28
4.0 MAINTENANCE
4.1 Diaphragm
Replacement
Disconnect AC power to the pump and disconnect the suction tubing, discharge
tubing, and air vent tubing. Remove the four head bolts with a 4mm or 5mm hex
wrench. Turn the stroke length knob fully counter-clockwise. Unscrew the
diaphragm and remove its retainer (small disk behind the diaphragm).
CAUTION:
There may be small brass spacers between the retainer and the
armature shaft. These spacers need to be reused when replacing the
diaphragm.
Install the new retainer and diaphragm on the shaft. Turn the
diaphragm clockwise until it bottoms on the shaft. Replace the pump head and
tighten the head bolts to a torque of 19 lb-in (2.16 N-m).
4.2 Valve
Replacement
Remove the suction and discharge tubing making sure discharge side has been
depressurized. Remove the suction fitting, two valve cartridges, o-ring and
gasket(s). Install the new o-ring, gasket(s) and valve cartridges. Be sure both
valve seats are in the same orientation. Refer to Figure below. Tighten the
suction fitting. Similarly remove and replace the discharge valve cartridges, o-
ring and gasket(s). For a more detailed drawing, refer to the Section 6.0.
4.3 Tubing
Check ends of tubing for splits, cracks, or thin spots. Examine the full length of
tubing for damage due to chafing, abrasion, stress cracks, excessive temperature
or exposure to ultraviolet light (direct sunlight or mercury vapor lamps). If any
signs of deterioration exist, replace the entire length of tubing. It is a good idea
to replace discharge tubing on a regular preventive maintenance schedule every
12 months.
CAUTION:
Before working on the pump, disconnect the power cord, depressurize
the discharge tubing and drain or flush any residual liquid from the pump head and
valves. Always wear protective gear when working around chemicals.
FLOW
VALVE CARTRIDGE ORIENTATION
GASKET
VALVE GUIDE
BALL
VALVE SEAT
Valve Cartridge Orientation
CAUTION:
There are many
small parts in the liquid end.
These parts must be installed
correctly for proper operation
of the pump
.
Summary of Contents for EH Series
Page 46: ...Notes...
