Lo SWG vs Hi Manual Salt Reading + Hi CH

[ontherocs]

First, I need to give a HUGE “Thank You” to all the TFP members!!! If it wasn’t for the imparted knowledge found on this forum, I tremble at how messed up my pool would be based on Leslie’s advice. ale:

Hunker down and get ready for the background. Figured providing it all will help in determining if the right steps have been taken and what else should occur.

A couple Mondays ago, I got a reminder from the pool guy (husband) that the SWG (Hayward AquaRite T15) was blinking. I headed out at lunch, noted the current level (3000), turned off the system, and checked the cell. Initial rinsing and scrubbing did not take care of the scale build up; however, a clean cell was reinstalled after several acid baths/rinses (1st time in 2.5 years) and the Diagnostic button pushed to reset the Inspect Cell indicator light.

After two days, the SWG unit still read 3000 so I assumed the salt level was low and added more salt (33 lbs) to begin bringing it up to what TFP considers the appropriate SWG salt level:

Range (2700-3400 AQR)+(200-400 TFP)=2900-3800
Optimum 3200 AQR + (200-400 TFP)=3400-3600

After a few more days, the SWG unit still read 3000. I pulled out my AquaChek strips and received a 5200++ reading!!!! WTH??? Luckily, I noticed that the bottled expired in 2011…Yikes!

I immediately grabbed a sample of water and headed to Leslie’s for a “professional” test and to buy some new salt test strips with pool guy in tow. After a good half hour of having to explain to the Leslie’s associate what “SWG” stood for (2 secs) and the following lecture on how high the phosphates were which could be causing the cell to provide an inaccurate reading, and how high the calcium was which was absolutely unheard of, and how high the salt level was which could burn the cell out and require a replacement, and how low the TA was which could destroy my plaster and attack all the metal in my pool, I was able to get out of the store with the number to Hayward for an immediate consultation, without any hard product sales (PhosFree+X+Y+Z) , and with a scared pool guy still in tow.

I kept my head knowing that the situation was not as dire as the Leslie’s associate made it out to be and performed my own quick tests:

[attachment=1:rlkhfgif]Test 1.jpg[/attachment:rlkhfgif]
Pool guy was asked to hold off on adding any acid for the next few days to raise the pH and the Desired (FC) Output was taken down a notch. The following day (yesterday) I purchased 8 lbs baking soda (50 cents a lb…what a DEAL!) and a new vial of test strips (exp 02/2014).

This morning I flipped the SWG to OFF and cut the power, then turned the power on and flipped it back on Auto. I also added 4 lbs of the baking soda and let the filter run throughout the day like normal.

I also checked the SWG unit diagnostics.

[attachment=0:rlkhfgif]Test 2 & 3.jpg[/attachment:rlkhfgif]
The SWG is definitely generating chlorine so I am not worried about it shutting off because the salt might be too high; but I don’t get why the default display will not update with an accurate reading. Also scratching my head as to why the Instant Salinity shows -0. From everything I have read, the unit can only be reset using the Instant Salinity amount so that will not be any help in trying to recalibrate the device. Is there any other way to calibrate it?

Although it appears the K-1766 has the same +/- range as the AquaChek strips, I’ll be ordering them tomorrow for a separate salt test. I will also be checking the CYA and testing the CH for both the pool and tap water.

Another question… when TFP provides a range to hit for the results, I try to get it in the center, but how bad is it if one amount is at the high end of the range and another at the low?

Again, many thanks!!!

 

[JasonLion]

Re: Low SWG Reading - High Manual Reading

Being anywhere inside the recommended range is just fine.

It would be helpful if you could do the SWG diagnostics when the cell is on. The numbers you reported were taken while the cell was off.

How old is the SWG cell? The cell typically lasts three to five years. If the cell is wearing out it will tend to report a lower salt level than actual. If you are getting calcium scaling it will also report a lower salt level than actual. It is difficult to tell if either of those might be an issue in your case.

 

[ontherocs]

Ahhhhhh... After I came in and started last night's post, I had a feeling that the unit should be set to auto while I was taking the readings; but, the HUGE black widow that was keeping me company while I gathered the first set by flashlight dissuaded me from returning for new readings.

[attachment=0:2uzn28hm]Test 4.jpg[/attachment:2uzn28hm]
Looks like the TA and pH have stabilized. Still confident the SWG is generating chlorine and scratching my head as to the low Instant Salinity reading. And now also worried about the low CYA and crazy high CH levels.

Should I still be concerned that the unit is reading incorrectly? Is there a way to recalibrate? Or am I now resigned to manually calculating salt?

The CYA has been consistently 70-80 when I have checked in the past. It has been a few months so I am not sure how long it’s been at 30-40. I read somewhere in the forum that low CYA could cause cell failure? How low is too low?

I also add ProTeam Supreme Plus as a borate. Both CYA and borates are described as stabilizers. Is there a difference?

The weather has been in the high 80s to low 90s for a solid week, acid has not been added since Monday, and everything seems to be climbing at a slow steady pace, as I would expect.

If I do need to bump up my CYA and cannot use the Supreme Plus, what liquid stabilizer is best to use?

As for the CH. I had always not been overly concerned because we live in an extremely high hard water area. Leslie’s mentioned that a new water source is being used and that prompted my testing of the tap water. Totally surprised that it’s as low as 400. I actually tested it twice. The pH and TA have stayed in range more than not. I read on the forum that as long as those stay in check, and there are no scaling or cloudiness issues, not to worry? Are there any other possible problems that can occur that would warrant draining/refilling the pool?

Another range question… Is it best to allow the pH to raise past 7.8 and bring it back down to 7.6 or to bring it down lower than 7.4 and allow it to come back up to 7.6?

Thanks in advance for any help!!!

 

[ontherocs]

Hoping I can still get some of the questions answered above but also wanted to give a quick update.

Added 1 gallon of Liquid Conditioner Monday afternoon. Also received the K-1766 Taylor Salt Test drops yesterday.

Yesterday's #s
FC: 4
Salt: 4200
CYA: 60
TA: 70
pH: 7.7

Forgot to respond to JasonLion's comment re: calcium scaling causing the reading issues. Scale build up was removed with an acid bath prior to beginning this whole research process.

Even though not at optimum levels, thinking it's still okay till the end of the season. Is that way off base? With the CYA at 60, should I still work at getting it up to 70 even though FC is pretty stable? Is it better to bring up the CYA to 70-80 and reduce the percentage on the SWG unit? We have the dial set to 80 but it looks like the unit is actually producing at 87%.

Took some picts while doing the salt reading:
[attachment=1:3m0jn8b8]Salt Test1.jpg[/attachment:3m0jn8b8]

Is that the "red brick" color I'm supposed to be looking for? Adding more drops didn't really make it turn brown, just muddy.

Also, there seemed to be a lot of deposits:
[attachment=0:3m0jn8b8]Salt Test2.jpg[/attachment:3m0jn8b8]

What's that all about?

The pool guy was already considering draining some of the water and replacing because he had heard that was a good practice. Is that something that should be considered as routine maintenance? If so, how often? Are there pros/cons?

Thanks again! And sorry for the lengthy posts. Again just hoping to give as much info so you all can provide your suggestions.

 

[ontherocs]

Haven't added anything new except for the needed acid or replaced any water. Just keeping an eye on the numbers:

[attachment=0:yws8qcuk]Test 5.jpg[/attachment:yws8qcuk]
The salt has come down slightly on both the manual tests and the SWG. Reading through the manual, it appears that the SWG will shut down if the salt level is too low, but it does not mention how low.

I will keep on doing the manual tests and monitor the unit to see at what level it finally decides to shut off.

 

[ontherocs]

As for the CH. I had always not been overly concerned because we live in an extremely high hard water area. Leslie’s mentioned that a new water source is being used and that prompted my testing of the tap water. Totally surprised that it’s as low as 400. I actually tested it twice. The pH and TA have stayed in range more than not. I read on the forum that as long as those stay in check, and there are no scaling or cloudiness issues, not to worry? Are there any other possible problems that can occur that would warrant draining/refilling the pool?

Found where the forum discusses the CH level:

Adjust Calcium Hardness to 300 ppm for plaster and 250 ppm for fiberglass. Vinyl pools are OK if the CH is at 50 ppm or higher. In any case it should not be much above 400 ppm or you are going to have to keep close watch on your pH to prevent scale buildup. Sometimes your fill water will have high calcium levels so your numbers are higher than recommended. Not really that big an issue if you maintain your pH as recommended above. pH rise is the ONE FACTOR that will predict scaling condition. High pH leads to scaling, period! Keep pH below 8.0!

Update on SWG reading... I think it finally got down to 2400 and was blinking consistently even tho the cell was clean.

No matter... my husband (aka. pool guy) could not keep from draining the pool this weekend. It's in the process of being refilled as we speak. Chem restart posts to come.