What variable speed pump should I buy?

[dobe12]

Hi:

I have a 25,000 gallon pool with a small (3 person) spa. I currently have an old 1.5 HP single speed pump. To save on my electric bill I'm considering buying ($699) a Pentair 1.5 HP VS 342001.

One of my friends seems to think a 2.0 with a Full head would be better, but those pumps seem to be at least twice as expensive. The Pentair is a medium head.

Someone told me I might need to run the Pentair at full speed to match my current pump. If true that would negate the purpose of my switch to VS.

What would you suggest?

Thanks!

 

[ajw22]

Welcome to TFP.

If you want to save on your electric bill then a 3HP VS pump running at 1 HP will use less electricity then a 1.5 HP pump running at 1 HP. I am using 1 HP as an example but whatever RPM and HP your pool needs.

The pool head is not what dictates VS pump requirements. We need to know the details of your pool and equipment to say what pump is best. Please create your signature with details of your pool and equipment.

 

[dobe12]

Thanks for the response. I don't know much at all about pools. I added a signature. I don't know if you need more information. I'm interested in saving on my electric bill with a VS but I'm also interested in preventing black Algae in the spring. It gets really bad for about 4-6 weeks starting in late April. My pool guy puts all kinds of chemicals in it but it still takes about 6 weeks to clear up. That's why I just had the Hayward Glass Filter installed. Would the right VS pump also help reduce the algae in the Spring?
Attached Photo of pool.
Thank You!

 

[wireform]

You have 2 separate issues here. For one you need a motor, secondly the black algae isn't motor related but "pool stored" it surely is. Stop wasting $$$ with the pool guy loading up the water with chemicals that obviously don't work. Read pool school here and do your own testing with a TF-100 test kit. You can turn that pool around like many here have.

 

[MiguelACA]

If you're getting algae, then your chemistry is off and your pool guy isn't doing it right. Get yourself a test kit and post your chemical levels. I am relatively new here, but have learned A LOT! There are very knowledgeable people here!

 

[dobe12]

Thanks. Good to know about the algae. I thought running the new VS pump 24/7 and back washing the glass filter weekly, during spring algae time, would help with the algae. The old paper filter wasn't cleaned enough during the algae period because it was such a hassle.

So, the the other question is what VS pump would be best for my pool? I want to save on electrical bill even if it won't help with the algae but I don't want to pay too much for the pump. The Pentair 1.5 HP VS 342001 is $699. Plus $200 to install.
Thank you

 

[gx22]

I have this 342001 pump for 3 years. It works great. I like its 3-inteval internal timer and economical. If you use automation, you have to wire it to be controlled by automation relays. Intelliflow pumps have an automation jack and that method is easier.

 

[kadavis]

How many spa jets are in the spa, it may be that the 342001 can't produce enough flow at the higher head that spa jets produce. Otherwise, for just filtration it is a decent pump.

 

[dobe12]

Thanks for your responses.

The Spa has 3 jets. Here's more info about the pool.

AGP 25,000 gallons 31' x 20' + Spa 8' x 5.5' (3 jets)

Polaris 280; Booster Sweep Pump .75 HP

Hayward (A.0. Smith) Single Speed Pump 1.5 HP RPM 3450 SF: 1.33 FR: 56J
PH: 1 Type: UAK

Hayward W3S270T Pro-Series Glass Filter, 27-Inch

From pump to closest end of pool is 22'

Pump is same elevation as pool

Plumbing size is 2"

Nothing wrong with the current pump except it's very old. I tried to find the age but couldn't find info on the internet. The internet did say similar pumps rated 1.5 HP are Full rated motors so the actual total HP is 2.25. Not sure if that applies to my pump.

Also, not only do I want to save on my electric bill, I was hoping a variable pump, properly used, along with my new glass filter would help avoid the black algae I get every Spring. It lasts about 6 weeks or more. My pool guy says he does what he can, with chemicals, but says I have too many flowering trees and vines in my yard.

Apparently the glass filter backwashed weekly in the Spring and the variable pump running 24/7 at the correct speeds won't help with the algae?

Does everyone agree?

I look forward to your input!

Thanks. Doug

 

[ajw22]

Filtering does not fix algae problems. You can filter day and night and it will not improve an algae problem. The proper level of chlorine over a sustained period is needed to rid a pool of algae. We call it the SLAM Process.

I suggest you read ABCs of Pool Water Chemistry and we have a lot about proper water chemistry in Pool School - Trouble Free Pool

The serial number on you pump will tell you the age - Hayward Serial Numbers and Date Codes - Further Reading