Figure 6-22. Vapor-type burner.
b. Operation. To operate the burner, the valve that controls the flow of fuel is
opened to allow a small amount of fuel to run out through the holes in the bottom pipe.
This fuel, when ignited, heats the upper pipe and starts the fuel-heat-gas pressure cycle
(1) A properly operated burner will produce a blue flame. A yellow flame
indicates incomplete burning; this is caused by too much fuel escaping from the holes
and may be corrected by lowering the pressure in the line, either by reducing the size of
the holes or by lowering the rate of the flow. If the flame is blue but tends to blow itself
out, it indicates that the flow is too small. To correct this condition, increase the rate of
flow in the line, either by enlarging the holes or by increasing pressure in the line.
(2) The pressure in the line is increased by raising--and decreased by
lowering--the fuel container. A section of oil drum may be placed around the water
container to direct the flame for better heating.
c. Precautions. The fuel reservoir must, of course, be elevated several feet
above burners in order to supply adequate pressure and must not be allowed to
become empty because flame from burners could flash back into the reservoir and
cause an explosion.