A filter housing adapted to be mounted in an air ventilation system, wherein the filter housing comprises: an upstream air entrance opening defined by an air entrance opening frame, a downstream air exit opening defined by an air exit opening frame and located opposite of the air entrance opening, a rear wall extending between and attached with the air entrance opening frame and the air exit opening frame, a front opening opposite to the rear wall, the front opening being defined by a front opening frame, and a cover sealing the front opening when the cover is closed; a movable filter holder arranged within the housing and arranged to receive a filter through the front opening; and two clamping mechanisms (15, 16) arranged at opposite first and second walls (11, 12) of the housing, which first and second walls extend between the air entrance opening frame and the air exit opening frame, each clamping mechanism being connected with the filter holder to clamp the filter in a clamped position; wherein each clamping mechanism comprises a release device (17, 18) engaged with the filter holder, and arranged for releasing the filter from the clamped position to a released position by moving the filter holder, which release device comprises a handle (19, 20) arranged at the front opening; wherein the release device comprises a centre rod, which is connected with the handle, which is axially movable, and which is rotatably connected with the front opening frame, and eccentric disks (29, 30), which are arranged on the centre rod, and which are rotatably connected with the filter holder; wherein each handle is arranged to be in a locked state when the filter is in the clamped position, arranged to be unlocked by being pulled out a distance to a pulled out and non-rotated position, and arranged to be rotated from the pulled out and non-rotated position to a release position in order to release the filter. an upstream air entrance opening defined by an air entrance opening frame, a downstream air exit opening defined by an air exit opening frame and located opposite of the air entrance opening, a rear wall extending between and attached with the air entrance opening frame and the air exit opening frame, a front opening opposite to the rear wall, the front opening being defined by a front opening frame, and a cover sealing the front opening when the cover is closed; a movable filter holder arranged within the housing and arranged to receive a filter through the front opening; and two clamping mechanisms (15, 16) arranged at opposite first and second walls (11, 12) of the housing, which first and second walls extend between the air entrance opening frame and the air exit opening frame, each clamping mechanism being connected with the filter holder to clamp the filter in a clamped position; wherein each clamping mechanism comprises a release device (17, 18) engaged with the filter holder, and arranged for releasing the filter from the clamped position to a released position by moving the filter holder, which release device comprises a handle (19, 20) arranged at the front opening; wherein the release device comprises a centre rod, which is connected with the handle, which is axially movable, and which is rotatably connected with the front opening frame, and eccentric disks (29, 30), which are arranged on the centre rod, and which are rotatably connected with the filter holder; wherein each handle is arranged to be in a locked state when the filter is in the clamped position, arranged to be unlocked by being pulled out a distance to a pulled out and non-rotated position, and arranged to be rotated from the pulled out and non-rotated position to a release position in order to release the filter.