The auger, which is basically a long screw, delivers pellets to the burn pot based on the speed dictated by the unit’s thermostat. Heat then carries through the home via convection (air driven) means, thus allowing air flow and a blend of warm and cool air to maintain steady, even burn temperatures.
A heat exchanger separates the smoke fumes from the warm air, thereby warming the room without smoking everyone out.
Pellet grills normally have a drip plate under the main cooking surface that allows fat drippings to flow into a catch vessel – normally a pail of some sort.
Because the heat and air flow is so well-regulated in Pellet grills, you can pack it with meat and literally walk away – being assured of steady temps and very predictable outcomes.
If you live in an area where wood furnaces are used (not like down here in FL where a few heat strips will do the trick), you may also be familiar with pellet furnaces.
Dating back to the early 1980s, Joe Traeger’s company first experimented with using wood pellets as fuel for a BBQ smoker as an offshoot of the home heating furnaces he was selling locally that used pellets.
Backyard “at home” BBQ smokers appreciate this feature when cooking things like chicken, which normally isn’t trimmed down as much as competition cooks might leave it.
Speaking of competition cooks, you’ll find that many competition BBQ pitmasters who use Pellet grills as their primary means of cooking are among the more well rested come Saturday.
Yes, some pellet grills use thicker metal, have better thermostats, air flow, racks, drip flow, etc.
But the ask any professional BBQ cooker who uses a pellet grill, and they’ll tell you that the quality of your smoke really does come down to the pellets themselves.