You absolutely SHOULD enter the square footage, because that is a key part of the calculation / formula. BUT DON’T BE INTIMIDATED… even that part is simple.
On this page…
http://support.rachio.com/article/383-how-we-calculate-water-usage
is a link to this:
Enter your address, draw a remedial box around each zone… it gives you the square footage. Takes 2 minutes.
Once you have that number of SF for each zone, the only other number needed is PR (precipitation rate) - because if you know the RATE that water comes out of the heads… and the size of the area… you’re almost home.
So, what I did of course was log the ACTUAL meter reading before each zone. (mentioned above)
So, meter ended 511.30, then I ran zone 1. After 1 minute of run, my meter read 516.55 - so I ACTUALLY used 5.25 gallons of water, but the Rachio reports 4.155 for the minute. You get this by using the following:
(200 x 2.0) \ 96.25
200 is the square footage… 2.0 is the precip rate listed for MISTER heads… and 96.25 is your constant, explained in the first link above. So, I used MORE water than 4.155. I worked backwards and figured out that my PR was closer to 2.5. Then, just add a new NOZZLE with a PR of 2.5 and assign it to that zone.
Most of mine were very close, but I now have a 0.9 nozzle for one zone… and two zones that I made 1.1 PR nozzles (instead of 1.0 for standard rotor heads)