Become a TFP Supporter Welcome to our new server and new forum software. Pool School
Results 1 to 14 of 14

Thread: PVC threaded pipe sealant

  1. #1
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    PVC threaded pipe sealant

    I'm replacing some sections of PVC hose (1-1/2" tiger-flex) with PVC hard-pipe.

    For the the pipe-to-hose connections I decided to use screw-in barbed hose adapters (with clamps), requiring terminal female thread PVC fittings on the hard-pipe. I've followed what I thought to be correct practice - applying a couple of rounds of teflon tape to the male thread, screwing-in to hand-tight and then two more turns with a wrench - but found that hand-tight barely got the thread in half-way and two more turns required quite some force and still left a gap of about a 1/4". Tried with just one round of teflon tape and didn't fare much better.

    Seemed odd that fittings from the same manufacturer (Lasco) wouldn't completely screw together, so I checked their website and found they state that teflon tape should definitely NOT be used because it stresses the tapered threads and risks splitting the fittings....yikes !!! Nor should regular 'pipe dope' or teflon paste be used because they lubricate the joint and encourage over-tightening.

    http://www.lascofittings.com/supportcen ... lastic.asp

    The only thing they recommend is applying a non-hardening thread sealant compatible with PVC plastic.

    Are other people following this advice? - the contractor who installed my pool certainly didnt - all of the threaded connections were heavily teflon taped - might explain the several cracked fittings and copious amounts of silicone I found when disassembling the plumbing.

    Could anyone recommend a good, PVC compatible thread sealant?
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  2. #2
    Senior Member
    Join Date
    Mar 2011
    Posts
    3,230

    Re: PVC threaded pipe sealant

    http://www.permatex.com/products/automo ... ealant.htm

    Screw straight adapter, using Teflon pipe sealant tape or Permatex No. 2, securely into pump discharge. (Do not overtighten.)
    Screw elbow adapter, using Teflon pipe sealant tape or Permatex No. 2, securely into opening in control valve marked PUMP. (Do not overtighten.)
    http://www.hayward-pool.com/pdf/manuals/manual50.pdf
    On threaded valve connections use only Teflon® tape, 100% Teflon® tape, 100% Teflon® paste, or Permatex® #2 to seal the threads.
    http://www.pentairpool.com/pdfs/CleanandClearPlusOM.pdf

  3. #3
    Administrator JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    35,096

    Re: PVC threaded pipe sealant

    Teflon tape tends to be problematic for pipe connections of 1.5" or larger. For those larger threaded connections a teflon based non-hardening paste is most effective.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    TFP Admin. Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  4. #4
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    OK thanks.

    Just to clarify, it was the female 1-1/2" threaded PVC pipe adapters I was having particular issues with. No problem screwing male threads, whether that be pipe fittings, unions, nylon or poly hose adapters, fully into the filter and pump ports. In that case, teflon tape is definitely required for a tight fit, but, in view of Jason's comment, I might think about changing over to sealant if it works well with the female adapters, especially if it makes unscrewing threaded connections easier.
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  5. #5
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    Can't find Permatex locally. Do you think this would be a suitable alternative, or does it fall into the slippery/lubricating category of teflon-sealant that Lasco say should be avoided?

    http://www.rectorseal.com/RectorSeal-T-Plus-2.php

    Or maybe this one (Megaloc), which doesn't contain teflon:

    http://plumbing.hardwarestore.com/52-30 ... 56793.aspx

    Hmmm....on further reading looks to be oil-based and lubricant.
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  6. #6
    Administrator JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    35,096

    Re: PVC threaded pipe sealant

    The RectorSeal Tplus2 is the right kind of stuff, a non-setting teflon based paste.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    TFP Admin. Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  7. #7
    Senior Member X-PertPool's Avatar
    Join Date
    Jun 2009
    Location
    Exeter, PA
    Posts
    1,356

    Re: PVC threaded pipe sealant

    I use one or two wraps of teflon tape (don't make a mummy out of it). then apply permatex white teflon paste stuff. Hand tight then one more rotation with pliers. I've never cracked a fitting doing this. You are not to expect to get all the threads to disappear when tightening.

    This is the stuff I use
    http://www.grainger.com/Grainger/PERMAT ... _sku=2GXY8
    -Kevin
    X-Pert Pool Service
    x-pertpool.com
    X-Pert Pool on Facebook and @XPertPoolServic on Twitter
    22,000 gal / 16' x 32' / Vinyl / Hayward s244t /Pentair SuperFlo 1 hp

  8. #8
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    Thanks both of you.

    The RectorSeal Tplus2 I can get locally, so I'll give that a go first. I assume it could also be used with a little teflon tape if necessary, like for the filter and pump port connections.

    Quote Originally Posted by X-PertPool
    You are not to expect to get all the threads to disappear when tightening.
    Ah, OK, I thought you did.

    Thanks again.
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  9. #9
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    The RectorSeal Tplus2 wasn't available locally after all, but I found the Permaseal #2 (gasket) sealant in the Auto section of Canadian Tire.

    One question though. If used in combination with 1-2 wraps of teflon tape, is it really necessary to plaster the entire male thread with the Permaseal, as you would with less-expensive daub-on pipe thread dope, or is it sufficient to apply a bead of the stuff (since it comes in a tube) around the leading part of the thread and let the screw-action squeeze and spread it?
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  10. #10
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    Well I'm glad I tested the Permatex #2 on some old pipe fittings first. This stuff is wicked. Black like treacle (although in the picture on the packaging it looks white) and not so easy to get off white pipe once it's stained.....not to mention your hands. Yep, I'd say applying a bead of the stuff is the way to go. I'll maybe use it on the filter and pump ports connections and with the black (poly) barbed hose adapters. But for the tighter PVC-PVC screw fittings I can see myself getting into a mess.

    Short of finding the RectorSeal Tplus2 or Permaseal Pipe Thread Sealant with PTFE, (both of which are white), has anyone used Oatey's Great White Pipe Joint Compound in pool plumbing? It's stated to be suitable for PVC and is available in most hardware stores in my area. I'm just a bit concerned that it is stated to be lubricating.

    http://www.oatey.com/Channel/Shared/Pro ... _PTFE.html
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  11. #11
    Senior Member In the Industry

    Join Date
    Apr 2007
    Location
    Raleigh, NC
    Posts
    22,107

    Re: PVC threaded pipe sealant

    Short of finding the RectorSeal Tplus2 or Permaseal Pipe Thread Sealant with PTFE
    I just walked out to my shed a to look and I have a small can of both. I have used them interchangeably without issues.
    Dave S.
    Site Owner 42k vinyl and concrete pool, 1.5hp pump, 140gpm filter, No SWG
    TFTestkits owner
    TFTestkits , PoolMath , Pool School

  12. #12
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    Unfortunately, I can find neither of them locally. The only PVC compatible sealant the hardware and plumbing stores sell around here is the Oatey Great White stuff. The pool stores have nothing, only teflon tape. Wishing I'd taken the glued flex to PVC fitting route now. The wife is on to me to get the pool up and running this weekend
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

  13. #13
    Administrator JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    35,096

    Re: PVC threaded pipe sealant

    Oatey Great White is fine.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    TFP Admin. Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  14. #14
    Senior Member
    Join Date
    Nov 2011
    Posts
    127

    Re: PVC threaded pipe sealant

    Thanks, that's good to know, 'cos I've ending up using it on all the joints. A tech at the pool store had me going from pillar to post looking for Silicone GI which no-one had, and by that time I'd had enough.

    Anyhow, so far so good, at least on the suction line.

    On the return line I messed up. I was one screw fitting short and thought what the heck, I'll glue. In my eagerness to do it right (with the quarter turn) I got my markings mixed up and glued with the curve of the flexi pipe going the opposite direction. Typical !! I guess I could cut the hard pipe or flexi, fit a coupling and do it again, but that's more time lost ( and more ).

    I've read that flex can be straightened out using a hair-dryer or by placing in hot water. Thought it best to let the glued joint fully cure before trying, but what are my chances of curving the flexi in the opposite direction without ruining it?

    Sorry, I know this is off topic, but I'm a man under duress
    "Inherited" Cornelius 18'x54" Round AGP (Steel walls), Hayward Pro Series 21" Sand Filter, ClubPro (Jacuzzi) 1HP single speed pump, Lumi-O Festiva steps, Toile-Soleil mesh leaf net/winter cover. That's about it.

Posting Permissions

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