A.O. Smith Century Centurion Manual

A.O. Smith
531 North Fourth Street
Tipp City, OH 45371
937-667-2431 • Fax [phone]
www.aosmithmotors.com
Bulletin 2944
©A.O. Smith Corporation 2006 #2944 1/06

Installation
—
Maintenance
—
Service
—
Troubleshooting
CENTURY®
POOL & SPAMOTOR
MANUAL

1
Welcome to A.O. Smith’s line of Century®
Motors. This pocket manual is designed for
one purpose — to make it simple for you to
install, maintain and troubleshoot Century pool and
spa motors. Contrary to what you may be thinking just
now, your last name doesn’t have to be Edison in order to
properly service the motors shown in the following pages.
All you need are a few basic tools and some helpful hints;
the kind that appear throughout this
booklet.
We’ve included all the information we think you’ll
need to repair the most common pump motor problems
encountered out in the field. This easy to read manual con-
tains great illustrations and diagrams for quick
reference. Assisting your customers is your job. Helping
you do that with minimum delay is our job; that’s why
we’ve prepared this informative manual.
INTRODUCTION

2
Replacements for every brand. Every now and then
you probably come across a motor that’s beyond repair.
When you do, remember that A.O. Smith manufactures
replacement pool and spa motors for practically every
brand you’ll ever encounter in the field. So save yourself
some time and effort and just ask for Century first — at
any A.O. Smith distributor or dealer. Century motors are as
rugged as any you’ll find, but keep in mind that all motors
need service and maintenance at one time or another.
Safety first. Remember, before you begin to work on
any electrical appliance be sure to TURN OFF THE
POWER. The only time you’ll need the power on is
when you check motor voltage and amperage. If you over-
look this important guideline, someday you could unex-
pectedly get a real charge out of your work! Always play it
safe — double-check to be certain that the power is off
before you start to work on a pool or spa motor.
If you have any suggestions or would like more
information about a particular subject, please write
or call:
A.O. Smith
531 North Fourth Street
Tipp City, OH 45371
800-543-9450
www.aosmithmotors.com

3
Century Pump Motors ......................................................5
Design Features................................................................7
Nameplate Information....................................................9
Installation
Heat..........................................................................13
Moisture...................................................................14
Power Source ..........................................................14
Altitude.....................................................................14
Mounting..................................................................14
Electrical Connections .............................................15
Grounding................................................................15
Wire Size..................................................................15
Wire Selection Guide.....................................................16
Tools ................................................................................17
Maintenance
Moisture...................................................................17
Cooling.....................................................................18
Seasonal...................................................................18
Cleaning ...................................................................18
Lubrication...............................................................18
TABLE OF CONTENTS

4
Motor Troubleshooting
Motor Fails To Start (makes no sound)..................19
Motor Fails To Start (hums, tries to start,
blows fuse or trips breaker)....................................20
Motor Starts But Shuts Down
(overload problem)..................................................21
Noisy Motor.....................................................................21
Motor Hot, Smoking Or Cycling.....................................22
Information Needed For Motor Replacement ..............23
Troubleshooting A Capacitor .........................................23
Best Way To Use A Volt-Ammeter.................................24
How To Replace Bearings..............................................24
Service ............................................................................27
Wiring Diagrams’ Table of Contents.............................28
Wiring Diagrams.......................................................29-54
Date of Manufacture Table ............................................55

5
Centurion®, C-flange
Switchless “1081” Motor
• Standard Efficiency
• E-Plus, High Efficiency
• 1⁄2– 5 Hp
• No Switch, No Governor
• Single phase or three phase
• Suitable for operation at 50 Hz,
1.0 service factor
• Aluminum or cast iron NEMA “C” mounting brackets
• True NEMA 56-frame
• Keyed or threaded shaft
• UL standard “1081” approvable
• Full-rated and Up-rated
• 50° C Ambient
• Available as a Century two-speed motor
Centurion®SE, C-flange
Switchless “1081” Motor
• 1⁄2– 5 Hp
• Standard Efficiency
• Single phase
• Aluminum NEMA “C”
mounting brackets
• 50° C Ambient
• True NEMA 56-frame
• Keyed or threaded shaft
• UL Standard “1081” approvable
• Full-rated and Up-rated
• 303 stainless steel shaft
CENTURY® CENTURION &

6
Centurion®, Square Flange
Switchless “1081” Motor
• Standard Efficiency
• E-Plus, High Efficiency
• 1⁄2– 5 Hp
• No Switch, No Governor
• 303 stainless steel
threaded shaft
• Suitable for operation
at 50 Hz, 1.0 service factor
• Single or three phase
• True NEMA 56-frame
• UL standard “1081” approvable
• Full-rated and Up-rated
• 50° C Ambient
• Available as a
Century two-speed motor
Neptune®, C & Square Flange
• Standard Efficiency
• High Efficiency
• 1⁄2– 3 Hp
•Advanced Switch Technology
• 48 frame shell diameter
• 303 stainless steel threaded shaft
• UL standard “1081” approvable
• Full-rated and Up-rated
• 50° C Ambient
E-PLUS®MOTORS

7
Flex-48™ Single-Speed Motors, Thru-Bolt Mount
Suitable for jetted tubs and above-ground pools and spas.
• 1⁄2- 3 Hp
• 56-frame conversion base
• 3-1⁄2” shaft height
• 3⁄8” threaded shaft
• Auto-reset overload
protection
• 1.0 service factor
Flex-48™ Two-Speed Low Amp Start & Run Motors
For Spas and above-ground pools, thru-bolt mount.
• 3⁄4- 3 Hp
• 56-frame conversion base
• 3-1⁄2” shaft height
• 3⁄8” threaded shaft
• Auto-reset overload
protection
• 1.0 service factor
C
entury pool and spa pump motors are tailored for
demanding pool loads and environments. Check these
outstanding features:
1. Full-rated 56-Frame diameter gives greater thermal
capacity, better durability with industrial quality construction.
CENTURION®
DESIGN FEATURES
FLEX-48™
POOL AND SPA MOTORS

8
2. All Threaded shafts are 303 stainless steel for superior
corrosion resistance. Keyed shaft of carbon steel is iron
phosphate treated to prevent rust. Stainless steel shafts
provided on cast iron C-flange, keyed shaft product.
3. Double-sealed high thrust bearings protect against dirt and
moisture. Factory lubricated, never need regreasing.
4. Special aluminum alloy brackets or cast iron NEMA “C”
brackets resist corrosion from pool chemicals.
5. Drive-end bearing locked to limit shaft endplay.
6. Continuous rated run capacitor provides high running
efficiency and better starting performance in low voltage
situations.
7. Easy connect terminal board is designed with screw post
line terminals. All you need is a screwdriver for fast and
easy installation wiring.
8. Moisture resistant, Class B insulated windings for extra
protection against moisture, high ambient temperatures,
salt spray, chemicals, diatomaceous earth, sand, dirt,
insects, etc.
9. Motors designed to meet UL Standard #1081, protects
internal components from rain, dirt and chemicals.
10. Class B automatic reset overload protector suitable for
high ambient temperatures. Prevents nuisance tripping in
hot areas.
CENTURION®
DESIGN FEATURES