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Maintenance
CAUTION
●
Before working on the pump, disconnect the power cord, depressurize the discharge
tubing and drain or flush any residual liquid for the pump head and valves.
1. Diaphragm Replacement
Remove the power cord from the electrical outlet and disconnect the suction tubing, discharge tubing, and
air vent tubing. Remove the four head bolts with a 4mm or 5mm hex wrench. Unscrew the diaphragm and
remove its retainer (small disk behind 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 2.16/2.55 N•m.
2.16N•m (B11•16•21, C16•21)
2.55N•m (B31, C31•36)
2. Valve Replacement
Remove the suction and discharge tubing. Remove the suction fitting, the valve ass'y (consists of 2 × valve
ball, 2 × valve seat, 2 × valve guide, 1 × gasket & 1 × O ring). Install the new valve ass'y. Be sure both valve
seats are in the same orientation. Refer to Figure 5, below. Tighten the suction fitting. Similarly remove and
replace the discharge valve ass'y.
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 vapour 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 schedule every 12 months.
Figure 5
Valve Ass'y Orientation
Gasket
Valve Guide
Ball
Valve Seat
FLOW