WP440L-Series Reverse Osmosis System
Installation Instructions and User Manual
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Pump Maintenance (for systems with Sta-Rite Pump)
WARNING: Hazardous Voltage. Can shock, burn or cause death. Disconnect power to the pump
before servicing.
Tools required:
•
7/16" open end wrench (2 required)
•
Flat blade screwdriver with insulated handle
•
Work bench with vise recommended
•
Pliers or similar tool
•
Pipe wrench.
Impeller Stack Change Out
Remove pump from service and mount vertically in vise (if available) motor side down. Hold at center of motor. It may be
desirable to wrap motor with a shop rag to protect outside surface. Proceed as follows:
1. Attach pipe wrench to flats on discharge connection and turn clockwise to remove (left hand threads).
2. Remove screws holding motor canopy and remove canopy. Pull straight off as shown. Leave switch wires attached (if
present).
WARNING: Capacitor voltage may be hazardous. To discharge capacitor, hold insulated handle
screwdriver by the handle and short capacitor terminals together. Do not touch metal
screwdriver blade or capacitor terminals.
3. Unscrew the overload and move it aside. Do not disconnect wires. Slide 7/16" open end wrench in behind spring-
loaded centrifugal switch as shown. Place on motor shaft flats to hold shaft stationary.
4. With one 7/16" wrench in place on motor shaft, place second wrench on shaft hex at pump end and unscrew impeller
stack by turning counter-clockwise.
5. Once loose from motor shaft, hold shaft by snap ring using a pliers or similar tool, and pull stack from shell. You may
have to apply a back-and-forth motion to break stack loose from shell.
To assemble with replacement impeller stack, keep pump in the vertical position, motor down, and reverse instructions 1
through 5.
Assembly hints:
•
Apply a soapy water solution to suction and discharge O-Rings to ease seating of shell.
•
Make sure mechanical shaft seal spring is in proper position on motor shaft.
On three-phase models, apply Loctite No. 271 to motor shaft threads before reinstalling stack.
Illustration 16 - Impeller Stack and Mechanical Seal Changeout
