Q: what is the difference in one cell to another if the computer system is the same? in other words, would say an SJ- 45 be the same as an SJ-30 as far as functionality
A: It is often a better value to use larger cell - it just means you have greater sanitation capacity. Your equipment will work less hard to do the same job, so it gets less wear, and then you can boost it to a higher level to create more chlorine more quickly when potential pool problems might arise.
Q: Can I replace my SJ20 cell with a larger SJ40 cell. (2 steps up)? I was able to go up one size but can I do 2 sizes or even 3 using the same wall control unit? How do I tell if the wall controller unit is dead or its the cell?
I run my system wide open 24-hrs a day to get enough Chlorine and I'd like to run it fewer hours.
A: You can use up to the SJ-40 cell without requiring a different control module. A higher capacity system can create more chlorine with shorter run times. If the wall unit shows no power, be sure to hit the "fuse reset button" underneath the unit, and verify input voltage.