I just purchased the 8-zone Gen2 Rachio. The dashboard is showing “638 Gallons Used”. I’ve only watered for about 90 minutes with drip emitters. 638 not only seems excessive, but it is very most likely inaccurate. Would like to hear feedback and what you think may be amiss. I’d like to have accurate data, which is the reason I purchased the Rachio to begin with. Thanks

# Excessive gallons reported?

**Dub9**#2

I believe this value is just a calculation. If your zone is set to the default 1,000 sq. ft, and the drip emitters are 0.5 inches/hour then

1,000 ft.sq = 144,000 sq. inches.

0.5 inches per hour x 1.5 hours = 0.75 inches.

Volume of water needed = 144,000*.75 = 108,000 cubic inches of water = 467 gallons.

Now spit-balling here, if the efficiency is set at 70%, then 467/.7 = 668 gallons required. Pretty close to your 638 reported.

**anders1212**#3

@dub9 is correct. It is calculating using the inputs in the settings. To help get a more accurate number you can adjust the sqft of each zone. You can also increase your efficiency if you believe that zone is more efficient than the default 70%.

**brkaus**#4

I really think that Rachio should default the area to unset and display no gallons used… or a “-” or something.

This question comes up quite frequently.

You will have to figure out a precipitation rate and area that comes up with proper GPM.

In my case, I got the PR rate from catch cups. I watched the meter for 2 minutes on each zone… and calculated the area from those two numbers. Now my gallons of use is correct (or close anyway).

And does efficiency come into play for GPM? I thought it just increased the runtime.

**Modawg2k**#5

They heavily rely on their total gallons used or saved as part of marketing, so you would think they’d want it as accurate as possible with little customer intervention.

**Dub9**#6

It really is a moving target. If I have 4 heads in a zone, 1" per hour then I will get X gallons. If I have 8 heads in the same area and run for the same period of time, rachio will again estimate X, although twice the water was used.

For me, I don’t care about gallons used as I pul from a lake, and would prefer to worry about green grass. If I was paying by the gallon, then maybe it would be a different story.

Unfortunately, the designers are tasked with trying to make something simple enough for the homeowner that just wants it to not water on rainy days, and yet try to satisfy the micromanager that wants to tweak to 73% efficiency on custom 0.675"/hr. nozzles to get the most accurate usage.

I don’t know if the easier solution would be 2 controllers, or 2 apps for the Simple/Complex or Beginner/Advanced user.

**Dub9**#7

Yeah, and why doesn’t GM call me to ask where I plan on driving my new Impala based so they can put specific tires on based my commute, and also pre-set the radio station to music that I would like…

**brkaus**#8

Once they get the water meter of Gen2 working, I guess it will be automatic (but expensive for the flow meter)

I feel like they should have a setup process that runs all the zones X amount of time with a 1 minute pause between each with someone sitting at the water meter (perhaps in a raincoat :). Enter the GPM directly.

Much easier than expecting someone to do math on PR & area.

Yes, since its part of the marketing, it’s pretty silly that it assumes a fixed area.

**Dub9**#9

You can change the area under each zone. The 1,000 sq.ft. is default, not fixed.

Also, when it comes to marketing, overestimating the gallons used makes it possible to overestimate gallons saved. One rain delay will save 628 gallons of water.

**brkaus**#11

Yup, I know you can change it. But they hid it under “advanced” even though the value directly controls the gallons used on the main page.

In my case, each zone runs over 1k gallons, so its under reporting by default.

**Dub9**#12

Another feature to add to your list: A resettable total.

Like a trip odometer. This is gallon count one can manually reset to compare monthly usage to the water bill, and thus monitor accordingly.

**masterflex**#14

Thanks for all the feedback everyone. This discussion is helping me understand some terms. I still find “Area” confusing though. I have a drip irrigation system and am wondering what “area” is referring to. Does it define the surface area that is being watered (like if you have sprinklers for a lawn)? What is the “area” if say I have 10 drip emitters (0.5 gal/hr)?

Couldn’t my Gen2 Rachio just ask me these questions so the app could easily calculate volume of water used:

- what is the flow rate of your emitter?
- how many emitters do you have?

**Dub9**#15

I spent more time on this than I thought I would.

You are saying your Drips emit 0.5 gallons per hour, and Rachio is assuming 0.5 inches/hour (or .0417 ft/hr).

We know running 10 heads at 0.5 gallons/hr for 1 hour gives 5 gallons.

Rachio calculates Volume as depth * area

Depth is 0.5 inches per hour * runtime.

So, in theory, I believe if your heads drop 5 gallons in an hour at .0417 ft/hr, the area would be: A = 5/0.0417 = **120 sq. Ft**

Testing this, say you had a 20 minute run, 1/3 hour.

Gallons = .0417 * .33 * 120 = 1.65132 gallons

10 heads at .5 gallons/hour for 20 minutes is 10*.5*.33 = 1.65 gallons

Again this is assuming that the 05. gallons/hour is the 0.5 inches/hour Rachio uses.

**masterflex**#16

Thanks for the calculation Dub9. It makes sense. Strange that Rachio doesn’t define “area” anywhere except to say “area must be greater than zero and no more than 10,000 sq ft”. I was still left thinking what area is even referring to.

In order to get accurate enough info, the Rachio controller set up process is a lot more involved than I thought it’d be. Less intuitive than I thought it’d be. I still think an option to simply input the number of emitters and the flow rate, would make it much easier to be done quickly.

Thanks again for the help.