An installation for drying a web of non-woven material includes a fan (6), a heating oven (3), an outlet pipe (C2) which puts the outlet of the oven (3) in communication with the intake of the fan (6), a branch pipe (C3) branching from the inlet pipe (C1) upstream of the heat source (4) putting the pipe (C1) in communication with the inlet of a drying device (10, 11), a pipe (C4) for the extraction of air from the drying device (10, 11) and a humidity level probe (13) mounted in the extraction pipe (C4).