TM 5-4520-241-14
CHAPTER 8
REPAIR OF ELECTRICAL COMPONENTS
8-1.
DESCRIPTION.
a. Wiring Harness. The wiring harness connects the heater's operating circuits to the control circuits at the mating
control box wiring harness. It also contains the power receptacle with built-in radio interference suppressor and the fuel
pump power receptacle.
b. Combustion Motor. The combustion motor supplies air to the burner head to provide efficient combustion.
c. Ventilating Motor. The ventilating motor blows air across the heat exchanger to supply warm ventilating air to the
enclosure. It may also operate as a cooling fan when the heater is in the FAN mode.
d. Fuel Pump Power Supply. The fuel pump power supply rectifies 120 VAC Line current to 24 VDC to operate the
solenoid valve on the carburetor and the remote fuel pump.
8-2.
WIRING HARNESS.
a. Disassembly.
WARNING
This space heater contains dangerous voltages which can cause severe electrical
shock. Be sure to disconnect the power plug before repairing the heater.
(1) Remove hardware (2, 3, and 4, fig. 8-1) to remove the female receptacle (1).
(2) Remove hardware (5, 6, and 7) to remove filter and receptacle assembly (8).
(3) Remove hardware (9, 10, 11, and 12) to remove fuel pump receptacle (13).
(4) Remove the threaded back on the fuel pump receptacle and unsolder the green lead (14) and yellow lead
(15). The bullet terminal on the yellow lead can be pulled out of the three-way electrical connector.
(5) Unsolder the black lead (16), green lead (17), and white lead (18) from the power receptacle. Do not remove
these leads from the female receptacle.
8-1
