The trigger is set to 13.8 and is fixed. This same PWM was tested on my vehicle and we had no problems. I will be contacting the manufacturer of the PWM as well so I can get ideas on that side as well. I still think it is something in this vehicles electrical system, but that is only a thought.
The cell is configured properly. This PWM has current limiting so we are able to up the catalyst, KOH, and lower the current. This gives us roughly .75 to 1 liter per minute gas output on a bench test.
Would there be a reason for this vehicle to keep a higher voltage while running and/or just after shutting the vehicle off? It just seems like we are getting voltages that are too high for our PWM to function with.