Low salt reading and no salt generating

[ultimate_ed]

Entering into my 2nd summer with my pool and I'm about ready to punch my SWCG. It's a Pentair IC40 that came with the build last year. Through the winter, I would get low salt readings on the unit, even though testing with the Taylor drop kit would show good salt levels. So, I attributed it to the water being too cold for a proper reading and too cold for the SWCG to work anyway.

Things seemed to be going better in recent weeks as the water has warmed up, until last weekend. A daily check on the levels showed no FC in my pool. I doused it with a bottle of Clorox and have been trying to figure out what could be wrong now.

Once again, the unit is indicating low salt - 2400 ppm. However, my latest drop test indicates it is on the order of 3400ppm and that makes sense. I read about 3000 a few weeks ago after heavy rains did give me some losses due to the overflow drain.

Water temperature is currently 76 according to the unit, so I don't know what can be wrong with it now. As reported earlier, I did do one "cleaning" on the unit back in January, but found almost no build up in the cell as I've stayed on top of testing and adding acid to keep the pH under control. I've rarely had any scaling issues since I've had the pool.

I recall I had a similar issue a few months ago. I disconnected the unit and reconnected it to try to make it reset. Back then, it worked. However, so far, trying the same thing this time has not helped.

So, any suggestions on what can be giving me a low reading and no production now when the water temperature should be an issue any more? I figured I'd give it another go at cleaning it tonight to make sure that's not causing a problem.

 

[jblizzle]

What are the rest of your test results?

If there is something in the pool or the CYA is too low the SWG may not be able to keep up ... although that does not explain the salt level discrepancy.

Often low salt readings are a sign of a dirty or failing cell, but if it is only 1 year old, that would be pretty premature.

 

[ultimate_ed]

That's the thing, I've been keeping up with everything else pretty well. My CYA has been on the low side at around 40 (I've picked up some more to bring it back up), though I don't see that one causing me a low salt reading on the unit.

Didn't get a chance to open the unit today, I'll probably work on it this weekend and see how it responds to a cleaning.

 

[ultimate_ed]

Well, I think I'm going to have to call the builder for a warranty check on this one. Got a chance to do a cleaning on today. As before, nothing in the way of bubbling and no signs of scale buildup on the plates. Still reading low salt and after a couple of days, FC is dropping to 0.5 or zero. I've been hitting the pool with a bottle of clorox whenever I get a reading that has dropped down to zero again.

Other readings look good:
pH = 7.5
TA = 70
CC = 0
CYA = 40 (in the process of adding another 4 lbs to get that one back up to level)
CH = 270
Salt = 3400
Temperature = 78F

 

[jblizzle]

I would suggest raising the FC up to shock level and trying the OCLT to see if anything is in the water consuming the FC. You are letting the FC drop way too low.

Posted from my Droid with Tapatalk ... sorry if my response is short

 

[Pool Clown]

If the unit thinks the salt is low, it will not come on. You noted a Pentair pump, is your filter Pentair/Sta-rite as well? And did you get all this equipment at the same time (2012)? If so, you are under warranty, and should call tech support.

 

[ultimate_ed]

Yes, I purchased an all Pentair system, so I have the three year warranty. Now that I've done some due diligence and the unit still thinks the salt is low, I will be contacting my builder for a warranty call.

 

[Pool Clown]

You may want to cal Pentair directly. Calling Pentair and starting a warranty ticket also ensures your registration for warranty. If your builder is a warranty station, Pentair will probably notify them for the warranty service anyway, but typically it is up to you to register your equipment. If they aren't a station, you might want a company that is to insure that there wont be any problems with your warranty repair.

Calling Pentair over your pool builder is not something you must do, it's just advice.

 

[jaimejaime]

1 - take your water to a pool store for an accurate test. Strips and drops can go bad from heat, sun, or age, so be sure the problem isn'y your testing materials.

2 - my salt readings (and temperature) on my system are never accurate, so I don't even rely on it for my numbers.

3 - if the pool store confirms your readings, then it sounds like your cell isn't working properly. If your system took any kind of electrical hit over the winter, it *could* have thrown off the computer codes, and it may need to be rebooted and reconfigured.

You also want to watch how much outside chlorine you put in your pool. Cells don't like the shock treatment, and aren't designed to handle "artificial" chlorine, and can tweak from it. I think if you need to shock the pool, run your filter and infloor, but don't run the salt system.

 

[jblizzle]

Adding additional chlorine has no affect on the SWG. The reason we recommend turning it off is so that you get a better feel for the chlorine usage, not a worry about damage.

Also, it is a pretty far stretch to say that a pool store test is "accurate" ... trust your own testing.

Posted from my Droid with Tapatalk ... sorry if my response is short

 

[ultimate_ed]

Final update - as I suspected, it was the SWCG. Pentair sent out a guy yesterday and my wife thinks he was skeptical coming in. However, he told her that the old one read low salt and when he swapped in a new one, it read the correct salt level.

So, maybe it was the sensor part itself and not necessarily the actual generator, but either way I was getting no chlorine. Now we're back in business.

Thanks to all for the feedback and suggestions.