3-5.1 Air/Electronic Maintenance
Maintenance of the A/E transducer may be required if there is extreme difficulty in setup or erratic
readings on the Trendsetter™.
Mag & Zero Needle Valves
If oil is present, it is helpful to clean out each needle valve. With the gage set on a master, unscrew
the mag knob (M) and remove. Allow the air to blow freely. Inspect the “O” ring on the needle valve
body: replace if necessary. Reinsert the mag needle valve and screw down until the point on the
Trendsetter™ scale comes back to the master point. Repeat the procedure on the zero knob. By
only cleaning one needle at a time, the gage setting is not lost. Re-check the mastering points
before gaging.
Bias Restriction
Remove bias bleed screw and metallic filter. Insert #1/4-28 screw into dropping resistor and pull out
restrictor assembly. Remove bottom metallic filter. Wash out in cleaning spirits. The dropping resis-
tor holes may be cleaned out (very carefully) with a sharp toothpick if necessary. Blow dry from
central hole in restrictor assembly, and reinsert components in reverse order.
When an extremely dirty air condition is encountered, it may be necessary to remove the needle
valve assembly and clean it. Unscrew the set screw holding the valve assembly. Pull out the com-
plete valve assembly. Unscrew the needle body, clean and inspect the “O” ring. Check the “O” ring
on the outer valve body and also at the bottom of the bore in the aluminum restriction block. If they
have deteriorated, replace.
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