Casing of a heating, ventilation and/or air conditioning unit and shutter for such a casing

The invention concerns a damper (15) for a housing of a heating, ventilation and/or air conditioning unit which comprises a first and a second outlet channel, characterized in that the damper comprises a longitudinal shaft (16) of axis bearing at least two vanes (17 and 18) which extend radially and which bear at the level of two opposite edges, on the one hand, a first flap (20), parallel to the shaft (16), intended to at least partially obstruct a first outlet channel of said housing and, on the other hand, a second flap (21), parallel to the shaft, intended to at least partially obstruct a second outlet channel of said housing.