TM5-4120-375-144-7.SERVICE UPON RECEIPT CHECKLIST. (cont.)LOCATIONITEMACTIONb .Remove air filters and inspectthe filter for accumulation ofdirt.c .Clean filter.5.SideReturn Air Dampera.Check to see that the FRESH AIRcontrol moves freely between thethe MIN and MAX position and thatthe return air damper opens andcloses properly.b.Adjust or repair FRESH AIR controls.4-4