New Impeller?

cowboycasey

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Jul 3, 2013
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I just changed my Pentair 342002 1 HP pump to a new V Green 1.65 HP VS pump, everything went great until I read a thread to update the impeller to the correct size for the new motor.. I did all this yesterday so no issues taking it back apart and replacing an impeller...

This is where I am stuck.. Is my old motor up rated? I think it is...

Do I need to upgrade to this impeller or is this the impeller I have now, it is a 1hp full rated and 1.5 hp up rated? Pentair Impeller, 1.0 FR/1.5 UP - 355074 - INYOPools.com

or do I need to go to a VS impeller like this one that is 1.5 hp full and 2 hp up rated? Pentair Impeller, 35-5086 Pac Fab (355086) - INYOPools.com

If I do have to get a new impeller will I also need a new diffuser?

Or am I good to go :)
 

cowboycasey

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so I finally found the information and they are both the same motors with the same specs measured a different way... why do they do that???

Pentair 342002 1 HP, 1.25 SF
Century V Green .75 HP, 1.67 SF

So I think these are the same when it comes down to it.... When I max out the V Green it is at 16.2 PSI on my gauge and my old motor was about 16.4, I say pretty close :)

I have to run at 1350 rpm / 3.5 psi to use my SWG as 1100 is just a little low to cover the entire cell with water...
 

setsailsoon

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Not sure if you have the same motor as me but mine's THP is 1.65 (see below). If you have this motor you can go up to the next larger impeller. I did this and it works great but on my Jandy FHPM I had to go to the larger diffuser also. Let's me also run at lower speeds.

Chris

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JamesW

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Mar 2, 2011
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Do I need to upgrade to this impeller or is this the impeller I have now, it is a 1hp full rated and 1.5 hp up rated? Pentair Impeller, 1.0 FR/1.5 UP - 355074 - INYOPools.com
That impeller would be the best fit for the new motor. It would allow you to run at a lower RPM for a given flow rate in gpm. Your current impeller will work, but the listed impeller would be slightly better.
If I do have to get a new impeller will I also need a new diffuser?
If you went with a new impeller, you would need to go with this diffuser.
 

cowboycasey

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That impeller would be the best fit for the new motor. It would allow you to run at a lower RPM for a given flow rate in gpm. Your current impeller will work, but the listed impeller would be slightly better.

If you went with a new impeller, you would need to go with this diffuser.
@JamesW Thank you much... Now I have to figure out if 150 dollars of new impeller / diffuser is worth the squeeze? Do you think it would save that much? Currently I have to run 1300 rpm to use my SWG and 1100 the rest of the time. if it saves 150 a year then it is worth it but if it saves 10 dollars a year. hmmmmm.........
 

JamesW

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Mar 2, 2011
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It's probably not going to save much money. The power is roughly the same for the same flow rate. The smaller impeller has to spin faster than the larger impeller for the same flow rate. The primary difference is the faster rpm is noisier.
 
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cowboycasey

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Just as an FYI... It states on the pump 1.67 total HP with Service factor 1.0, I was going off info found on the internet, goes to show verify all information :) Thanks @setsailsoon

@JamesW I am going to get the new impeller, diffuser and seal and may be able to run a lower rpm :)
 
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