Pump Motor Replacement

[James1040]

I have a Century SN1152 motor that just quit. Will a Century B2854 replace it?
The schematic on my old motor said 1.5 hp, but it had a separate sticker that said Total HP = 2.4. I am not sure about the conflicting numbers.

 

[PointeTaken]

Your total HP is 2.4, and your “nameplate” HP is 1.5. Is there something on your nameplate that says something like “1.6 SF” or “Service Factor 1.6” or similar?

The history behind this convention of rating pumps (called uprating) is complex, but largely irrelevant in most applications. You just want to be sure you’re comparing apples to apples, in this case Total Horsepower. You should aim for a replacement motor with the same THP or even a little higher if you feel you need it and your system can handle it.

 

[PointeTaken]

I see two issues with your proposed replacement:

1. The SN1152 is specified for a 56J frame, while the B2854 is specified for a 56Y frame. The two are not, to my knowledge, interchangeable.
2. Even if the above problem didn’t exist, the B2854 has a THP of 1.65. That would likely not be enough for your pump, your system, and pool volume. Unless of course you were already running hot.

Note: if you do decide to change HP (either up or down) on your pump, it will likely necessitate a replacement of your impeller to one that is an appropriate size.

 

[James1040]

Thank you so much. At least now I know what to look for. 2.5 hp and 56J. I really appreciate you sharing your expertise.

 

[setsailsoon]

James,

There should be an identification plate on the motor. Take a photo of this and post it here. We can help better with that. Or just call a pool supply online companies such as Inyo pools. Have you considered switching to a variable speed pump? This would be a good time to do it.

Chris

 

[PointeTaken]

Have you considered switching to a variable speed pump? This would be a good time to do it.

Good call out! That’s exactly what I did when my old single speed bit the dust.

 

[James1040]

James,

There should be an identification plate on the motor. Take a photo of this and post it here. We can help better with that. Or just call a pool supply online companies such as Inyo pools. Have you considered switching to a variable speed pump? This would be a good time to do it.

Chris

What are the advantages of a variable speed pump? What should I look for as far as specs? This is awesome that so many knowledgeable people are willing to help the rest of us. Thank you

 

[setsailsoon]

Variable speed pumps allow you to run at much reduced power consumption by reducing the motor speed. They are mandated for new installations and the extra cost pays out in most locations in less than 2 years. Please fill in the signature for your pool. It helps experts get advice to you quicker and also helps them be efficient with their volunteer time. Here's how. For your existing single stage motor here are the important things to get quoted:

• Total HP which in your case is 1.5X1.6 or 2.4 THP
• Frame size Y56J, this ensures the bolts line up properly for your pump and the face plate is oriented properly

There are more details available than this but this info is all you really need. I'd call a couple of online motor suppliers and pool stores to shop around for the best price. If your pump is less than 10 years old I would get just the motor. For many pumps older than this you may find an expensive part like the housing will crack and it may just be better to bite the bullet with a new pump. There are exceptions depending on the original quality and Pentair pumps are known to have been very high quality.

Just to add another level of complexity you can in most cases change the pump motor to a 3rd party variable speed motor and this can be a great solution. If you ever plan to change to a salt pool this would definitely be a good time to go to variable speed either with a new pump complete or a variable speed motor. We really need more details about your pool to help much more. So please do get that signature going.

I hope this helps.

Chris

 

[James1040]

Thank you for your input, Chris and Pointe Taken. I was finally able to diagnose my problem and it turned out that it was only the capacitor. The main pump motor is running properly now. BUT, that led to another problem. My whole system was down almost a month while I was dealing with the main pump motor. Once I was able to get that running properly, it seems that the booster pump does not want to work properly.

When I turned it on, the motor did not sound normal. At first glance, it seemed the polaris 280 was working as it moved from the shallow to the deem end. When I realized it was not working, I took the coupling off where the cleaner connects to the plumbing at the wall. There was very low water pressure, about the equivalent of a water hose, no where near enough pressure to operate the cleaner. I did take the plug out of the booster pump while the main pump was running. There was water moving through the pump but again, not high pressure. About what you would get if you put a nozzle on a garden hose. The booster pump also got very hot to the touch while running.