How do I vent a pellet stove?

Pellet stoves can be vented horizontally through a wall using a 3-inch diameter pellet vent, or vertically with a 3- or 4-inch vent if the vent length exceeds 15 feet. Pellet fireplace inserts use a 4-inch stainless steel chimney liner connected to the insert, topped with a chimney cap and top plate for proper exhaust.