8
D.
Ruptured pumping diaphragm—
If rupture is severe and pump is injecting into pressure, solution
leak will be obvious through the 3/16” (5 mm) diameter hole at the bottom of the spacer directly
behind the pump head. Replace pumping Liquifram™ (diaphragm). If rupture is a small pin hole,
there may be oozing of solution through the 3/16” (5 mm) diameter hole described above. Replace
ment of pumping Liquifram™ (diaphragm) will be necessary.
E.
Clogged Liquid End—
will cause low pump output. Purge Liquid End. Disassemble Liquid End.
Clean individual parts with water and detergent or appropriate cleaning solution.
F.
Injection into excessive pressure—
If discharge pressure is within 25 psi (1.7 Bar)* of maximum
pump rating, remove spring in injection check valve, if so supplied.
* 10 psi (0.7 Bar) for Series E74.
2.2 EXCESSIVE PUMP OUTPUT
A.
Syphoning
—If your Series E pump has a Liquid End other than a high viscosity LE, its injection
check valve assembly has a chemically resistant anti-syphon spring. Disassemble the injection
check valve and check to be sure this spring is in place and undamaged. Replace if necessary.
Note that the anti-syphon spring must be removed if injection is into a pressure within 25 psi (1.7
Bar)* of pump’s maximum pressure rating. Liquid Ends with a suffix “S” have, in addition, a dia-
phragm type anti-syphon valve, which prevents syphoning and over pumping.
* 10 psi (0.7 Bar) for Series E74.
B.
Incorrect knob settings
—Check stroke length knob (lower knob) by rotating it counter-clockwise
to zero position. The Liquifram™ (pumping diaphragm) should stop reciprocating. If it does not,
reset knob and continue counter-clockwise rotation until motion stops. Reset knob by grasping the
knob and pulling it towards you. Pry the yellow cap off of the knob. Place the knob on a flat surface.
Using needle nose pliers, squeeze the inner section together while lifting the outer section up (see
Figure 5). Push the inner section back onto the “D” shaped stroke shaft. With the pump running,
zero the pump by turning the inner section of the knob counter-clockwise . Position the outer
section of the knob so that the pointer aligns with zero (0) on the nameplate. Push down on the
outer section of the knob (a snap sound will indicate that parts are locked together). Replace the
yellow cap over the outer section of the knob, aligning the tabs on the cap with the slots on the
knob.
2.3 ChANGING PUMPING LIQUIFRAM™ (DIAPhRAGM)
A.
Make sure size code marking (0.9 S.I., 1.8 S.I. or 3.0 S.I.) on spacer and Liquifram™ (diaphragm)
are the same. Liquifram™ and spacer size code must match in order for the pump to function. The
E74 Liquifram™size code is 6.0 S.I., (spacer is 3.0 S.I., but there is a large black spacer adapter).
Always wear protective clothing, gloves and face shield when working on or near chemical metering
pumps.
B.
Depressurize discharge line following steps outlined on the supplement “Liquid Handling
Assembly Instructions”. Lift foot valve from solution and let pump run pumping air for a few minutes.
Then remove pump head.
C.
Set stroke length knob (lower knob) to zero, rotate it counter-clockwise with the pump running,
then stop the pump by turning stroke frequency knob (upper knob) to “off”.
D.
Lift edge of Liquifram™ and rotate it counter-clockwise to unscrew the Liquifram™.
E.
Before installing new pumping Liquifram™, turn pump on and rotate stroke length control knob
(lower knob) to the proper setting per the following table:
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