Hello, re. the above furnace, when thermostat calls for heat, the "glow plugs" light up, burners ignite, then go out. This has been ongoing, and, until now, I have "gotten around this" by just leaving the blower on continually. However, even now, that seems to not do the trick! Any help is most appreciated.
If it were a dirty "flame sensor", I do not have a pilot light (electronic ignition), and per NorthernHeat's (fabulous!) pictures, I do not see anything at all like that-- each of the 6 burners appear identical, i.e. with no "extra" part, such as a sensor.
Also, if it is of any significance, 'last year' when I had this problem, the indicator light blinked
2 time; today it is blinking just 'once'... constantly.
Thanks much.
Again, any help is most appreciated.

Look for the flame sensor on the blower door inside diagram. There has to be some kind of proving switch/sensor for the safety control.