TM 9-4120-498-14
This task covers:
a. Test
b. Replacement
INITIAL SETUP
Tools
Equipment Condition
Tool kit, refrigeration SVC
Power OFF
Evaporator acess door open
General Safty Instructions
Evaporator access panel removed
WARNING
Voltages used can kill. Always disconnect power
card to air conditioner before performing any
internal maintenance. Shutting unit off at its
control panel does not disconnect unit power.
a. Test.
(1) Tag and disconnect wire leads.
(2) Check continuity between TB3 and leads. Repeat for all wire leads.
NOTE
Using the low range ohmmeter function of a multimeter, measure the heating element resistance.
(To avoid sneak circuit error, measure the resistance only with the heating element leads disconnected
from the remainder of the circuit). Normal resistance is 27 ohms. A meter reading of indicates an
open circuit.
(3) Replace heating element if no continuity is indicated.
b.
Removal.
(1) Remove the four screws (1) in the cover (2) on the heater end terminal box (3). Remove the cover (2).
(2) Remove the hex nut (4) from the defective heating element (5) threaded sleeve.
