Hunter pgp ultra rotors -- time is wacky

All of my rotors have the blue 1.5 nozzle in them. Is it safe to say I need to create custom rotors in rachio with a .3in/hr rate? The default rotor is set for 1in/hr.


Yes, create a custom rotor for .30 inch per hour. I have Toro T5P-Rapid Set and I customized my precipitation rate at .6 inch per hour. Rachio needs to take a look at the default precipitation for rotors. The 1 inch is too high for typical 3/4" inlet rotors.

Thats what I was thinking but then when I set a zone up to use the custom rotor, it wants to run it for 2 hrs and 5 mins in my flex schedule. I have 9 zones of rotors, I cant have each of them running for two hours! Any thoughts?

Do you know your awc to be correct?mmif it is, that is what it takes to get a proper deep watering.
You could verify that you have better head to head coverage than that chart indicates by conducting a catch up test.
If this is on a flex daily, I bet you end up with 1 o2 zones that run on each day, so if you are worried about a hours in 1 shot, it probably will not be that long each time.
I have 1 inch / hour heads, but I get to amotorize my soak times.

I cannot comprehend rotors running for 2 hours a zone. Warm season turf requires about 1 inch per week, with cool season turf 1.5 to 2" per week in more normal areas of the country. Perhaps this is just a one time thing. My rotors on cool season grass tend to run 20 to 25 minutes every other day with even day watering. Something is not right. With your precipitation rate at .3 inch your run time in July should be around 40 minutes or so.

Well, his,root depth is at 6 inches, his awc is at .17 his pr is .3 inches and hour
So rachio needs to put down 6 * .17 = 1.02 inches of water = 3.4 hours to fill the zone from empty to full.
Since mad is at 50% 3.4 * .5 = 1.7 hours, which is 105 minutes. Now that we have an efficiency of .7, 105 *1.3 = 136.5 minutes.

Doesn’t seem unreasonable to me.

Guess so if you are filling a root zone with hypothetical zero soil mousture. Still a lot of water!

Its incredible. This flex schedule would run for ~19 hours

I guess you overlooked where I reduced it to the deplition level. I 3.4 * .5. So it’s really trying to apply 1.7 inches.

Well, if anything I would swap the nozzles to .35, that is the rate the soil will absorb so time is being thrown away.

Honestly installing some 1 inch an hour and letting soak intervals work while other zones are running would probably be best. You get to leverage water’ elasticity to apply a bit more than can be absorbed. And let it soak.

Could you elaborate a little for me? What should I do? Thanks!

If he switches to .35 pr heads you can shave off 23 minutes a zone.

right now i have it set to 1in/hr rotor and it runs for 37 mins. If I set it to .35in/hr custom rotor, it wants to run for 2+ hrs and I have 9 zones of rotors…

I don’t know about our area being considered ‘normal’, but to echo @plainsane 's point I have a PR or 0.4"/hr, root depth of 8" & AWC of 0.12. That gives me 8 * 0.12/0.4 = 2.4 hrs. With the 50% MAD and 0.8 efficiency, I water for 2.4hr*0.5/0.8 = 1.5 hours. If my PR were 0.3"/hr like his my time would be 2 hours. This, and my grass is hardly lush. Of course it’s a desert …

I would move up to the .5 heads will get you to 1 hour 35 minutes. Really it’s 1 hour 5 minutes but you will have a soak so another zone can run.

Your pr for the zone should be .3, don’t change that, the model will skew, this skew will continue to compound.

What I’m trying to tell you is that, your irrigation must run that long based on the data you have presented. You can sacrifice root qualit by shorter more frequent applications by artificially inflating your pr, but this is rarely desirable.

Take a,look at this guys post, he has pics of doing it wrong to doing it right, all on flex daily, living in satans butt crack Watering strategies to fix this bad area

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ok, keeping my pr at .3 for the 9 rotor zones still puts my watering time at around 18 hours. Im on a well and cant come close to that. whats the best alternative?

@Dkd114 How long were your run times before, and what was the associated duration?

When I was choosing the default rotor of 1in/hr it would run for 37 minutes every 4-5 days. Once I found out my nozzles are really only putting out .3in/hr, I brought up this discussion

How long were you running that way ? How long have you had the Rachio and what was the watering like before ? I’m trying to understand what your lawn has been trained to see up to recently.