I have a quadrafire cb1200. It will run fine for random amounts of time then shut down. The machine is completely clean. Pipes are clean. It works great, then when I'm at work or asleep It shuts down. The red light is on. There are pellets in the pot. Plenty of pellets in the stove. I come back and hit reset after removing the unburnt pellets and it fires up without any issue. Then after a few hours it dies again. It has been going on for a few days. Any help would be great