wow that's a lot of good info! I'm surely scared, but nonetheless we'll have a pool before the end of the summer. I spent the last few days working on the logic for the water level component and i'm getting there. The water level filler will definitely be part of the initial deployment of my module. I've tested with a few switches and it's all working good.
I understand what you mean regarding the valves, but one thing I forgot to mention is that I don't plan to control each and every jet with a valve. I will have a single valve for my pool, one for the spa section within the pool, and one for the kids fountain. That gives me a total of 3 valves for the pool jets, 1 for the water level, and if I want to automate the backwash I would need another 3. Btw, I plan to put a permanent pipe to empty the pool in the sewer (We are allowed to do that here) so this will prevent any flooding in my backyard. Automating the backwash (which I won't do in the initial deployment) will need 3 valves opened/closed on a perfect timing, and some pressure probe to test whether valves were opened properly or not. I haven't figured out this one totally yet but plan to get on it later on.
Lastly, one VERY important component is the ethernet shield. I will fire emails on every specific activitites (water starting to fill in the pool, alarms, etc.) and I've also setup a few security net to prevent any problems (i.e. timer to limit amount of time we're filling the pool in case every water level probes fail).
I've builded a visio workflow to make sure I cover every aspect for each feature. I will share the visio and the initial code when I get a chance.
few problems I have so far: my liquidcrystal screen is limited in the amount of output. 16x2 is not a lot! I'm using an arduino duemilanove and i'm limited in the amount of input pins I have. Any input will be welcome if you guys know how I could do this.
Question for you draythromp, you mention actuator, what are you doing with them ??? moving some kind of ball valves with actuator???-
oh regarding powering 24V valves, I will use an external power supply with enough Watts and use solid state relay to control them.
Thanks a lot for your hints about chlorinator and salts, those are MUCH appreciated believe me! I'll keep you posted on how it goes.