Water Cooled Models
4.3Water 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.
4.3.1Standard Valve - 150psig (1034kPa) System for 3 & 5 Ton Units (Johnson Controls Valve) High Pressure Valve - 350psig (2413kPa) System for 5 Ton Units (Johnson Controls Valve)
Adjustment
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
Range spring
Valve spring guide
Range adjustment screw
Top retainer
Insert screwdrivers underneath the valve spring guide
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 particles from the seat. If this fails, it will be necessary to disassemble the valve and clean the seat.
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