What is a Pellet Stove?

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 storage container (hopper) into a burn-pot area, they create a constant flame that requires little to no physical adjustments.

A pellet stove normally consists of these components, whether basic or complex:

  • A hopper (stores pellets)
  • An auger system (feeds pellets to burn pot)
  • Two blowers (combustion and convection)
  • A firebox or combustion chamber (where the fire burns)
  • Various safety features (thermodisc and air switch)
  • A main control panel/board

To properly function, a pellet stove uses electricity and can be plugged into a normal wall outlet. A pellet stove, like an automatic coal stoker, is a consistent heater consuming fuel that is fed evenly from a refillable hopper into the burn-pot (a perforated cast-iron basin), through a motorized system. The most commonly used distributor is an auger system that consists of a spiral length of metal encased in a tube. This mechanism is either located above the burn-pot or slightly beneath and guides a portion of pellet fuel from the hopper upwards until it falls into the burn-pot and begins to combust.

Fan systems are necessary for clean, economical performance.  The flame produced is concentrated and intense as a combustion blower introduces air into the bottom of the burn pot.  While some pellet stoves will be hot to the touch (especially on the viewing window), most manufacturers utilize a series of heat exchangers that run along the back and top areas of the visible firebox.  With a convection blower, room air is circulated through the heat exchangers and directed into the living space.  This method allows for a much higher efficiency than the radiant heat of a hand-fed wood or coal stove.  Along with convection air, an exhaust fan forces air from the firebox through special venting specifically made for pellet fuel.  This cycle of circulation is an integral part of the combustion system as well, for the concentrated high-temperature flame will quickly overheat the firebox.  The possible problems associated with overheating are electrical component failure and flames traveling into the auger tube potentially causing a hopper fire.  As safeguards, all pellet stoves are equipped with heat sensors enabling the controller to shutdown if any unsafe conditions are exceeded.

Pellet stoves can either be lit manually or through an automatic igniter. The igniter piece resembles a car's electric cigarette lighter heating coil. Most models have automatic ignition and can be readily equipped with thermostats or remote controls.

A Corn Stove is designed for whole kernel shelled corn combustion and is similar to a pellet stove.  The main difference between a pellet stove and a dedicated Corn Stove is the addition of a metal stirring rod within the burn pot.  These vary in design, but usually consist of one long metal stalk with smaller rods welded at a perpendicular angle in order to churn the burn pot as it spins.  During a normal burn cycle the sugar content within corn (and other similar bio-fuels) will cause the ashes to stick together forming a hard mass known as clinkers.  The metal stirring rod will break apart these clinkers causing a much more consistent burn.

Article taken from wikipedia.org - http://en.wikipedia.org/wiki/Pellet_stove