Replacing 2-Speed Pump for Single-Speed

[covkid]

I need to replace the (very noisy, about to seize-up) motor on my Pentair Whisperflo 2HP 2-Speed Pump (Model #WFDS-8, Part #011523).

I very rarely use the low-speed mode because it doesn't generate enough pressure to push around the Jandy Ray-Vac cleaner when the Solar heating is also running (which is just about all the time). The regular 2HP speed mode is plenty adequate for both.

I'm looking at just replacing the motor with an equivalent 2HP SINGLE-Speed motor, like a "Century USQ2012 2HP", an "A.O. Smith-Century B2748 2 HP" or an "Emerson Motors EUSQ2012", etc., but I keep running into something about "48Y Frame" and "Y56Y" Frame. What is this? How do I know they'll fit my existing housing and bolt placements? And Impeller? What else do I need to know??

P.S. I do, at least, know I need a Square Flange and also I'll need a new Shaft Seal.

If anyone can advise me, I'd be most grateful, because (being old, retired, grumpy and cheap) I'd hate to spend $400+ on a new 2-speed when I can do the job for half the price with a Single-Speed.

Thanks so much!

 

[JamesW]

In CA, the pump has to be less than 1 hp or two speed or variable speed. You can probably do what you want with a simple 1/2 hp single speed whisperflo.

 

[mas985]

CA regs are only an issue if you have someone else do it. If you replace the motor yourself, you can do what ever you want although I would still get a two speed motor and just figure out how to run on low speed. With a spa, you probably don't want to downsize.

I'd hate to spend $400+ on a new 2-speed when I can do the job for half the price with a Single-Speed.

If you can figure out how to use the low speed most of the time, you can easily make up the price difference plus some over the life of the motor. It might just be a valve setting issue. Post a picture of your equipment pad and a description of the plumbing layout, maybe we can figure out a way to do it.

 

[JamesW]

If the pump is more than 7 years old, it's likely to need a new impeller and seal plate as these tend to fail after about 7 years. If the pump is over 7 years old, it's typically better to replace it.

Low speed does not do well in high head applications. Low speed tops out at about 23 feet of head. If you're using solar and using a pump driven vacuum simultaneously, you need more than 23 feet of head.

The 1/2 hp meets regulations and should work. The regulations apply to all cases. There is no exemption for DIY.

Another option would be a variable speed pump. Since you have Jandy Automation, a Jandy VSP should work for you.

 

[mas985]

A 1/2 hp won't work for the spa!

And the regulations are not enforced for. DIY.

 

[JamesW]

A 1/2 hp won't power spa jets. It depends on how important it is to have strong spa jets. Perhaps the 2 hp waterfall pump could be valved as a dual purpose pump to work the waterfall or jets.

 

[mas985]

That could work but you would lose the spa and waterfall together and you would need to share the filter and heater.

 

[covkid]

That could work but you would lose the spa and waterfall together and you would need to share the filter and heater.

Thanks, guys, for the continuing advice, caveats and recommendations! I certainly hadn't appreciated there were so many options and different things to consider. And the CA rules just complicate things further.

I guess it's now up to me to make a decision, so I'll go away, consult with the boss and get my instructions as to what to do. (No doubt what she told me to do in the first place. Usually works that way!)

Thanks again!

- - - Updated - - -

Thanks, guys, for the continuing advice, caveats and recommendations! I certainly hadn't appreciated there were so many options and different things to consider. And the CA rules just complicate things further.

I guess it's now up to me to make a decision, so I'll go away, consult with the boss and get my instructions as to what to do. (No doubt what she told me to do in the first place. Usually works that way!)

Thanks again!