1-10
TM 3-4230-218-12&P
1-12. AIR SYSTEM PRINCIPLES OF OPERATION.
The air system consists of the axial vane fan enclosed in a shroud. When the
centrifugal clutch engages, the fan assists in drawing air from around the
engine cooling fins to cool the engine and provide preheated air to the heat
exchanger.
In the heat exchanger, the air is used for combustion which in
turn heats the water in the heating coil.
1-13.
WATER SYSTEM PRINCIPLES OF OPERATION.
The water system consists of an over-capacity, roller-type pump that is belt
driven by the engine through the centrifugal clutch. The pump can provide
varying flow rates at the water outlet and is controlled by a pressure regula-
tor valve on the control panel.
The water pressure regulator valve will allow
any over supply of water to be returned to the inlet side of the pump.
1-14. HEAT EXCHANGER SYSTEM PRINCIPLES OF OPERATION.
The heat exchanger system is a double-walled, convection type.
The func-
tional components consist of a burner and a heating coil.
The burner is fired
by an electronic ignition system through a spark plug.
Pressurized fuel is
received and atomized by the burner jet.
Air is received from the fan in the
burner, mixed with the atomized fuel and ignited.
The heated air is then
forced around the water coils to heat the water and then out through the
exhaust side of the heat exchanger.
1-15. ELECTRONIC CONTROL MODULE PRINCIPLES OF OPERATION.
Through the use of valves, switches, and thermostats, the electronic control
module does the following things:
a.
Monitors water pressure.
b.
Monitors water temperature.
c.
Monitors and controls burner ignition.
1-16.
ENGINE FUEL SYSTEM PRINCIPLES OF OPERATION.
Fuel is supplied to the engine from a five gallon (18.9 liter) fuel can.
The
ball pump is initially used to prime the fuel system.
Fuel is drawn through
the coarse fuel can filter and through the fuel inline filter prior to entering
the fuel pump and then the carburetor.
