What would you do? Replacement pump...

js8390

0
Bronze Supporter
Apr 28, 2014
49
Pleasant Prairie, WI
My pumps life came to an end about a week ago, and I am in the market for a new one, maybe. Here's the thing. I have been researching pumps and flow ratings and everything I could think of to find a suitable replacement. I eventually decided on a 'Pentair 340038 SuperFlo High Performance Single Speed Pool Pump, 1 Horsepower, 115/230 Volt'. I figured this would be enough to satisfy my filtration needs, as well as my SWG needs to maintain a clean pool. I figured I'd wait to order this pump until spring of next year, so I don't waste any warranty time on having a pump sit in a box in the garage.

Now, in sharing the news of my pump with my boss at work, he mentioned we had a pool pump in a warehouse that was previously used, but that was going to be thrown out as it was no longer needed. This pump is a 'Pentair WhisperFlo Model# WFE-12'. So I took this home and now am wondering which way to go.

From what I understand my limiting factor (bottle neck) is going to be my piping which is only 1.5", and consists of 2 supply lines and 2 return lines. Key difference between the two pumps would be HP ratings (1HP vs 3HP [current is 1.5HP]) and required power (115V/230V vs 230V).

Now the question is simply which pump do I go with and why?

My concerns...
-Damage to piping with higher HP (found conflicting information on this).
-Run cost
-Turnover rate combined with SWG requirements (Hayward Aquarite w/ T-15 cell)

Any feedback is appreciated.
 
I advise not to go with the WFE-12, being a 3 hp full rated pump it has a total hp 0f 3.45, whereas the superflo has a total hp of 1.25. The larger pump would starve for water on 1-1/2 plumbing. The Superflo you are looking at, is the same as a 3/4 hp full rated pump, which would be smaller than what you have now but would work okay with your plumbing
 
You can't just compare the HP or THP on the motors. The Whisperflo is a different pump design and will move a lot more water than the Superflo ... even if the THP matched.

With 2 1.5" supply lines I do not think the pump would be starved for water. But, that Whisperflo is going to use a LOT more electricity when running than the smaller Superflo.

We do not really worry about turnover rate, your minimum run time is going to be set by how long it takes for your SWG to generate enough FC for your pool. So since, the run time is fixed by the SWG, the Whisperflo is just going to cost a lot more $ to run that long ... but how long would it take for that added electrical cost to become more $ than the Superflo would cost to buy (assuming the Whisperflo was free) ;)
 
Swap the impellor on the used pump. If you get a downsized impeller the pump wont move as much water. The motor won't use as much electricity but it will still be a huge energy hog compared to the 1hp superflo pump motor.

The superflo pump is a much better fit for your pool but its hard to not consider a free pump.

As for turnover either pump will move plenty of water for your needs. You really only need to run your pump long enough each day for your SWG to generate enough chlorine to maintain you FC levels. Any extra water flow beyond the minimum flow to keep the SWG on won't make a lick of difference how long that will take.

The only other reason you would need to run the pump longer than that would be to provide extra surface skimming or if you install a heater.
 
You can't really predict pumping cost because of the variation between environment, other equipment and owner desires. But let's just say you could do it with the 1HP for $30 a month, 6 months of the year - so $180.

No worries about pressure because residential pool pumps will not generate more pressure than the safe working load of the rest of the equipment and plumbing. You can change the impeller as mentioned, or throttle the 3 HP down to a reasonable flow rate, but even throttled down to 1/3 of what it can do, it's still going to use about 80% as much power as it would use unthrottled. Three times the power would be $540, times 80% = $432 per year (~$70 per month). These are super rough numbers, but fair to say the big pump would cost you around $200 to $250 more per year in power. If the new pump is around $400 to $500, you would break even after 2 years, and pumps last longer than 2 years, making the smaller pump likely to be more cost effective. A new right-sized pump will be quieter too :)

You could also consider a 2-speed pump, and get your power cost down more.
 
perhaps get a smaller impeller, and replace the motor with a 2 speed version. Might still be cheaper than the new single speed superflo and be cheaper to run due to the low speed.
 
Thank you all for your replies.

You pretty much said what I had anticipated, but as said, it's hard not to consider a free pump. It seems that the most simple route would be to go with the superflo as it would satisfy my pools needs and not have any added running costs that would come with the whisperflo with it's current motor. I suppose I will have an extra pump laying around for awhile.

I appreciate the help!
 
Honestly, I would seriously consider the suggestions in my last post ... price out a 2-speed motor as it would save you more $ on electricity than the single speed Superflo.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Superflo is $340, assuming I stay with the 1HP model.

I'm sort of hesitant to 'frankenstein' a pump as I'm not too familiar with changing out internals. I did come across one page in my research that showed a ton of steps to add a higher HP motor to a pump and everything that needed to be changed on the pump due to the more powerful motor, and it seemed like a hassle. I've got common sense and am mechanically inclined, but if I'd be invested a few hours between looking up parts I'd need, and then actually doing the work, I think I'd be better off just buying what I need versus building it. If I'm over estimating the work involved please let me know.
 
I think all you need is the motor, a new shaft seal, and a new impeller. That is all. Not sure what the other sites were saying you need to do ... or why anyone would go to a more powerful motor.

Would need to confirm that the Whisperflo does not have different diffusers for different HPs.

Steps (off the top of my head):
1. Split the pump (4-8 bolts)
2. Remove the old impeller (hold the motor shaft and unscrew it)
3. Remove the 4 motor bolts
4. Slide the motor out of the pump housing / shaft seal.
5. Slide the new motor into the pump housing and new shaft seal.
6. Attach the 4 motor bolts
7. Screw on the new impeller
8. Pump the pump back together (4-8 bolts)

May consider a "go-kit" and just replace all the o-ring seals while you have it open.

Here is a link:
How To Replace the Motor on Your Pool Pump - INYOPools.com
 
I don't see the point of spending all this time over a pump that you don't know the history of?? Just buy a new one they are not that much - $150-$300. Doesn't make sense to me to futz around on a $50k pool over a $300 pump.
 
There is zero upside to installing a 3 HP pump with downsized internals. Even with a lesser load the 3 HP will pull more amps than the lower HP pump.

AMPS ARE WHAT YOU PAY FOR ON YOUR ELECTRIC BILL! (volts x watts = amps)

This "free" pump may end up costing you several times the price of a right sized pump over its life. Do not outsmart yourself. Do it right the first time.
 
AMPS ARE WHAT YOU PAY FOR ON YOUR ELECTRIC BILL! (volts x watts = amps)

Watts are what you pay for $.xx/KWH. Watts are derived from amps x volts (volts x amps = watts). You are technically correct in that if the volts are constant the amps will have a linear value to watts. Higher amps = higher watts (assuming voltage is constant).
 
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.