Xylem P81547D Series 90 In-Line Centrifugal Pump - Manual (Page 19)

Maintenance
Disassembly
Disassembly precautions
WARNING:
• This manual clearly identifies accepted methods for disassembling units. These methods
must be adhered to. Trapped liquid can rapidly expand and result in a violent explosion
and injury. Never apply heat to impellers, propellers, or their retaining devices to aid in
their removal.
• Make sure that the pump is isolated from the system and that pressure is relieved before
you disassemble the pump, remove plugs, open vent or drain valves, or disconnect the
piping.
• Always disconnect and lock out power to the driver before you perform any installation
or maintenance tasks. Failure to disconnect and lock out driver power will result in
serious physical injury.
• Crush hazard. The unit and the components can be heavy. Use proper lifting methods
and wear steel-toed shoes at all times.
• After you disassemble a gasket joint, always use a new gasket upon reassembly. Never
reuse old gaskets. Failure to follow these instructions can result in serious personal
injury, death, and/or property damage.
NOTICE:
Make sure that all replacement parts are available before you disassemble the pump for
overhaul.
Drain the pump
CAUTION:
• Allow all system and pump components to cool before you handle them to prevent
physical injury.
1. Disconnect the electrical supply and lock it out of service.
2. Loosen the conduit box cover screws and remove the cover.
3. Disconnect the conduit and wiring.
4. Close the isolation valves on the suction and discharge sides of the pump.
You must drain the system if no valves are installed.
5. Open the drain valve.
Do not proceed until liquid stops coming out of the drain valve. If liquid continues to
flow from the drain valve, the isolation valves are not sealing properly and you must
repair them before you proceed.
6. Leave the drain valve open.
Do not close the drain valve until the reassembly is complete.
7. Drain the liquid from the piping and flush the pump if it is necessary.
8. Disconnect all auxiliary piping and tubing.
9. Loosen the volute capscrews but do not remove them.
10. Shift the pump position slightly in order to allow the pressurized water to escape.
Maintenance
18 Series 90 Installation, Operation, and Maintenance Manual