Thanks, it's been an interesting project.
I like to tinker with electronics.
The two thermocouples in the stack - one feeds a PID controller running in manual mode, moreless a basic temp controller, it's purpose is to shut the combustion blower off and close the damper if flue temps are less than X degrees (probably 150-200*F?). The blower will not continue to run in the fire burns out. The other goes to a display in the living room so at a quick glance I can see what is going on. Also, should I want to tinker this controller can shut off the combustion blower if temps reach X degrees while leaving the damper open. Not sure if it will be of any benefit, but at the least, neat to see what's going on.
In the first pic, the PID controller and one-shot timer can be seen mounted in an enclosure. When it's time to reload push the black button, damper closes, blower shuts off, and the timer begins to count down from preset time. If needed, add more time by pushing button again, walk away when finished, it will turn itself back on.
Everything gets an override switch as we know how reliable electronics are.