Hayward SwimPure not generating enough Chlorine

[pdpantages]

Hello Forum, I have a prob with my SWG and wondered if anyone has had/seen this issue.

Just fyi, my water analysis report today ( from Leslies ):
FAC 0
TAC 0
Salt 2800
CH 200
CYA 30
TA 110
pH 7.8
Copper 0
Iron 0
Phosphates 150

Also:

Pump run time 10 Hr/Day
Pool size 14000 gal.
Location DFW Texas
No visible algae in pool

Problem: I had a Swimpure Plus installed around March 2012. It worked fine for 2 years when the main circuit board failed. It was repaired under warranty, and did work after this but I noticed I had to turn the generation % up quite a bit, compared to the original. That is, where I used to run it arount 50-60% in the summer, I now required 80-90%. This didn't bother me (maybe it should have) as I thought this was just a calibration issue, and as long as it worked I didn't care what the % setting was.

But this problem has dogged me over the last year; even at higher %, it can't seem to keep up the chlorine level. I remember in the winter having to turn it way down to keep the CL at 2-3 ppm. I have had the cell tested by Leslies, which tests OK on a few occasions. My SWG reports 27V, 5A across the cell- it should be generating Chlorine.

I contacted Hayward support again today and I was told that the readings (below) are normal and it all must be due to my phosphate level, which is high at 150 ppb. I don't find this too believable, but I am working on bringing my CYA and Phostphates in line.

My SWG Diags are:
60F water temp
27.6 cell voltage
5.27 cell current
100P run percentage
-3000 instantaneous salt level
AL0 Model
R.159 SW version
T-15 Cell type

So, has anyone experienced this type of problem? In particular, with a new circuit board installed, a change in % setting required.

My software version on the board is 1.59 (I don't know what the original was). Anytime I mention the change in behavior (different % required as soon as new board installed) both Leslies and Hayward just gloss over it; explaining that the difference must be due to cold water temp, warm water temp, water chemistry etc. etc...

I am keen to get this resolved before it warms up too much here in Tx..

 

[JamesW]

At 60 f, output is reduced to 20% of output setting.

Your numbers look ok. Try an overnight chlorine loss test.

 

[pooldv]

I leave my SWG off until the water gets to 60, I use bleach until then.

 

[pdpantages]

Thank you JW for the info.

I didn't know that output was based on temp- I thought that, for example, a setting of 50% would mean the generator would be on for 1/2 of the pump run time. I.e., the 50% is a "duty cycle".... I am basing this on the fact that I sometimes see a current of 0A when I check the diagnostics. Do you mean to say that the duty cycle is *reduced* by the controller (based on temperature reading), or just that cell efficiency is degraded at lower temperatures?

I will try the overnight test, but I have to wait for my FAS-DPD test kit to arrive from Amazon.

 

[JamesW]

With Firmware Revision 1.55 (5/8/2009) the cycle time (reverses polarity) changed from 120 minutes (2 hrs) to 180 minutes (3 hrs). When you set the ‘Desired Output %’ dial on the main panel this sets the level of salt cell operation as a percent of the operating time of each cycle. 50% is the factory default. Below are simple examples for 2 and 3 hr cycle times.
• 2 hr cycle If the output is set at 50% and the total time for operation is 8 hrs, the salt cell will operate (and produce chlorine) for 50% (1 hr) of each 2hr cycle for a total of 4 hrs.
• 3 hr cycle If the output is set at 50% and the total time for operation is 9 hrs, the salt cell will operate (and produce chlorine) for 50% (1.5 hrs) of each 3 hrs cycle for a total of 4.5 hrs

At 60 f the output is scaled back to 20 % of the percentage setting. Your 0 fc indicates that you're allowing the chlorine level to go below the minimum recommended amount. When that happens, you get a buildup of chlorine demand.

Your CYA is too low for a salt pool. Your high TA is probably creating excessive ph rise.

You should get a good test kit to test your own water.

 

[Isaac-1]

I think there is some confusion in this thread, the controller does not turn down the run time when the water is cold, instead chlorine production is greatly lowered for any given run time when water temperature is low and many brands of SWG's completely shut down when water temperature gets into the 50's.

 

[JamesW]

The r 1.59 version has a cycle time of 180 minutes. Above 60 f, the percentage setting determines the amount of time the unit runs per cycle.

For example, a setting of 40 % will produce chlorine for 72 minutes and then be off for 108 minutes.

If the water gets to 60 f, the production at 40 % would be 180 x 0.4 x 0.2 = 14 minutes on and 166 minutes off per cycle.

 

[pdpantages]

Thank you all for your comments. I didn't know about the scale-back at 60F and lower; otherwise the explanation of the duty cycle fits with what I was thinking.

I do have a DPT test kit; it only tests CL, PH, TA though, so I take my water to Leslies occasionally to see if the salt level matches what the Hayward is telling me, and to get measurements for CYA etc.

My test kit shows me 70-80 for TA; this is consistently lower than what Leslies comes up with. This kind of bothers me a bit as I am not certain which is correct. Salt also is lower (2800) than what my SWG comes up with (3000). When I first got my SWG it usually reported within 100ppm what I got from Leslies.

I will work on getting the CYA up to 75 or so, and will put some bleach in to bump the chlorine up in the meantime.

 

[pooldv]

Phosphates are not the issue. TFP does not even recommend testing for them, I have never tested phosphates in my pool.

Here is the recommended chemistry for a saltwater pool, Pool School - Water Balance for SWGs

Pool store testing is not reliable, not to mention they always want to sell you something after that free water test. Get a recommended test kit and do your own testing, Pool School - Test Kits Compared. I use the TF100 from TFTestkits.net.

Start here for managing your pool, Pool School - ABCs of Pool Water Chemistry

 

[pdpantages]

Hello All, some progress. I have my new test kits from Amazon (K2006 is on sale) and can test CH and CYA (also got a kit for salt) as of today.

Last week, I looked at the pool math calculator, and added some bleach, CaCl, Salt and Stabilizer ( I added 1/2 the recommended amounts and let it stew for 7 days ).

The good/bad news is, my SWG must be working. The bad news is, I was a bit sick last week and did not test my chlorine daily... I had left my SWG at 99%; at the time this was able to maintain 0-.5 FAC-- but the water temp is now 64F and my FAC is now off the charts at 23ppm . So I guess it is working well. I shut the SWG off and will let the FAC drop down to normal levels.

My question is: despite adding 2lb of stabilizer, my CYA is now <30 according to the test kit. Does the high FAC levels impact/invalidate this test? I plan to retest once FAC is < 5 but if the test is accurate I may as well put the remaining 2lb of stabilizer in today...

Oh, and just FYI, last time at Leslies, he gave me the usual 110 for TA; I mentioned that I usually get 80 for this; he retested, and got 80 as well the second time...


FAC 23
TAC 28
Salt 3600 (Swg reads 3300)
CH 230
CYA <30
TA 90
pH 8.0
Temp 64F


PdP

 

[JamesW]

2 lbs cya in 14,000 gallons is only 17 ppm.

Fc does not affect the cya test. The test can be difficult to do and get consistent results. Don't get too concerned about the exact level. Just test and adjust as needed to get in range.

 

[pdpantages]

2 lbs cya in 14,000 gallons is only 17 ppm.

Fc does not affect the cya test. The test can be difficult to do and get consistent results. Don't get too concerned about the exact level. Just test and adjust as needed to get in range.

OK James, thank you. I understand about the CYA; I just thought it would be better to put in 1/2 the recommended amount... I expected to see CYA 40-50 (used to be 30) as a result.

I am going to adjust and test (everything) as you recommend.

Thank you for all the help.