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j_nolesfan
03-24-2007, 11:13 AM
Hello All,
I'm excited to find such a great source of information. I'm in Pensacola, Florida (Northwest tip of Florida near Mobile, AL). I'm currently installing a DIY lawn irrigation system. I plan to use Hunter PGP rotors and probably Rain Bird rotor/spray heads (can't remember the model) as well as some bubblers for my flower beds. The system will have about 34 rotor and or spray heads. I have a well that's 160 ft deep with a 1.5 HP pump and a 50 gal. pressure tank. I intend to use 1.25" or 1.5" sched 40 for my mains and 1" or 3/4" for my laterals. I plan to have all valves (1" valves, not sure which brand yet) in a single manifold near the well tank. With that being said, I measured the GPM by running the well tank at full open via the 1.25" valve outlet for about five minutes, then catching the water via 1.25" 10' pipe into a 5 gallon bucket. The bucket filled in about 10 seconds on several tests. I don't think well pump water recovery will be an issue. Here's where I get into trouble. When calculating my zone sizes based on about a 30 GPM flow rate at an honest 30 PSI on the pressure guage when the 1.25" bypass valve is at full open, I'm not sure if I should favor being under 30 GPM or slightly over. The static pressure of the tank is around 80 PSI. If I run a garden hose to an ordinary oscillating Melnor sprinkler from the spigot on the same leg as my pressure guage, the pressure stays at 85 PSI all day long. I know other things need to be considered like pressure loss in the pipe and general PSI but I'm mainly worried that even with a 50 gal pressure tank, I may put undue stress on my well pump if I don't maintain a 30 GPM flow rate.

One final question, if I feed the zones in basically a "goal post" patter where I run a main line to the zone and "T" it off with one direction serving half of the heads and the other serving the rest, should my "lateral" (everything past the "T") be 1" (1.25" maybe)? I know that the last two heads on each leg should be connected with 3/4". I plan to have around 8-10 heads per zone of Hunter's PGP rotor heads with an output between 2.8 and 3.4 GPM.

Thanks in advance,
Jeff

j_nolesfan
03-24-2007, 11:31 AM
I don't see the edit button but I need to add that the longest main line run will probably be 150 feet with no more than two 90 degree elbows in it. It will also flow down a grade of about a total 18" drop over the 150' length.
Thanks again,
Jeff

Wet_Boots
03-24-2007, 12:19 PM
You have to do your 'bucket' test with a pressure gauge upstream of the discharge valve, and with the pump running continuously (no cycling) - only then can you collect useful data, combining flow and pressure.

By the way, in some areas (probably not Florida) it can pay to run a pump for an hour or so while testing, in case it's one that can run dry.

j_nolesfan
03-24-2007, 02:58 PM
The well running out of water is the least of my worries. I'm in a subdivision where the well driller has installed several wells. He knows the area and none of the others have complained about running dry for their systems. The bucket test was done with the pressure guage immediately upstream of the discharge valve. It's part of a metal T that has one leg running into the pressure tank and the other running to two ball valved outlets.
Thanks,
Jeff

j_nolesfan
03-24-2007, 03:04 PM
Again, is it better to exceed the capacity of the pump flow or to keep the output at less than pump capacity? Also, are 1.5" Sched 40 mains good from the valve (located at the pressure tank, centrally) and running as much as 140' before splitting via a T to two different legs roughly forming the shape of a football goal post. After the T, are 1" lines ok with the exception of the leg between the last two heads of each side of the "uprights"? Or, should I stay with 1.25" and drop from 1.25" down to 3/4" when I get to the last two on each leg?
Thanks again,
Jeff

j_nolesfan
03-24-2007, 03:27 PM
In other words, as for capacity, would it be better for a 30 GPM system to feed a 33-35 GPM capable zone or to feed a 23-25 GPM capable zone?
Thanks,
Jeff

Wet_Boots
03-24-2007, 03:41 PM
You have to match the flow of the pump. There isn't one side or another to lean on. This is where interchangeable sprinkler-head nozzles come into play.

I suspect your 'drawdown level' isn't anywhere near 160 feet, if you're actually getting 30 gpm from a horse-and-a-half pump, while sustaining at least 50 psi at the pressure tank. (you have not yet supplied any "Y gpm at X psi" numbers yet - do make sure you have them, since they will guide you in pipe and valve sizes) ~ A quick look at a performance curve for a high-capacity submersible pump makes the 30 gpm figure suspect, unless the actual water level in that well is close to the surface. You really want to take the time to build your own performance curve. In the absense of experience, you do better to go by the numbers.

LCPullman
03-25-2007, 11:45 AM
Check out this link http://www.irrigationtutorials.com/sprinkler04.htm If you read it through and follow the directions, it should answer your flow question.

The wet test method would carry on from the info you have, You could do both the dry and wet method just to verify your results.

You should go with the bigger lines, 1.5/1 as opposed to 1.25/.75 The larger pipe combination with enable you to minimize pressure loss through the pipe.

At 30gpm you should either run 1.5" globe valves or 1" angle valves. The standard 1" globe valve will have too much pressure loss.

j_nolesfan
03-25-2007, 02:21 PM
You have to match the flow of the pump.
Does my pressure tank not serve as a buffer to allow the pump to cycle on and off and run at full output at all times? Does the pressure tank not smooth out the pressure delivered from the system so that it's consistent? I'm asking honest (maybe they're dumb?) questions. It was the only reason I had a tank installed in the first place.
Thanks again,
Jeff

Duekster
03-25-2007, 02:32 PM
Even as a DIY project I would get a professional design even if I did it through Rain Bird. Check on-line for this service on their website.

Also, many reputable Irrigation guys get pretty decent discounts so they might actually do the job for slightly more than what you can do it. Lot less headache and maybe better performance.

I think you should do your home work, I love informed customers because they weed out the guys who do shoddy work.

j_nolesfan
03-25-2007, 03:41 PM
Ok, getting as close as I could to the wet method, here are a few measurements.

It just so happens that my current setup is almost identical to what Jess Stryker describes as his wet method. I have a 1.25" pipe coming from my tank that has the pressure guage in it. The guage is about a foot from the tank and the ball valve is about a foot from the pressure guage.

First, let me say that my pump cycles off when the pressure reaches about 85 PSI. I can maintain several pressures up to a little over 70 PSI without the pump seeming to catch up and shut down (for at least five minutes at each level suggesting that it's not going to catch up or the pressure would have increased, right?). My 5 gal bucket is just a little over 5 gals, more like 5.2 gals.

At 72 PSI, I fill the bucket in 16 seconds. According to my scale, that's about 18.75 GPM (19 GPM is safe considering the fact that it's over 5 gals).

At 50 PSI, it takes 13 seconds, 23+ GPM

At 30 PSI, it takes just over 10 seconds, about 30 GPM considering

It seems I can maintain any of these flows at their respective PSI levels without cycling the pump. If I get close to 75+ PSI, the pump seems to catch up and shut down quickly.

Does this help at all?
Regards,
Jeff

LCPullman
03-25-2007, 04:08 PM
Ok, getting as close as I could to the wet method, here are a few measurements.

It just so happens that my current setup is almost identical to what Jess Stryker describes as his wet method. I have a 1.25" pipe coming from my tank that has the pressure guage in it. The guage is about a foot from the tank and the ball valve is about a foot from the pressure guage.

First, let me say that my pump cycles off when the pressure reaches about 85 PSI. I can maintain several pressures up to a little over 70 PSI without the pump seeming to catch up and shut down (for at least five minutes at each level suggesting that it's not going to catch up or the pressure would have increased, right?). My 5 gal bucket is just a little over 5 gals, more like 5.2 gals.

At 72 PSI, I fill the bucket in 16 seconds. According to my scale, that's about 18.75 GPM (19 GPM is safe considering the fact that it's over 5 gals).

At 50 PSI, it takes 13 seconds, 23+ GPM

At 30 PSI, it takes just over 10 seconds, about 30 GPM considering

It seems I can maintain any of these flows at their respective PSI levels without cycling the pump. If I get close to 75+ PSI, the pump seems to catch up and shut down quickly.

Does this help at all?
Regards,
Jeff


Ok, you probably should aim for around 60 to 50 psi which would put you around 20-23 gpm. At this point, you need to make sure you don't go under 19gpm, because that is where you can really wreck your pump (by cycling it). So, you should probably aim for around 22 gpm per zone.

The pressure tank on your system will work to maintain pressure for normal house usage, but doesn't help alot with the quantity of water you are dealing with.

The tutorials have alot more basic info about design of your system, here's the index page http://www.irrigationtutorials.com/sprinkler00.htm

j_nolesfan
03-25-2007, 04:24 PM
Ok, you probably should aim for around 60 to 50 psi which would put you around 20-23 gpm. At this point, you need to make sure you don't go under 19gpm, because that is where you can really wreck your pump (by cycling it). So, you should probably aim for around 22 gpm per zone

Thanks. In effort to do this, I'm adjusting my heads. In some cases, I'm stepping down from a PGP head to a PGJ and using a longer range nozzle to dispense more GPM. Of course, I have to take into account the precipitation rates as well. At this rate, it shouldn't take more than 15 minutes to water my front lawn :laugh:

Wet_Boots
03-25-2007, 07:02 PM
I would be using a 30 gallon garbage can for the flow testing, and possibly have the cut-out pressure a bit higher. If you have a 100 psi tank, you could do this. If you have a large property, you may have room for heads that throw over 40 feet. You're on the border of needing larger supply pipe and inch-and-a-half zone valves.

j_nolesfan
03-26-2007, 09:43 AM
Good suggestion on the high flow/high throw heads. I'm going to try and put the highest pressures in the back yard so that I can dump more water back there if necessary. In this case, would it be a good idea to go ahead and step up to 1.5" mains? If so, and my valves are centrally located at the pressure tank, are 1.5" valves necessary? Would I be cutting my own throat if I used 1" valves? The next question is, would/could I step down to 1" lines at my first T? If so, I'd only use 3/4" where I branch a single head off the main or where I'm running between the last two heads on a leg, right? I'm asking because I'm about to pull the trigger on a pipe order.

My final questions, (hopefully) when I get the system together, do I have a little time to adjust the flows by using different nozzles before I do any damage to my pump? Say for example that my pump cycles on a zone because I'm not dumping enough water. that's not a real issue as long as it's addressed within a couple of weeks, right? Of course I'm referring to levels within reason. If I was only dumping 10 GPM, I'm sure it wouldn't take long before the pump got tired of that and said uncle.
Thanks,
Jeff

LCPullman
03-26-2007, 11:40 AM
You don't want to be running more than 19 gpm in a 1" pipe and you don't want more than 11 gpm in a 3/4" pipe. A 1.25" would be sufficient for running up to 30gpm. but I tend to recommend going for larger pipe because you lose less pressure (psi) as you travel distance.

A 3/4 is certainly big enough to go to one head or the last couple heads. as far as 1" at the first Tee, that is probably ok, you really need to figure out how aprox how much water will be flowing each direction.

Go to the friction loss calculator on this page http://www.irrigationtutorials.com/sprinkler09.htm and put in your numbers to find out how much psi you would loose in your pipe. Add it all up and see what kind of pressure you will have at your sprinkler heads.

When it comes to valves, the valves I use (irritrol 2400/2600) have the following presure loss numbers: with a 1" globe valve, you lose around 3.5 psi at 20+ gpm. With a 1" angle valve you lose around 1.9 psi at 20+gpm. On the 1.5" valve (hunter ICV) you loose about 1.5 psi at 20+psi. However, many 1.5" valves are more like 3 psi loss (Hunter PGV). I think that 1.5" valves are not essential, on one of my systems, I would probably use a 1" angle valve.

j_nolesfan
03-26-2007, 12:13 PM
Thanks LC,
I ended up going with 1.5" pipe for the mains and 1" for the laterals. Considering my max output is 30 GPM at 30 PSI, I can't imagine where I'd be above 15-20 GPM after my first T off of a 1.5 down to a 1". So, that should be ok. Now, back to pressure/friction loss. If I figure a zone at say 22-25 GPM at about 50 PSI and then factor in friction loss of roughly 7 to 8 PSI (crossing one valve, running through 1.5" main no more than 150', one 90 degree elle and ending in a T that takes me to a 1" leg in two directions), does the pressure loss equal the need for more PSI meaning I'm effectively getting less GPM at a 50 PSI pressure at the manifold (before the valve)? If so, does that translate into a perceived higher GPM rate as far as the pump is concerned? I just need to understand the relationship of pressure loss and flow rate as far as the pump is concerned. I'm mainly focusing on the fact that I need to stay over 20 GPM. In a couple of zones, that's tough, especially when the sprays and bubblers are concerned because they provide specs for 30-40 psi max. I think everything else will be ok, even if I have to put a high flow nozzle on a head or two to raise my output.

As for controllers, I'm looking at the Hunter XC-600 outdoor controller which leaves one extra zone open. The Pro-C is nice, I suppose but I don't like having to add 3 zones right out of the box considering I'll probably never need the sixth one to start with.

Back to the valves, is there enough difference between the Irritrol 2600 and the Hunter SRV101G 1" w/ flow control to justify using one over the other? I assUme the Irritrol valve will work with the Hunter controller just fine.

Thanks again,
Jeff

Wet_Boots
03-26-2007, 12:45 PM
Sprays and bubblers are available in pressure-regulating models, so over-pressure won't be a problem. As for valves, you want valves with flow controls. Too useful to do without. As long as you are running at less than 20 gpm, you won't have any issues with one-inch valves.

By the way, you want to have a backflow preventer on the system. On flat ground, a pressure vacuum breaker will do. Since BP's can handle high flows, a one-inch PVB will handle any flow the pump is giving.

Don't worry about any cycling at first. Careful measuring and design will minimize or eliminate that. In any event, a pressure tank of the proper size will protect you from worrisome short-cycling.

j_nolesfan
03-26-2007, 03:01 PM
As long as you are running at less than 20 gpm, you won't have any issues with one-inch valves.


That's part of the issue though Wet Boots. I'm keeping my valves at a central location. So, I'm going to be running 22-27 GPM through the valves. Does that mean I need to go bigger on the valves? The price really jumps when going from 1" to 1.5" as far as I can see. I'm thinking it's like three times the price for a 1.5" vs a 1".

Also, a pressure vacuum breaker? Even if I'm basically dedicating the system to irrigation? It's not going to be connected to the house water. I guess that's the next thing I should read up on, huh?

j_nolesfan
03-26-2007, 03:24 PM
One other question, slip connections vs threaded on control valves. Do they go bad often enough for me to need to worry about being able to unscrew them? Next question, how do you unscrew the pipe if the other end is threaded in the same direction or if it's cemented into the next junction? Just cut the pipe, unscrew and put a coupling on the cut? I guess I talked myself into that one, if I can get it.

Wet_Boots
03-26-2007, 03:39 PM
As far as backflow on a dedicated irrigation well goes, you are running into regional differences here. The water you're pumping is the property of Florida, and they can tell you to protect the source, if they want to. If you run at higher supply pressures (and lower gpm) that will reserve some pressure for backflow to be added at a later date. In most states, if any part of your well plumbing is in your house (pressure tank, maybe) then they consider it domestic water to be protected, and you don't get an opportunity to claim it's anything different. A 1-inch PVB is rated for flows up to 50 gpm, so you don't have to break the bank to get backflow protection.

One idea on valves - with flat ground, and the valves grouped next to the house, you might use antisyphon valves. That gives you backflow protection, and flow control valves, all in one package. An Irritrol 2713APR can handle flows to 30 gpm (8 psi loss at 30 gpm) - Hunter and Rainbird also make antisyphon valves (with higher pressure losses) - These are one inch valves, and priced accordingly.

Mike Leary
03-26-2007, 03:44 PM
One other question, slip connections vs threaded on control valves. Do they go bad often enough for me to need to worry about being able to unscrew them? Next question, how do you unscrew the pipe if the other end is threaded in the same direction or if it's cemented into the next junction? Just cut the pipe, unscrew and put a coupling on the cut? I guess I talked myself into that one, if I can get it.

It's toss-up to glue or to thread valves, we've NEVER had a valve body go.
If the body goes, you have to cut it out anyway. Some of the commercial
boys put unions on. If you are carefull with glueing, I'd have no problem,
tho old habits die slow.....probably the rain. Remember to turn 1/4" when
gluing.

Mike Leary
03-26-2007, 04:03 PM
It's easy to get either rector-seal or glue into the valve & givin' you fits in
the port...carefull.

j_nolesfan
03-26-2007, 05:41 PM
Thanks Mike and Wet Boots. The single vacuum breaker is probably cheaper than five anti-siphon valves, wouldn't you agree? As for pressure vs flow rates, I'm actually pushing hard to make sure I dispense enough water in at least two zones. If I'm capable of 30 PSI and 30 GPM with my 1.5 HP pump, I probably shouldn't dispense less than 20 GPM and even at 20 GPM, my pressure is well above 50 PSI at the manifold where all of my zone valves will be. I just don't want to burn up my pump. As a reminder, I have a 50 Gal 100 PSI pressure tank that cycles the pump off when the pressure reaches 85 PSI.
Thanks again,
Jeff

j_nolesfan
03-26-2007, 05:48 PM
Would something like a Febco 710F 1.25" Atmospheric Vacuum Breaker work? Here's a link: http://www.usabackflowproducts.com/index.asp?PageAction=VIEWPROD&ProdID=1147
Thanks,
Jeff

j_nolesfan
03-26-2007, 05:59 PM
Oh, one more thing, I can get Rainbird 5000 rotors for $7.02 or Hunter PGP rotors for $9.88. I've read good things about the 5000 on this site. Any reason why I should pay more for Hunter? I'm buying like 25 of them so it does make a difference. I can get Hunter Prospray 4" popups for $1.63 or the Rainbird equivalent for $1.29. I suppose quality is king there, which one is better?
Jeff

Mike Leary
03-26-2007, 06:01 PM
I'm going to bring my Airstream Motor Home down there and throttle you
if you use anti-siphon valves. As my mentor once said about backflow :
"any unit you can test is a "assembly" the rest are "devices" & junk".

Mike Leary
03-26-2007, 06:05 PM
Oh, one more thing, I can get Rainbird 5000 rotors for $7.02 or Hunter PGP rotors for $9.88. I've read good things about the 5000 on this site. Any reason why I should pay more for Hunter? I'm buying like 25 of them so it does make a difference. I can get Hunter Prospray 4" popups for $1.63 or the Rainbird equivalent for $1.29. I suppose quality is king there, which one is better?
Jeff

Either/or on the rotors. Rain-Bird 1800 king of the hill. Add Weather-Matic
brass nozzles & you'll be stylin' I'm not going there on 1804/1806 issues.

j_nolesfan
03-26-2007, 06:06 PM
I'm going to bring my Airstream Motor Home down there and throttle you
if you use anti-siphon valves. As my mentor once said about backflow :
"any unit you can test is a "assembly" the rest are "devices" & junk".

I guess that means I'm going with a PVB? :confused: :drinkup:

Mike Leary
03-26-2007, 06:33 PM
What's the deal with you cheapskates not using DCVA assemblies?

Wet_Boots
03-26-2007, 06:39 PM
The single vacuum breaker is probably cheaper than five anti-siphon valves, wouldn't you agree? As for pressure vs flow rates, I'm actually pushing hard to make sure I dispense enough water in at least two zones. If I'm capable of 30 PSI and 30 GPM with my 1.5 HP pump, I probably shouldn't dispense less than 20 GPM and even at 20 GPM, my pressure is well above 50 PSI at the manifold where all of my zone valves will be. I just don't want to burn up my pump. As a reminder, I have a 50 Gal 100 PSI pressure tank that cycles the pump off when the pressure reaches 85 PSI.
Thanks again,
JeffBrass PVBs are only going up in cost, and the AS valves are holding pretty steady. No brass. As much as some practitioners will decry them, they are close to standard issue in California. I use them on retrofits more than new work. AS valves replace the underground zone valves. Probably about five bucks more per valve, compared to standard zone valves.

Forget the '30 gpm at 30 psi' reading. That isn't enough pressure to be useful. Rotor heads want at least 40 psi, and the larger nozzles are designed for 50 psi. Since you figure to lose at least 10 psi from source to heads, you can expect to be running at 60-70 psi source pressure. A bit less for sprays and bubblers.

I'm going to bring my Airstream Motor Home down there and throttle you
if you use anti-siphon valves. As my mentor once said about backflow :
"any unit you can test is a "assembly" the rest are "devices" & junk".Just remember, Vacuum Breakers, PVB's, and antisyphon valves, all work by gravity. Ask a practitioner (or mentor) that uses, say, Double Check Valve Assemblies, if they can be counted on as much as gravity. :drinkup:

Mike Leary
03-26-2007, 06:39 PM
O.K., I can hear the torches being fired off....if you have no backpressure,
you're fine with a PVB.

j_nolesfan
03-26-2007, 06:43 PM
Mike,
Call me confused. I guess I misunderstood from the beginning on the PVB and ASV issue. Let me say that my well and tank is higher than any part of the surface of my entire lawn. The lowest part is about 36" lower than the well. Please, spell it out for me.
Thanks,
Jeff

Mike Leary
03-26-2007, 06:44 PM
I figured boots would step in on this....I respect your input. Isn't California
going to all R.P.B.A ?

Wet_Boots
03-26-2007, 07:04 PM
Irritrol AS valves
http://tinyurl.com/yvrg9ghttp://tinyurl.com/2qg7c5Backflow is one of the aspects of sprinkler work that shows regional differences. Strictly for the money, AS valves are the best choice. Highest level of protection (toxic rated) - no valve box to dig, since the valves are above ground. Easy access to the valves for service and adjustment.

And yes, they aren't beautiful. California has backflow and sprinkler stuff in plain sight, and no one looks twice at it any more. Other states can be a different story. But there really isn't much of a question about backflow standards trending towards toxic-rated devices. This seems to be a one-way road.

(by the way, the Febco 710 is an atmospheric vacuum breaker. Different animal. You'd need five of them, one for each zone)

Mike Leary
03-26-2007, 07:16 PM
I've seen AS valves running up the side of a house to take into the height
of highest head.....well, I look at it!

Wet_Boots
03-26-2007, 07:25 PM
I've taken advantage of some tall landscaping to hide AS valves and PVBs - I feel ever so good when the shrubbery screen gets cut down (not) ;)

Mike Leary
03-26-2007, 07:28 PM
I feel your pain.

PurpHaze
03-26-2007, 09:32 PM
What's the deal with you cheapskates not using DCVA assemblies?

As Boots is so fond to point out there are regional differences (some are even municipal differences with neighboring towns) as to what backflow codes are in affect. I realize you Washingtonians are into DCVAs but the correct answer on any backflow question is, and always will be, "check your local codes." :)

PurpHaze
03-26-2007, 09:44 PM
When it comes to valves, the valves I use (irritrol 2400/2600) have the following presure loss numbers: with a 1" globe valve, you lose around 3.5 psi at 20+ gpm. With a 1" angle valve you lose around 1.9 psi at 20+gpm. On the 1.5" valve (hunter ICV) you loose about 1.5 psi at 20+psi. However, many 1.5" valves are more like 3 psi loss (Hunter PGV). I think that 1.5" valves are not essential, on one of my systems, I would probably use a 1" angle valve.

Love it... someone else who understands the pressure loss differences in Irritrol angle vs. globe configuration valves. I'm assuming you also understand the rated GPM capacity of that manufacturer as well? :clapping:

We use the Irritrol Century Plus valve and I often have people ask (1) "Why do you use angle configuration?" and (2) "Why are you installing a 2" valve on a 3" inlet and outlet (lateral) and running 120 GPM through that valve instead of just installing a 3" valve?" I hand them the specs and tell them to figure it out themselves. Experience, knowledge and ability to read a manufacturer's specification charts separates the men from the boys. :laugh:

j_nolesfan
03-26-2007, 10:33 PM
Ok, note to self,
Check codes to be sure on the backflow issue. If they do apply to my case.
1. 1" angle valves with a single AVB installed is first option if so.
2. 1" AS Valves is second option.

If no codes apply to dedicated irrigation pumps then 1" angle valves it is.
Sound like a plan?
Jeff

Wet_Boots
03-26-2007, 11:00 PM
Option #1 is a waste of an atmospheric vacuum breaker. They cannot function if they are continuously pressurized. Look at the AS valve, and see that they combine an angle valve and an atmospheric vacuum breaker in one unit. Downstream of the control valve is where the AVB functions. One for each zone. Upstream vacuum-breaking requires a single (more expensive) PVB.

Be prepared for the future. Even if you shined on the backflow for now (and with inexpensive AS valves available, why would you?) it might be required in the future, so make sure you are prepared for the additional pressure loss.

LCPullman
03-26-2007, 11:11 PM
[QUOTE=PurpHaze;1767876]Love it... someone else who understands the pressure loss differences in Irritrol angle vs. globe configuration valves. I'm assuming you also understand the rated GPM capacity of that manufacturer as well?/QUOTE]

The 2400/2600 are rated to 30gpm. Right? The 1" Century Plus and the 1" 700 series have pressure loss ratings up to 50 gpm, but the pressure loss numbers get rather high above 30gpm.

LCPullman
03-26-2007, 11:21 PM
Strictly for the money, AS valves are the best choice. Highest level of protection (toxic rated) - no valve box to dig, since the valves are above ground. Easy access to the valves for service and adjustment.

And yes, they aren't beautiful. California has backflow and sprinkler stuff in plain sight, and no one looks twice at it any more. Other states can be a different story. But there really isn't much of a question about backflow standards trending towards toxic-rated devices. This seems to be a one-way road.

Do you mean to say that the AS vavles are better than a DCVA? In my town, the AS vavles are looked down on by code enforcement in favor of the DCVA. If you actually have chemical danger, you have to install a Reduced Pressure Zone Assembly.

Wet_Boots
03-26-2007, 11:28 PM
AS valves are toxic-rated, and DCVA's are not. Toxic-rated is better. RPZ are toxic-rated, too, and the only toxic-rated choice when actual backpressure exists.

sprinklertech
03-27-2007, 05:52 AM
I don't think rainbird's rotary sprays are available yet. They were on recall a couple years back, problems with the orifice. I have recently used walla walla rotary sprays and find the performance a lot better. Also, these type are adjustable.

Hank Reardon
03-27-2007, 08:59 PM
I thought I saw the RB stream rotors at Horizon last week. We use/like the MP's for certain applications (down with the 1000's).

PurpHaze
03-27-2007, 10:46 PM
I thought I saw the RB stream rotors at Horizon last week. We use/like the MP's for certain applications (down with the 1000's).

I was out at Ewing today picking up four WVCs and spoke to the guy handling the irrigation bids from various contractors. He stated that the original design on two new elementary schools was 50 valves and a gazillian spray pop-ups with all the accompanying wiring, etc.

They redid the design using MP-Rotators in a lot of places and eliminated 12 valves and thousands of dollars. I won't be around for the opening of those school sites in a couple of years though. :)

Sure wish they'd try a 2-wire decoder design as I'd like to see one in action before I go. Maybe I'll change an existing system over before I leave. :laugh:

Mad Estonian
03-28-2007, 01:59 AM
Maybe I'll change an existing system over before I leave.

There you go, sticking it to the taxpayer again. I would love to install a 2-wire system, that definitely looks to me like way of the future (well, I guess wireless technology might be around the corner too).

AS valves are toxic-rated, and DCVA's are not. Toxic-rated is better. RPZ are toxic-rated, too, and the only toxic-rated choice when actual backpressure exists.

Our local purveyor is doing away with ASVs, everything will have to be DCVA (not retroactive though, for now). Is it your code locally that the ASVs have to be 6" above the highest head? That's supposedly the case here, but never remotely enforced. Maybe I'll start retrofitting all my customers' ASVs on 1 or 2 foot risers. I could tie a nice little trellis to them and grow a clematis or something, lovely little garden feature. Of course, there was that valve I once spotted, after looking around for a while, installed up in the rafters of the garage by the original DIY homeowner (an engineer, nonetheless). About 9 feet up in the air. Wasn't an ASV, but would of had ample clearance. Another valve in the same garage was right below the controller, a few inches away from an electrical outlet. Free Estonian rye bread to the first one who can tell me what's wrong with that picture. Or you can order yourself something similar here http://www.balticshop.com/cgi-bin/item.cgi?item=2053&cat=0801&title=Latvian_Rye_Bread.

PurpHaze
03-28-2007, 08:27 AM
Maybe I'll change an existing system over before I leave.

There you go, sticking it to the taxpayer again. I would love to install a 2-wire system, that definitely looks to me like way of the future (well, I guess wireless technology might be around the corner too).

Considering that a school site is in constant flux with portables being brought in or removed all the time and other things such as play boxes, basketball courts, etc. either being added or removed the versatility of 2-wire expansion capability would be a tremendous advantage. :)

MrH117
03-28-2007, 11:15 AM
I don't know beans about irrigation but I did stay at a Holiday InN Express last night.....Take a look at the MP- Rotator line of heads.....High efficiency and operate on lower gallonage....they should be great for matched precipitation.