New Setup - Converting from RainDial

Hey @jeremysm1!
Jumping in here to drop some Flex knowledge. Flex, in my opinion, is how to really take advantage of your controller. The main key to getting it to work for you is to get your zone settings as close to perfect as possible, which you have already done, so you are all set there.
Flex runs off of this idea of Managed Allowed Depletion (MAD). Easiest way to think about it is a gas tank. It watches each zones “gas tank” and once it reaches a certain level (this is defined by your MAD setting) it refills the tank to the top. This promotes deep root growth and creates drought tolerant plants, basically it’s the correct way to water. It uses your zone settings to determine how much “gas” (moisture) your zones are using up each day, and it looks at past and future weather to see if there is precipitation that will help refill the tank. Each zone is handled independently, so if one is running low but all the others are fine, it is the only one that will be watered.
Flex does show future watering days, however it is important to note that these days can change with weather! If consistent watering days are necessary for you it probably isn’t the best option. The duration for each zone will be the same every time it waters.

Warnings for when you first set up: In the beginning flex wants to make sure your tank is full, so it may seem like it overwaters right off the bat. Don’t let it scare you! Also, the calendar can be misleading. It can say it is watering every day, but that is because zones can run independently of each other! Don’t let that rain drop make you think you are watering your whole system that often. Last thing is durations may seem long, but this is because flex changes the way you water. Times should be longer but less often!


Thanks! Flex sounds like the ideal solution. I have a couple more questions:

  1. How do I turn Flex on?
  2. I have 2 zones that apparently only have 1 plant on them a piece. For the life of me, I can’t find the plants on these 2 zones. Should I still set this to Flex? Should I setup the emitters as .5gph, 10 inch roots, and 50 sq/ft so it doesn’t overwater–or do you think I should somehow retire these zones and/or shut them off (maybe pop into a nearby line from another zone)?


You turn flex on by creating a Flex schedule! Check out this article for better instructions: As for the two zones with one plant, that is really strange. In my opinion, you can absolutely still put them on flex, however for your questions on setup I may defer to @Modawg2k or @azdavidr. Is there only one emitter in each of these zones?


My vote would be to get them on another line. I’ve read that if the flow rate of a zone is too low, the associated valve may not turn on and off properly. I might be having that problem myself, which is why I’ve read up on it. If nothing else, it reduces your maintenance overhead for both managing schedules and dealing with a worn valve in the future.


Yeah, 1 plant… 30 plants, doesn’t matter.

Referring to what i mentioned earlier, i would just keep it at default drips as “Emitters”, you can do 10" roots if you want, that’s a bit shallow, but your plants have been trained to be shallow… over time increase it to 15"; and doesn’t matter about sq feet, it has no impact on how much water the Rachio will put out, it’s used purely as an estimated number of how many gallons your Rachio used… 50sq ft would be an overestimate for 1 shrub

If you don’t mind doing the work, it’ll reduce the risk of leaks since you are decreasing the number of used lines out there.

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Thanks! I just setup the Flex Daily watering schedule. The hard part was finding that area of the app (Edit Water Schedule, then clicking on the plus icon on the top right)–that was tricky as I kept overlooking that plus sign! I setup the time to start at 6am, that way I can visually see it in progress on mornings (when I remember) and spot leaks or problems before I leave for the gym or work.

I’m going to further troubleshoot my zone4 and zone6 to see if I can find what’s on those segments. My hope is to end up turning those zones off altogether leaving me with 3 zones (bigger trees, front yard, back yard). I’m guessing the next step also is to track the measurement of water via the Rachio app versus actual usage on the city meter.



Question: believe it or not it rained pretty hard and long here in Scottsdale last night. I have the flex daily schedule setup and it seems like it knew to push the watering schedule back several days. How can I check that it actually did that? Also, how do I check how much rain the local weather station received? I just want to see how to make sense of it all. Thanks!

Go to a zone, click on the moisture graph, and you’ll see the graph on November 3rd reflect a slight increase due to rain. Hit the More Detail button and you’ll see how much it accounted for preciptation. My system accounted for 0.24 inches yesterday.

Very neat! Here is a screenshot of mine. Got .18 inches of rain. What is the moisture balance supposed to be at? At what amount will rainfall affect the schedule?

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When your level drops to the “Allowed Depletion” line, the system will water. You can follow the math easily with the details expanded like you have in the screen shot. Basically you start out with the day’s (we’ll use yesterday the 3rd) current soil moisture level, your soil was at 0.48inches…, you didn’t add any Irrigation (which would add to your moisture level) , but it did rain (0.18in added to your moisture level)… then you minus off how much water is used by the plant and environment (Crop Evatranspiration, 0.11 inches… this number will be much higher when it’s hot out vs cold days). and the final day’s Moisture Balance is a the bottom, which is then carried over to the next day’s top number.

Click the arrow next to the Nov 4th at the top and you’ll see the watering predictions for the next 7 days based off weather forecast

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That is so cool! Thanks for explaining. Here is a screenshot of the next watering time for that zone—seems like my system is setup and operating as it’s supposed to.


Your graph along with watering amount (0.55) look pretty consistent with what I’m seeing on my setup here in North Phoenix so I would say you are looking good. Once you starting seeing how the system works like this, then you can get into tweaking like perhaps makea custom nozzle for each zone, etc.

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So far, nothing seems to be dying and the watering schedule seems to be working! I still haven’t had time to start hunting for those little used zones, but that’s on my list. Here is my newest focus: when logged into the Rachio app (or web page) I can see how much water we used in the last month. How is that figure being calculated? For instance, I never told the system how many emitters we have per line. I know someone suggested turning off all water sources in the house, and turn one zone on at a time and make a note of the city’s water meter at start/stop of a cycle to know for sure how much water it uses.

But how do we get the Rachio to be programmed so it displays about the right amount on that dashboard? Thanks!

The amount of water is figured as rate of nozzle (e.g., 0.5"/hr) multiplied by the time run and by the area for the zone. For example, 0.5"/hr x 1 hr x 12000 sq ft gives 500 cu ft (3740 gallons).

I have some follow up questions:

  1. How did you go from 12,000 sq/ft to 500 cu/ft? I can find a cubic feet to gallons calculator but have no clue how you got to 500 cu/ft? My front yard zone is like 2000s/ft for instance.
  2. Most of my watering is soley for plants and not grass. So the area calculation above couldn’t be accurate. I am covering 2000 sq/ft for instance, but may just have 30 desert plants on it. In the back I might cover 2000 sq/ft but have 100 plants on it. (all with say .5 gallon emitters)

Would be great if there was way to simply count the emitters and their gallons and plug that figure into the Rachio manually. In the meantime, is there a conversion to use? For example, 30 x .50 gallon/hr emitters on a zone would equate to how many sq/ft?

  1. 0.5"/hr * 1 hr equals 0.5" (or 0.5/12 feet) water depth times 12,000 sq ft yields 500 cu ft.

  2. Rachio uses the area you input and the watering rate in in/hr. This is something folks on drip systems have to back figure for the gallons used to approximate the actual. For people on sprinker heads (like me), get the rate, efficiency and area right, and the gallons will be close.

Your magic formula works out to be:
Area = total rate (gal/hr) * 12 / [emitter rate (in/hr) * 7.48]

If you have 30 0.5 gal/hr emitters and the default 0.5"/hr, the formula becomes
Area = 15 *12 / (0.5 * 7.48) = 2692.8 sq ft. (You can check my numbers using my prior example.)

@jeremysm1 If you want to improve this calculation, @azdavidr created this calculator that should help!


Also switched from Rain Dial Plus 6.
Everything is working great!
Do I need to do anything with the black Earth Ground wire?

@Hal3 - The Rachio doesn’t have a ground port, so there is no place for it to go. As green is the normal color for a ground wire, I might either remove the black wire entirely, if it will come out easily, or cap off the black wire with a wire nut (even though there is no voltage as someone might confuse it with a wire that has current) and push it back in the hole out of the way.

Welcome to Rachio.

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Thanks for the reply!
I did get it working just as you suggested.

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