For several years now I've been heating my house with a DIY gravity fed pellet stove made out of a woodstove. The only part thats different is the door so it can be easily converted back. Here I explain the concept behind gravity fed pellet stoves and their short comings.

How do they work?

Basically the hopper feeds into a angled shoot. At the bottom of the shoot is a wire mesh basket that holds the pellets as they burn. when the embers and ash are soft enough they fall through the baskets mesh and fresh pellets slide down into the basket due to gravity and the cycle repeats, the fire doesn't go up the feed tube because air comes from a separate tube and meets the pellets on a angled burner plate. After hours of running a ridge of ash can form right on top of the burner plate. this can start to obstruct the pellets, so it needs cleaning occasionally.