I'm guessing my SWG stopped functioning properly about 10-days ago. Mid last week saw the 2600 reading and added 40# of salt which did not change the salt level. That's when I noticed nothing else happening other than the power light. I cleaned the T-CEL-15 and ordered and replaced the thermistor over the weekend hoping this inexpensive and relatively easy fix would cure my system but no luck. A new cell is on the way (went with titaniumcells.com) since the system is all original equipment installed in 2004. That should arrive today although I am not convinced the new cell will bring everything back to life.
I thought a saw a thread started with similar symptoms from someone opening after winter; but a search of the forum hasn't yielded anything. Also, I've only found one other thread (on doityourself.com) that describes this symptom and they ended up replacing the boards after replacing the thermistor. I am still hopeful for a solution that doesn't require wholesale swap of the circuit boards.
I have been using liquid chlorine to sanitize and had the water tested at Pinch-A-Penny yesterday to ensure I have chemistry correct for new cell.
1.0 ppm FC
120 ppm Total Alk
375 ppm Calcium
90 ppm Stabilizer
3800 ppm Salt
Diagnostics from the Aquarite this morning (temps in Florida dropped into the 40's overnight) are similar to readings since I began troublshooting:
Cold (else 2600)