The present invention relates to a thermal event detection sensor (1) comprising at least one housing (20, 30, 40) in which is disposed at least one
printed circuit board (10, 12, 13, 14) having at least one sensing element (11), the housing (20) having an opening (21, 22) allowing a fluid to reach the sensing element (11) via a circulation conduit (50), the circulation conduit (50, 52) having at least one
system (51, 53) for circulating the fluid formed in the wall of the conduit (50). Fig. 2.