Emerson 3000 - Manual (Page 44)

Water-Cooled Models—Self-Contained Compressor
38
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 Standard 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 21 Johnson Controls valve adjustment
4.3.2 High Pressure Valve - 350 psig (2413 kPa) System for 3-Ton Units (Metrex Valve)
Adjustment
The valve may be adjusted using a 1/8" diameter rod. Turn the adjusting collar nut counterclockwise
to raise head pressure; turn it clockwise to lower head pressure. Rotation directions are viewed from
top of valve spring housing.
Range
spring
Valve spring
guide
Top
retainer
Range adjustment screw
Insert screwdrivers underneath
the valve spring guide