TM 9-4120-402-14
5-25. HIGH PRESSURE SWITCH (S5). - continued.
a.
Test
(1)
Carefully pull pressure switch bracket (1) far enough out of unit to gain access to terminals.
(2)
Remove clip-on cover from high pressure switch (2).
(3)
Press and release the reset button to be sure switch is not tripped.
(4)
Use a continuity tester or multimeter to check for continuity between terminals 1 and 2 on switch. If
there is continuity, the switch is properly closed. If no continuity is found, switch must be replaced.
b.
Replace.
(1)
Tag and disconnect wire leads from high pressure switch (2).
(2)
Remove two sets of screws (3) and lock washers (4).
(3)
Discharge and purge the refrigerant system. (See paragraph 5-11 and 5-12.)
(4)
Debraze capillary tube (5) from discharge service valve line. (See paragraph 5-13.)
(5)
Remove high pressure switch (2) from unit.
(6)
Carefully run high pressure switch capillary tube (5) through unit to discharge service valve line.
(7)
Braze capillary tube (5) to fitting on discharge service valve line. (See paragraph 5-13.)
(8)
Position high pressure switch (2) onto pressure switch bracket (1) and secure with two sets of screws
(3) and lock washers (4).
(9)
Using tags and wiring diagram (figure 4-10) connect wire leads to high pressure switch (2) terminal.
Remove tags.
(10) Carefully coil excess capillary tubing in unit and tape in place to eliminate vibration.
(11) Carefully push pressure switch bracket (1) back into unit.
NOTE
FOLLOW-ON MAINTENANCE:
Install new refrigerant desiccant dehydrator (para 5-21).
Install rear panel (para 4-22).
5-65
