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DogT

Active Member

11

Monday, June 24th 2013, 7:52am

OK, I've got a zone with 6 PGP rotaries in it. With 6 #5 red nozzles, that would be 9.6 gpm if it maintains 30psi, but with the booster I probably have more like 45psi so it should be more like 1.9x6=11.4gpm. Where is the best place to measure psi, before the booster, after booster or at one of the rotaries, I could put a T by one rotary with a gauge on it. I actually wouldn't mind having permanent gauges at the well head before and after the booster.

Just out of curiosity, what would a 1 hp submersible pump do for me over what I have? Would it be more like Dan's system?

I may be out of touch for a while, back surgery tomorrow for herniated disk. I hope it works and gets rid of this pain.

Wet_Boots

Supreme Member

Posts: 4,028

Location: Metro NYC

12

Monday, June 24th 2013, 9:39am

a 1HP submersible drawing at 180 feet isn't going to match what can be drawn from well points with the water only ten feet down

In any event, it isn't likely that the existing system is piped to make efficient use of greater flows.

You could make use of as many as three pressure gauges - one with a "pitot adapter" for field measurements, and two for the booster pump, located on the inlet and the outlet. By logging pressure readings for each of the zones, you can get an idea of what losses are occurring in the field plumbing, and what the original well system is doing, before the booster.

In general, you are probably going to look to reduce zone flows, with the result of raising supply pressures. The reason for this, is that you haven't mentioned that you have any sort of backflow prevention assembly on the system, and correcting that deficiency will cost you some water pressure.

DogT

Active Member

13

Thursday, June 27th 2013, 1:40pm

I have decided to go with a pro pump man. We're talking about a variable speed submersible pump maintaining a 75psi in the house and reducing it for the irrigation right now, but he says we need to figure the problem of the high flow rates at the irrigation and the lower flow in the house somehow. He says he can check the well capacity also. We should have figured this before we even started working on the irrigation side, but the wife was in such a hurry to get it done and of course the irrigation people were more than happy to have her money.

Wet_Boots

Supreme Member

Posts: 4,028

Location: Metro NYC

14

Friday, June 28th 2013, 8:14am

You need to have an RPZ backflow preventer in a sprinkler system that has pipe and sprinklers uphill of the source. Once that is cut into the supply, your worries about excess pressure in the system will change, because the RPZ will subtract 10-15 psi.

DogT

Active Member

15

Friday, June 28th 2013, 8:54am

Nothing uphill of the source, if the source is the location of the booster. If the source is where they tapped into the black pipe from the well, then yes.

Wet_Boots

Supreme Member

Posts: 4,028

Location: Metro NYC

16

Friday, June 28th 2013, 10:02am

Probably need a diagram with elevations to make sense of it all. If your house is at highest elevation, it would have made some sense to supply the sprinkler system from the downstream side of the pressure tank in your basement, and employ the simpler PVB for backflow protection.

DogT

Active Member

17

Sunday, June 30th 2013, 11:12am

I'm sure the pump/well guys will have a field day with the system. Actually it's not terribly out of order, the house is mostly higher than the well head, but downstairs is below it. Some of the irrigation is slightly above the tap into the well pipe, but most of it is well below the well tap point. Most of the irrigation system is below the house including downstairs, but some of it is above the downstairs. I'll report on what I end up with.

I've got 2 guys so far to take a look at the system.

I plan on making a rather detailed story for Angie's List out of this "Irrigation Specialist" which I will also post here.

Wet_Boots

Supreme Member

Posts: 4,028

Location: Metro NYC

18

Sunday, June 30th 2013, 12:28pm

What I don't see, is why a tee was cut into the outside well line, as opposed to drawing from the house, at a point just downstream of the pressure tank.

DogT

Active Member

19

Saturday, July 6th 2013, 12:03pm

The pipe at the well is only 3' deep and at the house about 7'. Plus the well is in a garden where there's plenty of room for all the auxiliary equipment. At the house, it's near the front door. Better away from the house than next to the front door with all that equipment. I'm not complaining about where they tapped into the line, it's only about 60' from the house to the well anyhow.

Still recovering from surgery, but plan is to install pressure gauges at input and output of booster, plus a 1" outlet at the input to the booster. Had a well guy tell me to turn on the water at the input to the booster and let it run until the pressure tank turns on. At this point, the sub pump will probably not keep up and pressurize the tank to 60# again and I should get a good reading of how many gpm right at the output of the well head the sub pump is putting out, at least for the 1" line. If I'm motivated, I'll measure the water height in the well, and let it run for half hour or more and see how much it draws down the head. If the sub pump is only putting out say 10 gpm and the well is supplying 40gpm, there should be minimum draw down I would think.

I'm pretty sure I'm going to get something like a 1 1/2 HP variable speed/constant pressure sub pump. That should put out about 15gpm or so and should solve all my dreamt up issues. At least I should have good pressure in the house which I've never had and it should be able to keep up with any of the zones I have.

One guy quoted me about $3K for the pump and installation.

Wet_Boots

Supreme Member

Posts: 4,028

Location: Metro NYC

20

Saturday, July 6th 2013, 12:50pm

So, your house has no basement utility room with an exterior wall? Where you would have located the pressure tank and pump controls when the place was built?

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