Figure 71.11. Space heater flow diagram.

Figure 71.11. Space heater flow diagram.

the liquid heater system. Refer to paragraph 151 for

system. Each system consists of a blower motor, fan,

details.

and the necessary air passages.

a. Fresh Air System. To circulate fresh air for

161. Electrical System

heating and distribution to the compartment, the fresh

air fan draws air through the opening at the rear of the

heater. The fresh air passes over and cools the motors,

The space heater is similar to the liquid heater

then passes around the burner unit and through a

electrical system described in paragraph 152 with the

passageway between the combustion chamber and the

exceptions of the pump switch and personnel heater and

inner wall of a secondary heat exchanger. It also

defroster switch which are omitted and the variations in

passes between the heater outer casing and the outer

the internal wiring (fig. 71.12 for the wiring diagram).

wall of the heat exchanger.

b. Combustion Air System. Air for the combustion

162. Motor-Generator Set

chamber enters the heater through the larger opening in

(fig. 71.13).

the heater base, passes through the combustion air

blower shell and into the burner. The air mixes with the

A 115 volt ac electric motor coupled to a 24 volt dc

fuel vapor in the burner, and combustion occurs.

generator provides an electrical source to maintain the

Contaminated combustion air passes through parts at

vehicle storage batteries at full charge while operating

the far end of the combustion chamber, into the

the winterization kit with the truck engine at rest.

secondary heat exchanger, and leaves the heater

Facility electrical source to operate the motor is

through the centrally located exhaust opening.

connected to the vehicle by a 50-foot cable. The

generator is protected from damage caused by

160. Fuel System

excessive current draw by a 30 amp circuit breaker. A

reverse current relay prevents current draw from the

battery when the electric motor is not operating.

The fuel system for the space heater is identical to

AGO 5667A