TM 10-4520-262-12&P 0002 00
0002 00-4
BURNER ASSEMBLY (1). The burner assembly (1) consists of a vaporization type burner. The burner
assembly uses a glow plug (2) for starting and requires no power other than the combustion blower (3)
and the fuel pump (4) to operate. During starting, an ignition pack (5) provides approximately 24 volts to
the glow plug to improve cold weather performance. An external fuel drain (6) is also provided on the
burner assembly to facilitate draining the fuel system.
HEATER CONTROL ASSEMBLY (7). The heater control assembly (7) uses information from the heater’s
sensors and the tent control assembly to determine the ideal firing rate. The air/fuel ratio is adjusted as
needed to maintain the ideal firing rate.
The heater control assembly (7) is located on the inside lower housing opposite the battery compartment
and is clearly marked. The heater control assembly controls all electrical functions, including system
startup, shutdown, and safety checks. It includes temperature and tilt sensors and the control circuit. The
control circuit analyzes information from the sensors to maintain the optimum firing rate for the heater. To
maintain the firing rate, it controls the rates of fuel flow and air flow, and continuously monitors the in-tent
control assembly settings to verify that the desired settings are reached.
The control system also controls system startup and shutdown, and monitors the heater safety systems. If
a fault is detected, it immediately begins the shutdown procedure and signals the operator that a fault has
occurred.
COMBUSTION AIR BLOWER (3). The combustion air blower assembly (3) integrates a 12-volt direct
current (DC) combustion air fan (8). It is located in the lower heater housing directly below the control
cable electrical connector and is clearly marked. The combustion air blower (3) draws air through the
combustion air inlet (9) and passes it through flexible hoses (10) to the burner assembly (1).
HEATED AIR BLOWER ASSEMBLY (11). A heated air blower assembly (11) is mounted under the duct
adapter (12). It features a 12-volt DC fan in series at the inlet end of the heater. The fan moves
approximately 250 cubic feet per minute (CFM) of heated, breathable air when operating.
The heated air blower assembly (11) forces fresh air or air removed from the tent through the heater. This
air passes across the TEG and the heat exchanger, where it absorbs heat and is directed into the tent.
Since the heater is designed to provide a variable British Thermal Units per hour (BTU/HR) output and
still maintain internal generation of system and battery electricity, the heater needs to regulate between
being a heater and being a generator of electricity as operational requirements change. This electronic
marriage of components allows for a safe and smooth transition from generation of electricity to heating.
The selection of a sophisticated controller reduces the amount of training required to operate the heater
and provides continuous monitoring and control of the heater.
FUEL PUMP (4). The fuel pump (4) is controlled by frequency pulses from the heater control assembly
and is responsible for supplying fuel in a vaporized state to the burner assembly.
HEAT EXCHANGER (13). The heat exchanger (13) transfers heat from hot gases produced by the
burner to the heated (breathable) air. The heat exchanger is sandwiched between the upper housing
assembly and the lower housing assembly. The heat exchanger provides an outlet and mounting flange
for the combustion exhaust pipe (14) and an O-ring seal and gasket (15). This heated (breathable) air is
then used to heat the tent. The heated air runs over the outside of the heat exchanger to collect the heat.
The hot gases, or combustion fumes, inside the heat exchanger are exhausted outside the enclosure
throughout the combustion exhaust pipe (14).
THERMOELECTRIC GENERATOR (16). The thermoelectric generator (TEG) (16) provides heater
system operating and battery recharging electrical power. Once the TEG is operating at full power, it
supplies enough energy to operate the heater assembly and maintain a battery charging voltage of 14.5
