I have an in-ground pool I got with my new house, in which I inherited an Aqualogic SWCG. The salt-cell itself had been taken out (because it froze and shattered over the winter), but I just got it replaced yesterday, with a GLX-CELL-5 model.
Since the replacement, the system has been giving me "Low Salt" errors, with a salt level that very much disagrees with what I measure using my K-1766 test kit. To make sure I wasn't messing up the test I sent a sample to the company that installed the thing for them to test the salt, and sure enough--the salt level they read was 1710ppm, my reading was 1800, and the display board for the AquaLogic says 700ppm.
I asked the company to fix it, and they dumped a bag of salt in the pool (without asking first) and did nothing for the readings. Now I read about 2800ppm on the K-1766 but the cell says 1200ppm. Incidentally, this is not the first time the installer have added stuff to the pool without asking me first--I had more-than-SLAM levels of chlorine in my pool for about two days because they dumped a gallon of chlorine in when they did the installations
The TL;DR of all the above is--my salt reading in the cell are significantly lower than the ground truth and I don't trust the installers to handle it so I'm going to wind up fixing it myself. I found the troubleshooting guide from the TFP wiki here, which gives me a couple ideas of how to fix it. I'm making this post to 1) sanity check my plans, and 2) document for other people who run into the same problem.
An easy elimination is that the salt cell is calcified--it's a brand new cell, after all. That doesn't eliminate the possibility of a faulty cell, but at least it's a start.
First plan is to unlock the configuration menu and make sure the thing is configured right. Given just how far the measurements are off, I don't think this is an "Instant average salt level" issue--from what I can tell from the troubleshooting guide, this is supposed to re-calibrate drifts in measurement that happen due to large swings in chemistry or cell degradation, it's not supposed to correct for >2x differentials between measured and actual levels. A difference that big seems more like installer error to me, especially since the voltage/amp readings are negative so I think the stupid thing has wires flipped (the controller seems smart enough to deal with it, but it annoys me when professionals don't bother to do the little things right). Heck they even gave me a little sheet that says the board "doesn't need configured" which I find...dubious given the relative ages of the board and the cell.
After checking configuration, I'll try to adjust the "instant salt level" alluded to above., and see where it goes from there. The issue with this is, the K-1766 measures salt in low resolution and I would prefer to narrow down my uncertainty to less than +/-200ppm it is by default if I'm using it as a gold standard for calibrating my SWCG board. I'm guessing I can just use a larger sample (say, 20 or 40mL) and get more accurate results? This step SHOULD have been done as part of the installation if that's the issue, but well...
I'll update here once I get the thing sorted.
Since the replacement, the system has been giving me "Low Salt" errors, with a salt level that very much disagrees with what I measure using my K-1766 test kit. To make sure I wasn't messing up the test I sent a sample to the company that installed the thing for them to test the salt, and sure enough--the salt level they read was 1710ppm, my reading was 1800, and the display board for the AquaLogic says 700ppm.
I asked the company to fix it, and they dumped a bag of salt in the pool (without asking first) and did nothing for the readings. Now I read about 2800ppm on the K-1766 but the cell says 1200ppm. Incidentally, this is not the first time the installer have added stuff to the pool without asking me first--I had more-than-SLAM levels of chlorine in my pool for about two days because they dumped a gallon of chlorine in when they did the installations
The TL;DR of all the above is--my salt reading in the cell are significantly lower than the ground truth and I don't trust the installers to handle it so I'm going to wind up fixing it myself. I found the troubleshooting guide from the TFP wiki here, which gives me a couple ideas of how to fix it. I'm making this post to 1) sanity check my plans, and 2) document for other people who run into the same problem.
An easy elimination is that the salt cell is calcified--it's a brand new cell, after all. That doesn't eliminate the possibility of a faulty cell, but at least it's a start.
First plan is to unlock the configuration menu and make sure the thing is configured right. Given just how far the measurements are off, I don't think this is an "Instant average salt level" issue--from what I can tell from the troubleshooting guide, this is supposed to re-calibrate drifts in measurement that happen due to large swings in chemistry or cell degradation, it's not supposed to correct for >2x differentials between measured and actual levels. A difference that big seems more like installer error to me, especially since the voltage/amp readings are negative so I think the stupid thing has wires flipped (the controller seems smart enough to deal with it, but it annoys me when professionals don't bother to do the little things right). Heck they even gave me a little sheet that says the board "doesn't need configured" which I find...dubious given the relative ages of the board and the cell.
After checking configuration, I'll try to adjust the "instant salt level" alluded to above., and see where it goes from there. The issue with this is, the K-1766 measures salt in low resolution and I would prefer to narrow down my uncertainty to less than +/-200ppm it is by default if I'm using it as a gold standard for calibrating my SWCG board. I'm guessing I can just use a larger sample (say, 20 or 40mL) and get more accurate results? This step SHOULD have been done as part of the installation if that's the issue, but well...
I'll update here once I get the thing sorted.
