A pellet stove is a stove that burns compressed wood or biomass pellets to create a source of heat for residential and sometimes industrial spaces. By slowly feeding fuel from a hopper into a burn-pot area, they create a constant flame that requires little to no physical adjustments. Pellet stoves can be vented on any outside wall without a vertical termination, into an existing flue or through the roof.   Most of these stoves have automatic ignition, ash pans and can be operated by a wall thermostat.