Frick TDSH 233 short

Hey did anybody here ever have the potentiometer shaft stop rotating when the slide valve moves? I manually forced the slide valve(with solenoids) and saw motor amps change, took off pot and spun shaft by hand! I installed unit brand new from Frick almost a year ago. Gonna open it up in the AM, I'll let you know what I find.

Maybe the guide pin fell out allowing the shaft to spin freely.

Brand new unit installed this past April. Guide pin worn and broken off. Helical groove worn to a knife edge. No explanation. New parts in, runs fine. Unit starts and stops twice a day, mostly loads up to 100% and stays there.