Can I do all this with a new stat and ELK M1

[tmbrown97]

I really don't like the idea of using the water pan shutoff...  that's a last resort to prevent damage to the home and completely overrides the otherwise nice handling of the on/off of the AC - bypasses gentle shutdown, bypasses MOT/MRT - if you were to cut that on then off, I'm pretty sure the unit would act like it lost power then restored (depends on how that manufacturer implements it)... in some cases I think it may even be possible to cut power to the tstats.
 
I would definitely look to do this via rules to the tstats to keep them within cooling ranges, etc... if the special carrier ones can't do it, can you convert to regular tstats and go HAI? I know that was an option with my Trane and I did it... interestingly Trane's high-end custom tstats are OEM'd by RCS, but they're not as tightly integrated as my RCS ZCV which is now unavailable...

 

[dpilati]

I don't like the pan method either but it would work. True that it doesn't seem like something you want to do regularly. 
 
I can set the utility function to shut everything down and then set the stats to not overlap during peak times. My peak would always be 3.5 kw at least. Since I was 3.1 for the first 1/2 of this month with zero automation, that doesn't seem ideal. 
 
Maybe I can find some jumper to control staging separately from the utility function but I am not hopeful.
 
The automation rules to keep the upstairs out of stage 2 would be something like 7pm - 74, 7:30 = 72, 8 pm - 70 and so so until 63 at 9:30. And if it happens to be a little extra hot one night and the a/c doesn't keep up, it would still go to stage 2. It also might shut down on the more mild nights every 1/2 hour. I can't see that being ideal. 
 
Does anyone skip thermostats all together and just use automation and temp sensors?

 

[tmbrown97]

It's doable - someone made one on here out of CAI WebControl I think; and it may be the same person or someone else, but I remember someone on here totally rolling their own 100% custom tstat solution specifically because of Time of Use billing - had a little bit of a homemade feel to it, but they were quite satisfied.    Maybe someone on here can find the links - I don't have time to search right now.