Efficiency slider use with Custom Nozzle?

I’ve created a custom nozzle type for my Rainbird 5000 rotor head that is closer to 0.75 in per hour vs. the Rachio’s 1.0 in per hour estimate. The reality is my 2 year old water audit shows most of my zones with these rotors at an average of 0.6-0.5 an hour and some as low as 0.4 in hour. For now I have my flex zones set to 0.75 with the custom nozzle and the efficiency at 70% (default.) I plan to reaudit my zones for accuracy then enter those values on a per zone basis but should I then change the efficiency slider to 100% since I know the exact value for precipitation rate in that zone? Thanks!

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Efficiency, or distribution uniformity (DU), I would think very hard to reach 100% unless you have a drip setup.

As far as I know the only true way to measure is to do a catch cup test. If you search our forum or Google you will find a lot of information on that topic.


thanks again for the quick reply.

reading the FAQ it seems the efficiency slider essentially adds run time to a zone beyond the normal precipitation rate of the rotor to account for uneven watering. i have done a catch cup test (with numerous cups per zone) several years ago and i averaged the cups to derive a rate for each of my zones. I intend to repeat the test soon with a longer run time for greater accuracy and will use an average of the lowest value 2 or 3 cups in a given zone. If doing this I have a very accurate estimate of the “worst case” precipitation rate in a given zone wouldn’t it make sense to change the efficiency to 100% to avoid additional wasted run time since my Rachio Iro will very precisely know the worst case rate in each zone which will be accounted for in the custom nozzle value for that particular zone?

Makes sense to me in theory. Nozzle Type (Precip Rate) and Effeciency seem to have the same net effect of changing the duration the zone is watered. @franz is right, 100% efficiency is near impossible to achieve, but if you have your nozzle type set not by the marketing specs for the nozzle but the actual PR you’ve measured via the test you mentioned above, then you could remove the effect Efficiency has on the watering duration by setting it to 100%.

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Came someone comment how they use custom nozzles after measuring their zones outputs with a catch cup test then?

Are you entering the “worst” cup result in the zone and setting the efficiency slider to 100%?

Are you entering the the “best” cup in the zone and then setting the efficiency slider to the percentage difference of the worst cup?

Are you entering the “average” of all cups in the zone and just leaving the efficiency slider at a default of 70% and calling it a day?

Not sure how to tackle this but I will shortly be doing a new cup audit and I have 8 mini marked cups made just for this purpose so I can get pretty accurate.

Have you looked at this support article from Rachio? I’m thinking of doing this also, and the way I understand it is that from #7. on the list, you get the total output of all the cups and divide that by the # of cups you put out. Then #8, multiply by 3 (if you did a 20 minute sample) to get the inches/hr.

Then in step #9 you tackle the efficiency. you are going to find the 25% of your cups that captured the least volume. (in your case it would be 2 cups). Find those cups average volume. Then divide that average by the total average, multiply by 100, and that will be your efficiency percentage.

The Orbit Catch up instructions have some good visuals of how to place the cups.

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