Did the home owner remove the pressure switch? I can't believe a tech would do that.
"The bitterness of poor quality remains long after the sweetness of low price is forgotten". --Benjamin Franklin
"Don't argue with an idiot, they will drag you down to their level and beat you with experience". --Mark Twain http://www.campbellmechanical.com
How does this even work? Doesn't the logic in most systems check to see that pressure switches are open at the beginning a cycle and then closed after at some point after the inducer is energized???
You're giving these units too much credit, they aren't that smart.
If I'm remembering correctly this unit has an ignition box that only cares about flame signal and closed safeties, if it's getting the 24v to the box it's good, so let the removal and jumping out begin!