Liebert Challenger ITR - Manual (Page 32)

Water-Cooled Models
26
4.3 Water 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.
4.3.1 Water Regulating Valve Adjustment
The Liebert Challenger ITR may be equipped with either a standard Johnson Controls valve, 150 psig
(1034 kPa) or with a high-pressure Johnson Controls valve, 350 psig (2413 kPa).
The valve may be adjusted with a standard refrigeration service valve wrench or screw driver.
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 13 Johnson Controls valve adjustment
4.3.2 Water Regulating Valve Manual Flushing
The valve may be flushed by inserting screwdrivers or similar tools under the opposing sides of the
main spring and lifting. This action will open the valve seat and flush any dirt particles from the seat.
If this fails, the valve must be disassembled for cleaning the seat.
4.3.3 Testing Valve Function
When the refrigeration system has been off for 10-15 minutes, the water flow should stop.
Should the water continue to flow, the valve is either improperly adjusted or the pressure sensing
capillary is not properly connected to the condenser.
Range
spring
Valve spring
guide
Top
retainer
Range adjustment screw
Insert screwdrivers underneath
the valve spring guide