TM9-4120-401-14
4-27.
POTENTIOMETER (TEMPERATURE CONTROL) (R1). - continued
b. Test.
(1) Using schematic diagram, check resistance across potentiometer TEMPERATURE control (6)
terminals. Resistance across terminals 2 and 3 should be 0 to 60 ohms when turned fully clockwise
WARM and 4500 to 5500 ohms when turned fully counterclockwise COOL.
(2) Replace potentiometer TEMPERATURE control (6) if it tests defective.
c. Replace.
(1) Loosen two setscrews holding knob (7) to potentiometer TEMPERATURE control (6). Remove knob.
(2) Remove nut (8), lock washer (9), and potentiometer TEMPERATURE control (6).
(3) Tag and unsolder leads from potentiometer TEMPERATURE control (6) terminals. Remove control.
(See paragraph 4-24.)
(4) Cut heat shrink tubing to approximately three-quarter inch (1.9 cm) long.
(5) Slip heat shrinkable tubing over leads.
(6) Solder leads in place on potentiometer TEMPERATURE control (6) terminals using tags and wiring
diagram (figure 4-6). (See paragraph 4-24.)
(7) Slip heat shrinkable tubing over solder connection and shrink in place.
(8) Remove tags.
(9) Install potentiometer TEMPERATURE control (6) into control panel (4) and secure with lock washer (9)
and nut (8).
(10) Adjust potentiometer TEMPERATURE control (6) shaft to midway point and install knob (7) pointing
midway on TEMPERATURE scale. Secure knob to shaft with setscrews.
(11)
Secure control panel (4) to box (5) using four sets of screws (1), lock washers (2), and flat washers (3).
d. Adjust.
Adjust potentiometer TEMPERATURE control (6) to desired setting.
NOTE
FOLLOW-ON MAINTENANCE:
Install control panel (para 4-25).
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