Did a thorough cleaning, tested ok. Used twice so far, for a couple of hours to chase the chill on a cool morning, and kicked on during the night by itself once last week. I shut it off before work, went to turn it back on yesterday, no feed, just a slight hum noise, no blinking lights. Emptied the hopper, pulled the small gear and chain, the large gear turns ok, figured motor's shot. Install new motor, same problem. Help! Just re-checked everything, also checked vacuum hose at the switch end. Where does the other end go? Am I missing something, or do I need a circuit board?