Combustion driven device featuring multi-chamber airflow

A gas combustion-powered apparatus has a first chamber (54), a rotatable fan (24) in the first chamber, an ignition source (12) in operable relationship to the first chamber to ignite a combustible gas, and a second chamber (58). A communication passage (22) is located downstream of the fan (24) between the first chamber (54) and the second chamber (58), and is constructed and arranged for enabling passage of an ignited gas jet from the first chamber to the second chamber. An intake port (40) is located on a wall of the first chamber (54) upstream of the fan (24), and a bypass port (52), separate from the communication passage (22), is located on the wall of the first chamber (54) downstream of the fan (24).