Carrier BT30RF- EXPR Service & Installation Manual page 42

Install hand valves at the process stub ends. Hand
valves will be less restrictive to flow because of a larger
opening. They will also be easier to use during repair
procedures.
EVACUATION
Once the system has been cleaned and components
have been replaced, you are ready to initiate the final
servicing procedures necessary to achieve proper cabi-
net operation. Drier should be replaced prior to system
processing.
Pull an evacuation to approximately 50 microns.
CHARGING
You should use a charging cylinder to measure in the
correct amount of refrigerant.The charging methods are:
1. Add the refrigerant to the system until you reach a
balanced pressure. This will give you an approxi-
mate static charge.
MAINTENANCE & REPAIR
2. Weigh in the refrigerant using a scale calibrated in
ounces.
The cabinet's operation is now ready to be tested. A
final check of the refrigeration lines should be made
before running the cabinet.
Be sure the refrigeration lines are not kinked or rub-
bing against each other.
Also check that the door seals properly. An air leak will
affect proper operation, and the cabinet's ability to
reach its coldest temperature.
Run the cabinet at both 100% run, and a cycling tem-
perature for at least 24 hours. If the temperature and
pressures are correct, the system can be considered
repaired.
Hermetic systems should now have their process
stubs pinched off, hand valves removed and the ends
brazed shut.
41