Liebert CHALLENGER 3000 - Manual (Page 57)

Component Operation and Maintenance
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6.4.7 Water/Glycol Cooled Condensers
Coaxial Condenser
Each water or glycol cooled module has a coaxial condenser which consists of a steel outside tube and
a copper inside tube.
Coaxial condensers do not normally require maintenance or replacement if the water supply is clean.
If your system operates at high head pressure with reduced capacity, and all other causes have been
eliminated, the coaxial condenser may be obstructed and needs to be replaced.
Regulating Valve
The water regulating valve automatically regulates the amount of fluid necessary to remove the heat
from the refrigeration system, permitting more fluid to flow when load conditions are high and less
fluid to flow when load conditions are low. The valve consists of a brass body, balance spring, valve
seat, valve disc holders, capillary tube to discharge pressure, and adjusting screw.
Standard Valve - 150 psig (1034 kPa) system for 3 & 5 ton units (Johnson Controls Valve)
High Pressure Valve - 350 psig (2413 kPa) system for 5 ton units (Johnson Controls Valve)
Adjustment—The valve may be adjusted with a standard refrigeration service valve wrench or
screw driver. Refer to Table 19 for recommended refrigerant pressures.
To lower the head pressure setting, turn the square adjusting screw clockwise until the high pressure
gauge indicates the desired setting.
To raise the head pressure setting, turn the adjusting screw counterclockwise until the desired set-
ting is obtained.
Figure 10 Johnson Controls valve adjustment
Manual Flushing—The valve may be flushed by inserting a screwdriver or similar tool under the
two sides of the main spring and lifting. This action will open the valve seat and flush any dirt parti-
cles from the seat. If this fails, it will be necessary to disassemble the valve and clean the seat.
Range
Spring
Valve
Spring
Guide
Top
Retainer
Range Adjustment Screw
Insert screwdrivers under
the valve spring guide.