V46 and V47 Repair Parts and Service Instructions
2
Adjustments
To raise the valve opening point on direct-acting valves, turn the adjusting screw counterclockwise. To lower the
valve opening point, turn the range adjusting screw clockwise. See Figure 2. The closing point of the valve is not
adjustable. Pressure-actuated valves close approximately 3 to 7 psi (21 to 48 kPa) below the opening point, and
temperature-actuated valves close approximately 3 to 5°F (1.7 to 2.8°C) below the opening point.
If the compressor operates in high ambient temperatures, head pressures may remain high enough during off
cycles to prevent the valve from closing completely. In such instances, the opening point of the valve should be
raised just enough to cause the valve to close during compressor standby periods. The opening of the valve raises
the throttling point.
The all-range pressure-actuated valve settings can be adjusted for both low pressure refrigerant ranges of R-134a
and higher pressure refrigerant ranges of
R-22 (R-502).
Manual Flushing
To clear any sediment that may accumulate, valves may be manually flushed by inserting screwdrivers under both
sides of the main spring and lifting upwards to flush the valve. Manual flushing does not affect valve adjustments.
Inspection and Service
To inspect and replace internal parts, follow the procedures in this section.
After long periods of operation, the valve seat and rubber disc may become worn, pitted, or wiredrawn, preventing
the valve from completely closing off, allowing leakage through the valve in the closed position, when the pressure
and temperature is below the setpoint.
Shut off the liquid supply and relieve pressure in the line before servicing the valve. Contents of liquid lines could
be under pressure and the release of liquid under pressure may cause severe personal injury.
Figure 1: Manual Flushing
