FNS Plus Poor Backwashing

[cr500]

Hi All,

Newbie to the forum.

I take care of my parents inground pool (16x32 cement wall vinyl liner). Several years ago I had to replace the 25 year old Lomart DE filter (disc elements with a handle so they could be spun during backwash). I ended up getting the Purex Triton FNS Plus 36. This filter has never backwashed cleanly. I let it backwash for a long time, turn it off and on, go back and forth between backwash / filter, ... but always seems to have pressure creep during the season. I disassemble it at the end of every season and am always amazed at the amount of DE that seems to remain in the filter.

Anyone have a good routine for this filter?

I think that old Lomart was a better filter, I can't believe they went out of business. One of these days I'm going to try and build a Lomart copy!

Thanks!

 

[no-mas]

Welcome to the forum.

I have the same filter - well, the pentair version. Every other time I backwash, I remove the lid, open the drain at the bottom of the filter tank, and hose down the grids. It's not quite as good as a full breakdown and clean, but it gets much more DE out that would otherwise have remained behind after backwashing.

 

[cr500]

Bummer. Thats too much work for my dad. I usually only open / close the pool since I'm a few states away.

I did notice on the label they recommend disassembly biannually. Geesh, that old filter could go several seasons before opening it up.

Thanks

 

[Heckpools]

instead of going from backwash to filter, try backwashing, then to rinse and then back to backwash..( do this a few times) also, when you add the new de powder, add 1 pound LESS then it says too.. when you backwash not ALL of the de will come out, so if you continue to add the amount it says too, by the end of the season u'll have a caked up mess!

 

[Aurelius]

hello all -
I think I have the same model for my pool.
The system is about 9 years old.
Over time, it has become difficult or impossible to read the labels on the controls.
There are 6 settings that go around clockwise. The handle goes around and locks into notches at:
12 o'clock
2 o'clock
4 o'clock
6 o'clock
8 o'clock
10 o'clock
I am sorry for the long post, I'm having some trouble explaining this.
Basically what I need to know what these settings are for the filter system.
Here are the settings that I do know:
12 o'clock is "BACKWASH"
6 o'clock is "FILTER"
4 o'clock is "RINSE"

Can someone help me fill in the gaps?

 

[cr500]

I'll give it a shot next season! What's the flow pattern when in rinse?

Thanks

instead of going from backwash to filter, try backwashing, then to rinse and then back to backwash..( do this a few times) also, when you add the new de powder, add 1 pound LESS then it says too.. when you backwash not ALL of the de will come out, so if you continue to add the amount it says too, by the end of the season u'll have a caked up mess!

 

[polyvue]

hello all -
I think I have the same model for my pool.
The system is about 9 years old.
Over time, it has become difficult or impossible to read the labels on the controls.
There are 6 settings that go around clockwise. The handle goes around and locks into notches at:
12 o'clock
2 o'clock
4 o'clock
6 o'clock
8 o'clock
10 o'clock
I am sorry for the long post, I'm having some trouble explaining this.
Basically what I need to know what these settings are for the filter system.
Here are the settings that I do know:
12 o'clock is "BACKWASH"
6 o'clock is "FILTER"
4 o'clock is "RINSE"

Can someone help me fill in the gaps?

Welcome to the forum, Aurelius... :-D

Though I can't answer your question, perhaps others here have experience with the Purex Triton filter and can.

 

[Durk]

Aurelius: Missing notches would be Closed, Recirculate, and Waste. Should be easy to figure out. Waste will expel water direct to waste. Recirc will send it straight to the returns. Closed will not let it go anywhere. Pump will sound weird and pressure will ramp up fast. So just give the pump a bump until you know the one you are trying is NOT the Closed position. You don't want to leave the pump spinning in Closed position. I'd bump all three unknowns until I saw some water come out the waste pipe/hose. That's Waste. Then have someone put a hand over a return and bump the other two. The one that goes out the return is Recirc. The last one is therefore Closed. Of course, if someone is familiar with your unit and knows, that's even easier.

Heckpools: Rinse is the same as filter except output goes to waste instead of back to the pool. It helps keep crud/DE out of the pool, but I don't see how it would clean any better than going B'wash/Filter. B'Wash/Rinse is the preferred approach for the reason I cited. One thing I do is watch the sight glass in the waste line (or on the MPV) and see how much new crud/DE is being exhausted with each mode change. I stop doing it when I no longer get a new shot of cloudiness when I switch to B'Wash.

 

[Aurelius]

Thanks Durk!
That will help me.

 

[PoolGuyNJ]

The purpose of Rinse on both DE and Sand filters is to remove any debris that in the return side of the filter's plumbing during backwash.

I have found adding a 30 filter cycle after Rinse and then repeating the backwash-rinse cycle to be somewhat more effective.

Scott
PoolGuyNJ