RETURN AIR LOUVER AND AIR FILTER.-Continued

TM5-4120-383-14

4-13.

RETURN AIR LOUVER AND AIR FILTER.-Continued

(3) Agitate until dirt is removed, using a soft brush if

necessary to loosen caked-on dirt.

(4) Rinse in clear water or clean dry cleaning solvent.

(5) Drain, then hold filter horizontal and tap each edge on

bench or floor to dislodge droplets.

(6) Be sure filter is totally dry prior to installation.

Inspect.

(1) Check the louver for general condition. Bent louvers can

usually be straightened with the fingers. Refer further repair or

replacement to direct support.

Perforations or punctures in

(2) Inspect filter for damage.

screen and aluminum foil mesh can permit passage of unfiltered air.

(3) Inspect for packed or crushed mesh material obstructing

airflow through filter.

(4) Check for deformation of the frame. Straighten if

possible without crushing mesh material.

(5) Replace filter if crushed, punctured, badly deformed, or

broken.

Servicing.

(1) Louvers. Apply a few drops of light oil to all pivot

points and bearing surfaces of louvers. Wipe or blot up all excess

oil with a cloth.

(2) Filter. Apply coater (Item 1, Section II, Appendix E) to

the media in the filter element. Let dry and wipe off excess

coater.

Installation.

(1) Air flow arrows should point away from louver.

(2) Place filter in retainer clips.

(3) Secure louver with screws and lock washers.

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