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Discussion starter · #41 ·
As I said, use the faucet. If you want to crunch the numbers to determine the pressure loss in the pipe due to friction and elevation changes between the faucet and the valves next to the house, then do it.
Thanks, the zones down by the house are down hill from the outside faucet. I would think the pressure loss would be much if it's going down hill. I might be wrong on that.

Going right now to check the pressures. I don't have a faucet down by the house that isn't regulated. I do want to have accurate numbers the best I can.
 
Thanks, the zones down by the house are down hill from the outside faucet. I would think the pressure loss would be much if it's going down hill. I might be wrong on that.
No, you are not wrong. There may be no pressure loss, or even a net gain.

Going right now to check the pressures. I don't have a faucet down by the house that isn't regulated. I do want to have accurate numbers the best I can.
Without knowing your flowrate, the measurement is essentially worthless.
 
Discussion starter · #44 · (Edited)
Ok guys here are some more numbers.

Before I started got the outside yard Faucet pressure: 72 psi. Also, after I was done testing the zone pressures and all zone were off, the pressure at the outside faucet was down to 64 psi.

Zone 1: 60 psi.
Zone 2: 52 psi
Zone 3: 44 psi
Zone 4: 40 psi
Zone 5: 40 psi
Zone 6: 44 psi.

Took pressure from faucet on house and pressure was 64 psi. Turned on Zone 2 and the pressure didn't change.

Without knowing your flowrate, the measurement is essentially worthless.
Flowrate of the system isn't that what I was calculating when I was at the meter determining GPM/Zone?
 
Discussion starter · #47 ·
Don't know. What's the margin of error?

Zone 1 - 10 GPM @ 60 psi.
Zone 2 - 15 GPM @ 52 psi
Zone 3 - 20 GPM @ 44 psi
Zone 4 - 20 GPM @ 40 psi
Zone 5 - 25 GPM @ 40 psi
Zone 6 - 25 GPM @ 44 psi.
Hey man. Sort of stuck now. Not sure what the margin of error would be or how to calculate it. Never thought this would be so hard to figure out.

Needs to be an R.P. in this case.
Thanks.
 
Hey man. Sort of stuck now. Not sure what the margin of error would be or how to calculate it. Never thought this would be so hard to figure out.
Does your water meter read in GPM and are there any published specs you can refer to? Based on what you have provided, it looks to me like the measured flow is +/- 5 GPM.

If you want your system to perform as it is right now, then your pump needs to provide x GPM @ y PSI +/- margin of error at your faucet.

Have you measured the dynamic pressure at your most distant point yet?
 
Discussion starter · #49 ·
Does your water meter read in GPM and are there any published specs you can refer to? Based on what you have provided, it looks to me like the measured flow is +/- 5 GPM.
Yes, reads in GPM

If you want your system to perform as it is right now, then your pump needs to provide x GPM @ y PSI +/- margin of error at your faucet.
If I can get it to perform as it is now, that would be great.

Have you measured the dynamic pressure at your most distant point yet?
No. Could you explain to me how to go about doing that?

Do you know for a fact that you can't get by with 35 psi at the highest elevation?
Boots quoted this. Looks like I'm about 40-45 psi at the highest elevation, if I'm reading my numbers correctly.
 
If I can get it to perform as it is now, that would be great.
Then I would be looking at a pump that could provide 30 GPM @ 50 PSI at your faucet. Note, some of your numbers gives me reason for concern with regard to system performance.

No. Could you explain to me how to go about doing that?
Pitot gauge or an inline stem adapter is the easiest way, assuming your most distant point is a sprinkler or rotor.

Appropriate tools should be self-evident

http://www.hunterindustries.com/product-line/tools
 
If you plan to be at this location in the long term, then it's time you invested in making the system into something that both works and is code compliant. I don't even have to know where you live to state that you need an RPZ device to isolate city water from lake water. Nothing else will do. At given that they cost so much, you only install one of them if at all possible. That means you have only a single connection point for the system. These devices have a significant pressure loss, and may require you to re-nozzle some of the heads to get the coverage you want. You want the existing system to be functional with a minimum of pressure, because you can only get so much from a pump that has to push the water uphill as much as 120 feet.

You should do this work first, and then remeasure your system consumption, with the pressure gauge connected at the RPZ. (and if you claim you will sever the connections and remove the pipes, rather than to pay for an RPZ, I have a bridge to sell you for cheap)
 
Discussion starter · #53 · (Edited)
If you plan to be at this location in the long term, then it's time you invested in making the system into something that both works and is code compliant. I don't even have to know where you live to state that you need an RPZ device to isolate city water from lake water. Nothing else will do. At given that they cost so much, you only install one of them if at all possible. That means you have only a single connection point for the system. These devices have a significant pressure loss, and may require you to re-nozzle some of the heads to get the coverage you want. You want the existing system to be functional with a minimum of pressure, because you can only get so much from a pump that has to push the water uphill as much as 120 feet.

You should do this work first, and then remeasure your system consumption, with the pressure gauge connected at the RPZ. (and if you claim you will sever the connections and remove the pipes, rather than to pay for an RPZ, I have a bridge to sell you for cheap)
Boots, Yeah those RPZ are expensive. I do plan to stay at this location for awhile. I installed the current sprinkler system and it wouldn't be to big of a pain to just disconnect the city water from the current sprinkler system until I have more funds to buy a RPZ. Here is another picture of how the main water line runs. Looks like I would have to buy two RPZs.

Then I would be looking at a pump that could provide 30 GPM @ 50 PSI at your faucet. Note, some of your numbers gives me reason for concern with regard to system performance.
May have to look at buying another pump and sell the one I have.

Pitot gauge or an inline stem adapter is the easiest way, assuming your most distant point is a sprinkler or rotor..
I look into these. I guess I could also remove the highest sprinkler head and rig up something to connect the pressure gauge I already have.

Handwriting Font Parallel Drawing Rectangle
 
Since you can't trust the performance of a pump that has to raise the water 120 feet, you need backup, and your only affordable backup is city water, unless you have no problem with plants dying if you don't water them by hand with a garden hose. You have to be realistic here. If you cheap out and are caught, you might wish you had never seen a pump in your life.
 
Ouch! Someone screwed-up on the install. In my area, they would call for "premises isolation", which means a approved backflow assembly AT THE METER. That brings up a problem with an enclosed system, water heater especially. Second problem is contamination from chemicals introduced from the irrigation system into the household potable system. It might be cheaper to start over. :cry:
 
Discussion starter · #57 ·
Since you can't trust the performance of a pump that has to raise the water 120 feet, you need backup, and your only affordable backup is city water, unless you have no problem with plants dying if you don't water them by hand with a garden hose. You have to be realistic here. If you cheap out and are caught, you might wish you had never seen a pump in your life.
Point well taken. If I disconnect having the capability to use city water then I'll be hosed. With the numbers I have posted should I be looking a storage tank and use the pump I have to fill it and then get a smaller pump to pump the water from the storage tank to the sprinkler system? Seems like I'm on the boarder line of the pump I have not working. Or should I look at getting a bigger pump? I got this pump from my neighbor...It had a bad bearing so I'm not out much on the pump. I also might want to figure in if I want to expand the current system at some point.
 
Discussion starter · #58 ·
Point well taken. If I disconnect having the capability to use city water then I'll be hosed. With the numbers I have posted should I be looking a storage tank and use the pump I have to fill it and then get a smaller pump to pump the water from the storage tank to the sprinkler system? Seems like I'm on the boarder line of the pump I have not working. Or should I look at getting a bigger pump? I got this pump from my neighbor...It had a bad bearing so I'm not out much on the pump. I also might want to figure in if I want to expand the current system at some point.
a approved backflow assembly AT THE METER .
I have an approved backflow assembly at the meter (bought it from the city water department) and also have them were the main water line connects to the sprinkler system.

If that driveway is paved, you have a big headache no matter what, if heads and valves are in the 'island' .
Yep, driveway is paved but I ran 4" conduit before it was paved.
 
If you have enough sleeve space under the driveway, you can add a mainline pipe to allow you to have one single connection point for the system, at which you have the RPZ, and yes, you have the RPZ, because you want the option to run on city water if need be. Trust us on this.

Strictly for the money, you stick with that SSHM-2 pump. It probably costs more than everything else put together.

Now, we have that pump curve, with its limit on total height of water at 210 feet, assuming you can rework the zones to use 15 gpm or less - for more flow, the pump delivers less pressure

Again, strictly for the money, you look to see how you can make the system work with less flow and/or less pressure. You do this after the mainline rework and RPZ install. With a pressure gauge on the RPZ itself, you can partially close the system shutoff valve and see how low you can bring the pressure and flow. You may get to a point where you can run on the pump output, and maybe only need to change a nozzle or two.
 
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