I’ve covered pellet-fueled boiler applications in several past issues of PME. All of them have involved hydronic distribution systems. While such applications are certainly the prevailing way pellet boilers are used, they are not the only option. It’s possible to couple a pellet boiler to a forced air distribution system.
Most of these applications will be retrofits — perhaps a way to transition a central forced air system away from fossil fuel and onto renewable wood pellets. The economics of such a conversion are increasingly attractive as fossil fuel prices soar.