How to Read an AO Smith Pool Motor Label

WRITTEN BY:  Matthew S.

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When the time comes to replace your pool pump motor the jumble of numbers and ratings on a motor can be overwhelming. This "How to" will guide you through which information is useful in your replacement pump motor search. We also provide tips on essential parts that should be replaced when installing a new pump motor.

Step by Step


Step 1

Tools you may need: 1. A cloth and cleaning solution, this is needed to remove any dirt or grime causing your pump motor label to be unreadable 2. A Shaft Seal or GOKIT when replacing your motor. Working seals and gaskets are vital to the health of your pool pump. A malfunctioning shaft seal will cause water from the pump to leak into your electrical motor causing it to fail prematurely. A GOKIT includes the complete set of your pumps gasket's and O-rings, including the shaft seal.

Step 2

In general there are two main labels on a pool pump; the pump label and pump motor label. Both can be used to determine the correct motor replacement but first we will focus on the motor label as it is the quickest and easiest to search. If your motor label is unreadable, later in the guide we will show you how to backtrack information off your pump to find the correct replacement. Quick Tip: The manufacturer of the pump motor and the pump itself are different companies even if the pump is brand new from the factory. For example, you have purchased a Hayward Super Pump, the wet end of pump where the water is housed is made by Hayward. The motor attached to that pump wet end was likely made by A.O. Smith, Century or Marathon.

Step 3

An A.O. Smith pump motor label has a lot of different numbers and ratings that can have an appearance of alphabet soup at first glance. Let's narrow down the scope to just the information we will need to search for a new pool pump motor replacement. The list is as follows: Motor Model Number, Horsepower (HP), Service Factor (SF) and Frame (FR)

Step 4

When reading an A.O. Smith pump motor label the most pertinent information to aid you in finding a replacement is the "Motor Model Number." With this information alone you could find the exact match. As shown in the picture, an A.O. Smith motor may have two model number formats listed, either one can be used in INYO's pool pump motor search engine.

Step 5

The first format is one that follows the line of "UST1102", "ST1102" or "SN1102". The set of letters in the beginning denote the service factor rating of the pump. The "UST-" stands for an uprated motor and "ST-" means it is a full rated. The last four digits show its HP: "-1102" = 1 HP, "-1152" = 1.5 HP, "-1202" = 2 HP and so on. Type complete number (ex. UST1102) into INYO's product search at the upper right-hand portion of our site to find pool pump motor match

Step 6

The second format of pump model numbers contains a prefix that is most commonly "C48", "C56", "K48" or "K56". This prefix is followed by four to nine letters and numbers which identify the specific motor. Type this entire number into INYO's product search to find the correct pump motor match. An example of this pump model number format: C48L2N134C1

Step 7

If the Motor's model number is unavailable then we will have to use a combination of the pump label information and other available info on the motor label. The information needed off the motor label is the Horsepower (HP), Service Factor (SF) and Frame (FR).

Step 8

In most cases the Pump's manufacture label is located near the outlet port, location may vary depending upon the maker.

Step 9

On the pool pump label there should be two numbers listed, the serial and model. The pump model number can be entered into our product search engine; the result should provide the make, model and horsepower. Copy down this information and enter our pump motors section by selecting it in our “Shop by Category” sidebar.

Step 10

In the Pump Motors section you will be asked for the manufacturer then the model. Your specific model may have two categories that list by your pump motor's service factor (SF). The motor's SF is listed on the label, this number will be in the range of 1.00 - 1.95. A SF of 1.00 to 1.27 is listed as an Up rated, anything over is Full rated. Please be sure you match the Service Factor of your pump as failure to do so will cause incompatibility between your current pump and new replacement motor.

Step 11

After checking all the previous information and have found a possible correct replacement, your last piece of info to check will be the Frame (FR). Most motors have a frame of "48Y", "56Y", "48J" or "56J". If your prospective replacement matches HP, SF, and FR then you have successfully found your motor replacement.


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Matthew  Posted: 08/03/2018 15:06 PM 

Hello Sung - the correct motor is the B2843. The correct part number is the 7-177452-03 The seals and the hardware pieces of the pump are matched to a pump housing instead of the motor. What is the model number of the pump housing this motor is bolting to?

Matthew  Posted: 08/03/2018 14:36 PM 

The correct part number begins with a 0 and not the letter O. If you use the 0, it should cross-reference the B854 1.5 HP Uprated

Cheryl  Posted: 08/02/2018 23:26 PM 

I have an AO Smith Century Centurion Part O-193993-05 1.5 HP y56y That I am trying to replace and cannot find the correct part. Could you please help me?

Sung  Posted: 07/31/2018 20:42 PM 

My old motor has the following inf. Cat. BZ01-05 Part 7-177452=03 Fr Y56Y Hp 2 HP and White All units are corroded, so I need a motor, steel plate , sealers and others.

Inyopools  Posted: 04/16/2018 14:02 PM  Inyo Product Specialist

Hello Robert - If the plastic components of the pump look good, I would suggest replacing the motor and seals. The replacement motor would be part number STS1102. The seal kit is GOKIT3. We carry the complete pump as well, model SP2607X102S.

robert taylor  Posted: 04/14/2018 13:01 PM 

I have a hot tub pump that was originally installed in 1983. This past summer the pump was making a considerable amount of noise (bearings?). Before starting the hot tub this spring, I believe I need to replace the pump given its age and potential chance of failure this summer. I have read the hoe to instructions included with this web site and I have found the following descriptions in the absence of a model number. The A.O. Smith motor has a SF=1.00, a FR=X56J, and Hp=1.5-0.25. The pump itself, which is a Hayward has an HD = SP2607X102S and an ID= 21120610004296017. I would appreciate information on a replacement pump as well as the cost. Finally, is it likely the motor that needs replacing. or the whole assembly (Smith plus Hayward)? Thank you.

Inyopools  Posted: 02/25/2018 10:21 AM  Inyo Product Specialist

David - Your housing can use several different manufactured motors, so knowing the motor model will not identify the pump housing. Try finding the part number of the strainer cover, usually stamped on the underside of the cover. Enter that number into our search field and that should link you to a parts list for your pump.

David  Posted: 02/21/2018 11:12 AM 

Need to replace a pump housing and seal kit. Do not have info on pump housing. Will info from motor be of any help to see what pump housing it is?

Inyopools  Posted: 02/20/2018 9:00 AM  Inyo Product Specialist

Martin Mayes - Unfortunately, we cannot identify a motor by its serial number. You would have to go to the manufacture for that. We would need the motor's model number(s). See Step #4 of this guide. If you have that number, try entering it into our search field.

Martin Mayes  Posted: 02/17/2018 23:02 PM 

i am trying to replace my spa pump. serial BZ03-10; PH 1; HZ 60 Volts 230; AMB 40 C; Code A; FR Y48Y; AMP 11.0/3.3

Inyopools  Posted: 01/29/2018 12:47 PM  Inyo Product Specialist

SCP - When replacing a motor, you want to look at the motor's Total HP which is the product of HP and Service Factor (SP)- stated on the label. Your current 2 speed has an upper HP of 2 and a SF of 1.35 which is a THP of 2.7. The direct replacement for your Tristar 2 speed is Motor, 2hp Full 2-speed Tristar 208/230v (spx3220z2ber). If you want to go to a single speed, the closest equivalent motor is A.O. Smith 2 H.P Square Flange Full Rate Motor - SQ1202. It's THP is 2HP x 1.3 SF or 2.6 THP.

SCP  Posted: 01/25/2018 19:09 PM 

I have a 2 speed Tristar SP3220Z2BE motor part# 7-K56AA15A04-05. it is a 2 speed motor 2hp/0.25. I have 2 questions. What is the correct replacement motor for that pump? Can I go with simply a 2hp replacement motor? If so what is that motor number?

Inyopools  Posted: 01/25/2018 17:39 PM  Inyo Product Specialist

Dan - Sorry, there are several .75 HP AO Smith motors that almost meet your specs. To make sure I select the right replacement motor, can you send me the mod numbers as described in step 3 above - like UST 1152 and C48L2N134C1?

Inyopools  Posted: 01/23/2018 23:07 PM  Inyo Product Specialist

Angela - Sorry, I cannot determine the make of your motor on serial number. And I did not get your picture attachment. Can you send me the mod numbers as described above - like UST 1152 and C48L2N134C1?

Inyopools  Posted: 01/23/2018 22:55 PM  Inyo Product Specialist

Anonymous (replacement motor) - The replacement motor for your current B853 motor is A.O. Smith 1 HP, 56Y Frame, Up-Rate Motor (B2853). Be sure to buy a GOKIT with it.

Dan  Posted: 01/20/2018 9:11 AM 

I need a replacement motor for: RPM: 3450, V 115, A 5.6, HZ 60, FR 48, Time Cont, Code C INS B, HSG O.D.P., Type F, PH 1, SFA, AMB 40 C, HP .75 SPD

Angela  Posted: 01/16/2018 17:58 PM 

Hi, Looking for a replacement pool pump motor and propeller for my Jacuzzi pool pump. Motor is an A.O. Smith 1.5 hp, Serial # BX7-22, FR P56J, Type CX. Picture of label is attached. Can you let me know of you have replacement motor and propeller?

Anonymous  Posted: 01/15/2018 11:44 AM 

need a replacement pool motor for AO Smith. Cat B853, Serial BW10-17, Part (from label) 7-177215-04. Any ideas?

Inyopools  Posted: 12/11/2017 13:10 PM  Inyo Product Specialist

richard brown - Unfortunately, we do not have a match for your motor based on the data supplied. It may be because this is an air compressor motor. Our data is related to pool motors.

richard brown  Posted: 12/05/2017 21:44 PM 


Inyopools  Posted: 11/22/2017 12:56 PM  Inyo Product Specialist

Jay - I'm not sure what your question is, but if you are asking for the link to a replacement motor, here is the link for an  A.O. Smith 1.5 HP, 56Y Frame, Up-Rate Motor (b2854),

Jay  Posted: 11/18/2017 7:42 AM 

I have to replace a A.O. Smith motor...CAT B2854 Ser 27013CH, Part 0-F56AA40A01-24, Type CX Frame Y56Y, HP 1.5 SF 1.10 PH 1, Hz 60 RPM 3450 Volts 230/115 Amps SF 8.0/16.0 Code J, 1081 Pool Pump , Duty Mount Horizontal with vent holes down

Inyopools  Posted: 11/12/2017 14:11 PM  Inyo Product Specialist

Frederick - We would have to have more information on the motor to be sure of its replacement. Can you provide the old motor's Model number, HP, SF, amps as they appear on the motor label.

Frederick  Posted: 10/31/2017 19:27 PM 

I have a burned out Emerson #1081 3/4 HP, is their a replacement for with tha-e same design.

Inyopools  Posted: 09/03/2017 13:38 PM  Inyo Product Specialist

Joe - See the response for "Anonymous" below. I assume you are the same person.

Inyopools  Posted: 09/03/2017 13:34 PM  Inyo Product Specialist

Anonymous (replacement motor) - The replacement for you 7-193992-06 motor is 3/4 HP Motor EE - Full Rate (B661, B2661).

Joe  Posted: 08/29/2017 13:49 PM 

I have a pump motor to replace, A.O.Smith 7-193992-06 FR=R56Y, what is the correct cross referenced pump motor.

Anonymous  Posted: 08/29/2017 13:40 PM 

I need to replace my pump motor..
A.O. Smith part 7-193992-06 FR R56Y Type CX Hz=60 RPM=3450 Volt= 208-230/115 Amp= SF 6.0-5.6/11.2 Time = CONT ENCL=DP
Any help would be appreciated, as this is the only info I can provide on the pump that shorted with white smoke coming out of it during the Harvey Hurricane. Thanks

Inyopools  Posted: 08/21/2017 11:39 AM  Inyo Product Specialist

Mark - Your replacement motor is a Century (A.O.Smith) 1.5 HP Motor EE Full Rate (B284). You should also replace the pump gaskets and shaft seal which is linked to your pump model. If your pump is a Pentair Whisperflo, you will need a GOKIT32 or GOKIT32Salt for salt water pools.

Mark  Posted: 08/19/2017 15:11 PM 

I need to replace my motor. A.o. Smith century centurion. 07-193994-06. Type CX. FR: Y56Y hz 60 volts 208-230. Amps Sf 9.6-8.8 1081 pool pump duty mount. The energy saving motor. Thank you

Inyopools  Posted: 08/07/2017 11:58 AM  Inyo Product Specialist

Harry - The replacement motor for your 7-193390-20 motor is 1 HP Single Speed Motor -BN25V1. Be sure to buy the gasket and seal kit. We would need to know the pump manf and model to specify this kit.

Inyopools  Posted: 08/07/2017 11:18 AM  Inyo Product Specialist

Ryan - If you can read the serial number on the motor or the pump, give Pentair a call at 800-831-7133. They may be able to identify the motor for you. Otherwise, give us a call at 407-834-2200 and speak to one of our service reps. We may be able to identify your motor with pictures or other available data.

Harry  Posted: 08/05/2017 17:54 PM 

I have an A.O. smith motor SP1510-z-1-xes. Its part# 7-193390-20. Serial BY04-21. Frame W48Y. Type SP. 115 volts. Code H. RPM 3450.
1HP. What motor do I need to replace it, and what is the cost.
Thanks for your time.

Inyopools  Posted: 08/05/2017 11:48 AM  Inyo Product Specialist

Joed - Did you mean Jandy instead of Mandy? And do you want to replace your pump or just the pump's motor? The specs you provided are for the motor. I would tentatively say your current motor is a 1.5 HP Motor EE Full Rate (B2842), but I would have to have more data on your motor to be sure. Is your motor an EE (Energy Efficient) motor with an HP of 1.5, an SF (Surface Factor) of 1.47 and amps of 9.6 - 8.8?

Ryan  Posted: 08/05/2017 11:44 AM 

My pump is a sta rite but the model number and code number are completely faded away. The model number has P2R printed on it but then nothing else is visible after that. I am trying to replace the motor, which I have found no problem, but i dont know if my pump is pre or post 1998 to buy the correct seal kit. What should i do?

Joed  Posted: 08/01/2017 17:30 PM 

Would you guys carry this type of pump and at what cost to me

I've a Mandy serial CB06-14
Part # 7-193994-06
Type CX. FR Y56Y. PH 1
60 hz. Rpm 3450 volts 208-230
1081 pool pump duty mount with vent holes down

Inyopools  Posted: 07/27/2017 17:19 PM  Inyo Product Specialist

mat- The duplicate replacement motor for your current s48c51z01 is a 1 HP Single Speed Motor - BN25V1.

mat  Posted: 07/25/2017 18:45 PM 

a.o.smith s48c51z01, that's the model which needs to this model still available for replacement or do I need to look for substitute replacement, which model would that be? Thanks

Inyopools  Posted: 07/24/2017 9:55 AM  Inyo Product Specialist

syed - The B654 would be the standard energy efficient replacement for the B128 motor. UCT1152 might also work but I'd like to know more about the pump model it is going into. I would recommend an EE motor for Dallas. And we do not get involved with installations so have no data on that process.

syed  Posted: 07/24/2017 5:52 AM 

My current motor specs are: Century Centurion AO Smith; CAT B128; SERIAL 13711CH; PART O-164303-23; TYPE CX; FRAME M56J; HP 1.0; SF 1.40; PH 1; HZ 60; RPM 3450; VOLTS 230/115; AMPS SF7.2/14.4; TIME CONT; ENCL DP; FORM KJM; CODE J; INSUL CLASS B; AMB 50 DEG C; 1081 POOL PUMP DUTY MOUNT HORIZ WITH VENT HOLES DOWN
The motor is making loud noise so I think it needs to be replaced immediately. I have found the 1 HP B128 Replacement Pool Motor on your website as the exact match and I understand I need to also get tune up kit GOKIT77 to do the job correctly. Before I order, I would like to confirm that this is the right replacement motor and tool kit. Also if I want to replace the motor with a different “energy Efficient” model then I have found that UCT1152 is the exact match for my current motor replacement…. So my question is first that if this is correct replacement and if so, would you recommend this change to energy efficient model for Dallas, TX area pool?
Also one last question… if I don’t want to do the replacement myself and after getting the motor have it locally installed…. What would be the reasonable estimated cost for such installation?