remove the charge and vent tool. Store the charge line to keep it clean.
Summary of Contents for F-70H
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Page 40: ...Troubleshooting 36 Figure 4 F 70H Compressor Wiring Diagram...
Page 41: ...Troubleshooting 37 Figure 5 F 70H Compressor Wiring Schematic...
Page 42: ...Troubleshooting 38 Figure 6 F 70L Compressor Wiring Diagram...
Page 43: ...Troubleshooting 39 Figure 7 F 70L Compressor Wiring Schematic...
