Abstract: A multiple barrel forced-air heater comprising a base, a first heater jacket, and a second heater jacket. The base may comprise a fuel tank adapted to accept a fuel. The first heater jacket may comprise a first device for producing a first air flow, a first Venturi adapted to mix fuel with the first air flow to form a first fuel-air mixture, and a first combustion site adapted to combust the first fuel-air mixture to generate a first amount of heat and a first amount of combustion products. The second heater jacket may comprise a second device for producing a first air flow, a second Venturi adapted to mix fuel with the second air flow to form a second fuel-air mixture, and a second combustion site adapted to combust the second fuel-air mixture to generate a second amount of heat and a second amount of combustion products.