Pentair - FNS, SMBW or Quad Filter

[kevinm2]

It's time to change my pump and DE filter. I am planing to purchase a 2 speed, 1 1/2HP, Full rated, WhisperFlo (Model WFDS-6). I am confused over choosing which filter to purchase. Which is a more preferred and better filter for my environment. There are no trees or gardening around the swimming pool. But the pump and the filter are exposed to the harsh SoCal sun. And I also have a solar heating system with 2" PVC pipes in and out.

following are my choices:
1) Quad D.E. 60 - W/ an added Back wash valve
2) FNSP60 - W/ an added Back wash valve
3) SMBW 4060

I would appreciate help from this board. Thks

 

[Bama Rambler]

Welcome to TFP.

If you're happy with the filter you have now any of the filters you listed will work. I would, however, recommend you go with Quad DE 80 or 100. The quad 80 is only a little more than the SMBW 4060 and the 100 is only a little more than that. The larger filters will give you more time between backwashing and therefore you'll possibly use less DE due to recharging.

 

[kevinm2]

Nautilus 48 sq ft, my existing filter, did a nice job cleaning the pool. But since it's made out of aluminum, it has rusted and has started to leak.

So you would recommend A Quad filter over FNS and SNMB!

Sorry but I have more questions
1) How long is approximate life of a Filter Cartridge and A Filter Grid? Which one is more desirable?
2) Is a backwash valve really needed with Quad Filter?
3) Which filter casing (the shell) is more Durable under the sun?
4) Are cartridges more expensive to maintain than grids, when it's time to change them relative to usage.

 

[Rangeball]

I have had the FNSP36 on my 21,200gal pool for 10+ years. It sits in full sun and I leave it out in the winter. I just now have to replace the spider gasket as I'm getting a bit of a leak to waste when filtering, but other than that it's still going strong and has performed flawlessly. I have the added MP valve, and since taking hold of my own pool and going BBB, I start up, swim all season, and backwash once at the end of the year to clean the filter before breaking it down for a full cleaning.

Can't speak to the others, but if this one ever goes down, I'd be very happy with another just like it.

 

[JasonLion]

There are no significant differences in lifetime between grids and cartridges in a DE filter. Some people feel that the cartridges are a little easier to clean, but others say they are about the same.

Having a backwash valve with a DE filter is not required, but most people prefer to have it. Getting a full multi-position valve can be very nice because of some of the other features it offers, like filter bypass, but isn't essential.

All of the filter casings sold these days will last longer. even with sun exposure, than most of the rest of your pool.

I recommend getting the largest filter you can afford. Design details (ie grid or cartridge) are relatively unimportant.

 

[kevinm2]

Jason you explained it all.

More questions,

Would the electrical consumption be a lot more significant, if I purchase an Intlitflo VF over a WhisperFlo (Model WFDS-6), running it at a low speed and in my environment?

Also I have 1-1/2 inch PVC coming from and back to the pool. All these pumps have 2" ports. Would that be a problem using any of the above pumps?

Thank you.

 

[JasonLion]

The IntelliFlo will use less electricity. You will probably save something like 35% by running the two speed pump on low (compared to a single speed pump), and save 50% or a bit more by using the IntelliFlo. So the IntelliFlo saves electricity, but depending on your electrical rates it might not save enough to pay for the price difference.

 

[kevinm2]

I have 1-1/2 inch PVC coming from and back to the pool.

These pumps have 2" ports. Would that be a problem using any of the above pumps?

 

[JasonLion]

Using 1.5" pipe has some disadvantages, but it will still work just fine. Ideally you want to have at least foot or two of 2" pipe before and after the pump and then step down to the smaller pipe size further away, but even that is not critical.

 

[kevinm2]

Just going crazy between techs and Pump Manufacturer. Everyone says something different. So I decided to show this board some pictures and some more information for some help.

*The pump has 2" suction and an 1.5" pressure outlet
* Pool size 28000 Gallons

- From the skimmer and pool bottom suction a 1.5" PVC with a 2" elbow to the existing 1.5HP single speed Pump
- From the pump a 1.5" PVC to Existing filter
- From the filter a 2" PVC to the solar system through Goldline valve & thermostat controller
- On the way back to the pool, a 2" PVC through the copper valve to two 1.5" PVCs. One is for the return of filtered water to the pool and the other is for the Polaris pool cleaner. I used to put this valve in the middle. so both the Polaris cleaner and the returned flowed together. Polaris didn't do a good job!

I spoke to Pentair and now they saying that I have to measure and gauge the Vac. and Pressure of the pump. So they could tell me whether I should purchase a 1HP or and 1.5HP whisper-flow. The measurements are as follow:

Without Solar
Vaccum measured value=13*1.13=14.69
Pressure measured Value =15*2.31=34.65
Total Head of 49.34

With Solar engaged
Vaccum measured value=11*1.13=12.43
Pressure measured Value =17*2.31=39.27
Total Head of 51.70
Note: These measurements were taken, while the filter was leaking.

What type of horse power and how much of a filtration (sq.ft.) would I need.