Brother HL-3040CN Service Manual page 294

(5) Remove the Ozone filter from the Air filter holder ASSY.
Ozone filter
(6) Release the five Hooks to remove the Air filter holder ASSY from the Lower air duct.
Note:
When removing the Air filter holder ASSY from the Lower air duct, be careful not to
damage the Toner filter.
Toner filter
Hook
Fig. 5-153
Hook
Lower air duct
Fig. 5-154
5-120
Air filter holder ASSY
Hook
Air filter holder ASSY
Confidential