Balance Pressure - Brooks Polycold MaxCool Series Installation And Operation Manual

Polycold Cryochiller
Installation and Operation Manual
The tubing for the refrigerant lines and cryocoil must be dried prior to installation.
• Perform strength test with dry compressed nitrogen using the appropriate
safety precautions
• After testing, backfill with dry nitrogen and cap the assembly.
• Hydrostatic pressure testing is NOT recommended because it introduces sig-
nificant amounts of water and will void the warranty.
• Lines or coils that are hydrostatically tested must be drained of water and then
baking out at 80 C for at least 12 hours under a dry nitrogen purge.
• A calibrated hygrometer should be used to verify that water vapor concentra-
tion is less than 50 ppm at the end of the bake out process.

Balance Pressure

Table 3-10: .Balance Pressures for Polycold Cryochiller Refrigeration Units
Refrigeration Unit
MaxCool 4000H
MaxCool 2500L
1
NOTE: These pressures are for the refrigeration units only. The balance pressure may drop 5-20
psig (35-70 kPa) after installing the refrigerant line and cryosurface and opening the isola-
tion valves.
2
NOTE: Balance Pressure refers to the pressure of the unit when it is turned off and warmed up
to room temperature. It is the balance of pressure on both sides, the suction side and the
discharge side, of the compressor. When the compressor is running, the unit creates a
pressure difference between the suction and discharge sides of the compressor.
Brooks Automation
214072 Revision B
Specifications and Site Preparation
NOTICE
Balance Pressure kPa (psig)
1241-1586 (180-230)
1448-1724 (210-250)
Cryocoils and Refrigerant Lines
1
3-11