a. Assembly and charge the air conditioner in accordance with the following procedure:
b. Position the pressure cutout switch housing properly, and secure with four screws.
a new filter-drier, and
complete the assembly
of the air conditioner
in paragraph 5.55.
5.62. Description (See figure 5-8).
The pressure regulating valve is functionally apart of the bypass circuit, and opens when suction pressure drops below a
preset level. When the valve opens, it bypasses refrigerant gas to the suction side of the compressor to prevent the
formation of low suction pressures. If pressure testing indicates that the suction pressure is out of limits, adjustment of the
pressure regulating valve will usually correct the trouble. The pressure regulating valve is located in the top of the air
conditioner, in front of the pressure equalizer solenoid and liquid quench expansion valves.
In order to adjust or to replace the pressure regulating valve, gain access to it as described below:
a. Remove 18 screws and washers from the four sides of the fabric cover, and remove the cover.
b. Remove 15 screws and packing washers from the top surface of the top panel, and five screws from the rear
flange. Remove the top panel.
c. Remove five screws from the fresh air screen, and remove the screen.
visually inspect the pressure regulating valve for physical damage. Test for proper operation of the valve by pressure
testing the system in accordance with paragraph 5.27. If minimum suction pressure is out of limits, adjust the pressure
Adjust the valve by removing the knurled screw-cap from the top of the pressure regulating valve, and adjusting the
internal screw while observing the suction line gauge. Turning adjustment clockwise raises the suction pressure. When
the gauge indicates the proper suction pressure, replace the knurled screw-cap snugly on the valve.
All refrigerant gas must be discharged from the system before removing the valve.
While discharging the system, you can remove additional panels and grilles, junction box and control panel
assembly, which provide access to the filter-drier.
b. Remove the air intake grille by turning six cam-lock studs clockwise. Remove the air filter by removing two
screws in retainer and pulling out the filter.
c. Unscrew two panel fastener screws in the upper edge of the lower panel, and remove the panel.