Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 10 of 10

Thread: Pentair FNS plus has a small leak. Any ideas?

  1. Back To Top    #1

    Pentair FNS plus has a small leak. Any ideas?

    Hi All,
    I have a Pentair FNS plus 48 DE filter. It has a small leak around the separation between the upper and lower tank. I replaced the large o-ring last year. Any ideas how to stop it. IIRC I had the same leak last year but it wasn't nearly as bad. It was very slow. Even now it just seeps out but it annoying. I don't want to buy another o-ring if it could be another problem. Also I installed the o-ring dry. I didn't use any teflon lube. I'm not sure if that's correct or not.
    Thanks for the help,
    Joe
    15,500 gal, inground gunite pool with 7 ft spa, 2 speed pump 2hp/.33hp, 3/4 hp booster pump, Intermatic P1353 timer, AutoPilot SC-48, Sand filter with ZeoBest, Heater, that I never use . . .

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Pentair FNS plus has a small leak. Any ideas?

    If it is like my Hayward, you are supposed to lube it up good when you install it. That is the likely cause of your leak. And should be a pretty cheap fix
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,347

    Re: Pentair FNS plus has a small leak. Any ideas?

    I agree you should lube it well. That large an o-ring needs to 'settle' into place and without lube it can't do that.
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/¼hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  4. Back To Top    #4
    maxepr1's Avatar
    Join Date
    Mar 2011
    Location
    DFW
    Posts
    716

    Re: Pentair FNS plus has a small leak. Any ideas?

    Lube the O-ring and adjust the band clamp and re-torque.
    40'x19' IG Diamond Brite 29K 4' Waterfall/Dive Rock FNS60 DE Inteliflo VS 2hp Whisperflo pumps Aqualogic(P4) SWG TF100 Tester


    Pool School, Pool Calculator,TFTestKits,

  5. Back To Top    #5
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Pentair FNS plus has a small leak. Any ideas?

    I also want to add that when I am tightening the band clamp I get it snug and then tap on it all the way around with a rubber mallet to seat the band some more. Then tighten and tap, tighten and tap, etc until the bolt/nut stays torqued to the correct spec after tapping.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  6. Back To Top    #6

    Re: Pentair FNS plus has a small leak. Any ideas?

    Thanks for the tips. Is there a torque value for the nut. I didn't see one listed in the manual.
    15,500 gal, inground gunite pool with 7 ft spa, 2 speed pump 2hp/.33hp, 3/4 hp booster pump, Intermatic P1353 timer, AutoPilot SC-48, Sand filter with ZeoBest, Heater, that I never use . . .

  7. Back To Top    #7
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Pentair FNS plus has a small leak. Any ideas?

    On my Hayward you tighten until a spring is compressed and touching ... not sure about the Pentairs.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  8. Back To Top    #8
    maxepr1's Avatar
    Join Date
    Mar 2011
    Location
    DFW
    Posts
    716

    Re: Pentair FNS plus has a small leak. Any ideas?

    It says to compress the spring until the coils touch each other.
    40'x19' IG Diamond Brite 29K 4' Waterfall/Dive Rock FNS60 DE Inteliflo VS 2hp Whisperflo pumps Aqualogic(P4) SWG TF100 Tester


    Pool School, Pool Calculator,TFTestKits,

  9. Back To Top    #9

    Re: Pentair FNS plus has a small leak. Any ideas?

    meh, I did all of the above and still have some seepage. Any other ideas?
    15,500 gal, inground gunite pool with 7 ft spa, 2 speed pump 2hp/.33hp, 3/4 hp booster pump, Intermatic P1353 timer, AutoPilot SC-48, Sand filter with ZeoBest, Heater, that I never use . . .

  10. Back To Top    #10

    Re: Pentair FNS plus has a small leak. Any ideas?

    Quote Originally Posted by cruzmisl
    meh, I did all of the above and still have some seepage. Any other ideas?
    How much lube did you use?

    This year when putting everything together, I cleaned all of the connecting surfaces of both tanks, and the o-ring. I put it back together forgetting to lube it up and it was leaking.

    I took it apart, lubed up the o-ring real well and put it back together. Still leaking!

    So I took it apart again and lubed the ring again, plus the lips on the top and lower tank. Put it back together, no more leaks.

    It can take a lot of lube, especially if you are starting with None. My o-ring seems to absorb a lot of this stuff.

    Also, I use something called o-ring lube that my pool supply store stocks, its nasty green stuff, but made specially for this application.
    16,000 gal in-ground
    Pump: Hayward C48K2N143 1HP 230V
    Filter: DE Triton Nautilus FNS-36

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •