Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 18 of 18

Thread: Autopilot and Salt water eating plaster and using acid

  1. Back To Top    #1

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    Autopilot and Salt water eating plaster and using acid

    I have had the following problem for 4 months. PH is dificult to maintain and the pool (15k) uses 3/4 of a gallon of acid a week (even in winter).

    Initially the plaster had a tremendous amount of scale from high PH as the use of PH caught the pool company off guard. The company emptied the pool and sanded the plaster (a very smooth specialist finish) back to its original smoothness and color.

    However, the pool continues to use acid and the plaster seems to be discoloring again and even becoming damaged. The pool company has been told that the problem is salt and the salt water cholorinator. Can anyone help as this is a big problem.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  2. Back To Top    #2

    Join Date
    Mar 2007
    Location
    Coastalish 'down easter'
    Posts
    4,160
    Sean, I don't have an answer at this point and I doubt anyone will without a full set of chem values for your water - If you would please post them someone might have an idea
    Luv& Luk
    -Ted

    Having done construction and service for 4 pool companies in 4 states starting in 1988, what I know about pools could fill a couple of books - what I don't know could fill a couple of libraries :-D

    POOL SCHOOL, TF Testkits, Jason's Pool Calculator, CYA vs. cl chart, (Just a few DARNED handy links!)

  3. Back To Top    #3
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879
    There are a couple of things that could be going wrong. We really need a full set of water test results to be able to tell which one applies here.

    SWG systems can cause rapid rises in PH when the chemistry isn't balanced properly. High PH in turn can cause calcium scale to form on the plaster, turning it white and rough. With a little more information we can tell you how to avoid these problems.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  4. Back To Top    #4
    Guest
    Your problems stem from improper water balance. Read the sticky on water balance for SWGs and you will get some info on what might have happened. Without knowing your water testing history I will venture to guess that your TA is too high and/or your CYA too low for a salt pool. Both these factors can contribute to ph stability problems and the formation of scale depos****. With proper water balance these problems can be greatly minimized!

  5. Back To Top    #5

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    CYA low - TA looks good

    Thanks to all for comments. I am using the Taylor 8 piece testing kit so while it does test for TA etc, it does not test CYA. I used a strip tester for that and it appears to be very low. PH is 7.4. TA is 80. FC is normally around 3 although I note today it is almost 1 (I did reduce the amount of time for the chlorinator this week). Given we have never used Chlorine - I guess the CYA is Zero.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  6. Back To Top    #6

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    Oily type scum in the skimmer weir

    Don't know if this is an additional data point, but there seems to be a very small amount of black greasy scum in the weirs.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  7. Back To Top    #7
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879
    You really need to get numbers for CYA and CH. Buying a high quality test kit is the best investment you can possibly make in your pool. I recommend TF Test Kits, see the link in my signature, and the Taylor K-2006 is also a great kit. It is also possible to get your water tested at most pool stores, though many of them take that opportunity to try and sell you things.

    With a SWG it is important that CYA be between 60 and 80. If your CYA is really zero that would be a serious problem. Don't just add some CYA without getting the CYA level tested. While it is easy to add CYA, it is very difficult to remove it if you add too much.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  8. Back To Top    #8

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59
    Thanks - amazing to me that the pool builder didn't do this.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  9. Back To Top    #9
    Guest
    Quote Originally Posted by ewsb
    Thanks - amazing to me that the pool builder didn't do this.
    From my experience I have found that most pool builders know very little about water chemistry or the proper way to set up a salt pool. I even has to alert the manufacturer of one very popular SWG about the number of pools I was seeing built by one particular builder in my area that were NOT set up properly (No CYA, among other problems). The manufacturer promptly arranged a training session for this builder and his staff. (Thanks 'You know who'!). I have not seen the problems since to the same degree but I have seen pools built by three other builders in my area with SWGs that also are not being set up properly. Part of the problem is that new owners do NOT read the manuals that come with their equipment and take responsibility for making sure their water is properly balanced and that their equipment is set up properly. I know we all assume the builder takes care of that but most don't. Many don't even do their own startups but subcontract this out (often to the low bidder! think about that!)

  10. Back To Top    #10

    Join Date
    Apr 2007
    Location
    Ft Lauderdale, Florida
    Posts
    1,455
    Sean Assam - Sean@teamhorner.com
    National Accounts and Commercial Products Manager
    AquaCal Heat Pumps www.aquacal.com
    AutoPilot Salt Chlorine Generators www.autopilot.com

  11. Back To Top    #11

    In the Industry

    Join Date
    Feb 2008
    Posts
    45
    You might also want to test the PH and TA of your tap water, before it hits the pool. If the tap water is far off on either of those, it could be throwing the pool off. Not much you can do about it, but it would be good to know.

  12. Back To Top    #12

    Join Date
    Oct 2007
    Location
    Valrico, FL
    Posts
    536
    I have a 7500 gallon pool that is also about four months old and I use at least 1 qt of acid per week to maintain pH.
    7,500 gal, IG pool, L shape 22' x 15', 1.5 hp pump, cartridge filter, AquaPlus SWG/Controller, Pebble-Tec liner.

  13. Back To Top    #13

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    Re: Autopilot and Salt water eating plaster and using acid

    A latest update; I am removing the saltwater system as I have now replaced 2 raypak natural gas heaters over the past 4 years (and raypak have advised me that it was the salt water that corroded the systems)
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  14. Back To Top    #14

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Autopilot and Salt water eating plaster and using acid

    So, has Raypak officially stated that their equipment cannot be used with a saltwater pool? I have never heard this before and I know there are thousands of heated pool that have successful SWG's.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  15. Back To Top    #15

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    Re: Autopilot and Salt water eating plaster and using acid

    No - as per my note they never said that - they said the salt water had caused the corrosion - (also noting the pool runs 12 months of the year). I have had an ongoing issue getting the salt water system to stabilize and I also now find that no 'sacrificial' anode had been installed which Raypak does advise if you are going to use a SWG. Even though we can do that, I just don't want to take the chance or the hassle as it has been too costly over the past 4 years.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  16. Back To Top    #16
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Autopilot and Salt water eating plaster and using acid

    Raypak is just trying to get out of honoring the warranty. That is a common problem with heater manufacturers and there is usually nothing you can do about it.

    If you kept your salt at the usual SWG levels, around 3,000 ppm, there is no chance at all that the salt contributed in any significant way to your heater problems, sacrificial anode or not. On the other hand, heaters are quite sensitive to low PH and can easily be destroyed by ongoing low PH.

    It would be worth your while to figure out what has actually been going wrong, otherwise the problems will simply continue, even though you have removed the SWG.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  17. Back To Top    #17

    Join Date
    May 2007
    Location
    Northern VA
    Posts
    59

    Re: Autopilot and Salt water eating plaster and using acid

    Jason - thanks as always and I am sure you are right. It just becomes impossible to disprove anything they say.
    Sean

    15 x 30 gunite pool with Riverflow Professional 12miles per hour flow (10HP silent ABB pump) to make the entire pool flow - Pentair Intellitouch i10 - Heat pump AquaComfort 110 - Raypak 399k Digital Gas Heater - Pool Pilot Digital SC-48 - Pentair FNS Plus 60 - Polaris 3900 Sport Cleaner on booster pump
    2 x Pentair Intelliflo pumps - one for filter (VF) and second for Venturi Pool Jets (VS) and Jandy 6 set deckjets - Pentair PG2000 Fiberoptic lighting - Automatic PoolCover (Brown) by Pool Cover Specialists

    Winter Pool Bubble by Ameri-Dome

  18. Back To Top    #18

    Join Date
    Apr 2007
    Location
    Ft Lauderdale, Florida
    Posts
    1,455

    Re: Autopilot and Salt water eating plaster and using acid

    The disproof is in the thousands of salt systems with heaters without problems. As a manufacturer, it's common for other manufacturers of equipment, pool contractors, service companies, etc, to blame salt systems due to a lack of knowledge, or it's just easier to put the blame on someone else. We hear it all the time.
    If you consider that pools running 12 month seasons, with Sodium Hypochlorite, and are not regularly partially drained/diluted, the salt level will get to 3000 ppm, the level of salt chlorine generators, within a few years. However, you won't hear the heater manufacturer void warranty and blame salt from sodium hypochlorite maintained pools. Why's that?

    Copper, or Cupric Nickel heat exchangers, are prone to damage from low pH conditions (as Jason mentioned), but also high chlorine levels, and improper water chemistry balance (per saturation index). The only direct results from a salt system are if you maintain salt levels in excess of 6,000 ppm, or if there is already an electrolysis issue. Salt will increase the conductivity of the water and accentuate the electrolytic effects.
    Sean Assam - Sean@teamhorner.com
    National Accounts and Commercial Products Manager
    AquaCal Heat Pumps www.aquacal.com
    AutoPilot Salt Chlorine Generators www.autopilot.com

Posting Permissions

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