TM 9-4110-255-14
4-30. REMOTE BULB THERMOSTAT S2 TESTING AND REPLACEMENT.
This task covers:
a. Testing
b. Removal
c. Installation
INITIAL SETUP
Materials/ Parts:
Equipment Conditions:
Lock Washers (2) (Control Panel)
Refrigeration unit shut down (para 2-7) and battery
1, Appendix G
disconnected (para 4-35).
Lock Washers (2) (Bulb Bracket)
Control box cover door raised and latched.
1, Appendix G
Left side condenser door open.
Self Locking Nut
Evaporator cover panel removed (para 4-15).
4, Appendix G
General Safety Instructions:
Self Locking Nuts (4) (Thermostat)
6, Appendix G
WARNING
Self Locking Nuts (2) (Thermostat Bracket)
6, Appendix G
Exposed rotating parts are used in the
Self Locking Nuts (4) (Dummy Stowage Connector)
refrigeration unit. Personal injury can result if
6, Appendix G
battery is connected.
Tie Down Straps
5, Appendix E
Marker tags (2)
4, Appendix E
Silicone RTV
1, Appendix E
a. Testing. (See Figure 1-4.)
(1) Be sure battery has been disconnected then remove two bolts (1) and lock washers (2). Open control
panel (3). Discard lock washers.
(2) Remove screw (4) and cover (5).
(3) Remove two bolts (6), lock washers (7), flat washers (8) and sensing bulb bracket (9). Discard lock
washers.
(4) Remove self locking nut (10), bolt (11), and sensing bulb bracket (9). Discard self locking nut.
(5) Remove clamp (12).
(6) Immerse sensing bulb (13) into a temperature controlled bath at 32F (0C). A bath at this temperature
can be made by putting the sensing bulb into a container of ice and covering with water. Ice must remain
packed around sensing bulb at all times during test.
(7) Using multimeter set to measure continuity, check remote bulb thermostat (14) continuity between
terminals 1 and 3 with thermostat setting at 24 F and at 40 F (-4 C and 4 C ). Continuity should be
indicated only when the setting is at 24 F (-4 C). If continuity was indicated at 40 F (4 C) setting,
replace thermostat.
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