Disassemble tbe pressure cutout switches and housing as directed below: (See figure 5-6).
a. Remove four screws in the end of the housing, and remove both pressure cutout switches. Becareful to avoid
kinking the capillary tubes when removing them from the notches in the edge of the housing.
b. Pry off spring clip on end of pressure cut out switch, and remove the spring clip and the coverfrom the wire
connections. Disconnect wires as necessary.
Inspect the housing for physicaJ damage and deformation. Replace if necessary. Inspect the pressure cutout switches for
breakage or missing parts. Test the switches as follows:
u. Connect the high-pressure cutout switch to an ohmmeter, multirmeter or other continuity testing device.
Do not use compressed air for testing the pressure cut out switches. Oil, moisture and other impurities
could be carried into the refrigeration system.
b. Comect the capillary flare nut
to a cylinder
of dry nitrogen, and slowly pressurize the switch assembly.
c. When pressure gauge indicates 415 psig (29.17 kg/cm2)press and release reset button. Continuity should be
d. Continue the slow pressurization
of high-pressure cutout switch: When pressure reaches 460 10 psig
(32.34 0.7 kg/cm2), continuity should drop out.
e. Slowly reduce prssure to 415 10psig (29.17 0.7 kg/cm2) and press
f Connwt the low-pressure cutout switch to the continuity tester and the source of dry nitrogen, as directed in
steps a and b above.
g. Slowly pressurize the switch to 12 psig (0.9km/cm2) and press reset button. Continuity should be indicated.
to pressurize the switch
psig (29.17 km/cm2). Continuity should be indicated at all times.
Slowly reduce pressure. Continuity should drop out at 7 5 psig (0.5 0.35 kg/cm2).
If pressure-continuity requirements are not met, replace the pressure cutout switch.
Assemble the pressure cutout switch housing as follows:
a. Install a 7/16-inch grommet in the hole in one end of the housing. Cement in place. Pull two wire leads
through the hole in the grommet.
b. With terminal covers removed from both pressure cutout switches, connect the short wire from terminal 1 of
the high-pressure switch to terminal 2 of the low-pressure switch.
c. Connect wire leads to terminal 2 of the high-pressure switch and to terminal 1 of the low-pressure switch.
Tag the leads for identification. Install both terminal covers and retaining clips.
d. Install a split grommet on both capillary tubes, and insert the low-pressurecutout switch in the lowerpartof
the housing. Secure with two screws. Form the capillary tube along the back and comer of the housing to the left-hand
notch. Tag connecting end for identification.