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Topics - DIYguy

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1
I'm noticing that I really would like to have a flow meter on the output of my RJC-100 jet pump, for a variety of reasons.
The timed-bucket method is too slow, and I often am not pumping into an open bucket.
It would help optimize the setting of that brass 'jet-control' screw adjustment.
It would be much easier than trying to infer the flow from the very incomplete pump performance table provided by Red Lion.

I'm just seeking a tapered tube, and the peak pressure of my pump is less than 100 psi.
I assume it would be harder to find one for those deep-well sumbersibles.

If you don't have a favorite, maybe you could suggest niches where i might search around.
I don't need high accuracy, don't want any more electrical units on my pump.
As I am monkeying around with different configurations, I often have dripping fittings, and occasional deluges due to priming, venting, etc.

Thanks,
John

2
I'm wondering about using the Cycle Sensor to run my jet pump (which is refilling a tank) from my low yield well.

Might it be possible to set a somewhat higher threshold than the 'dry run' condition which I abhor due to loss of prime? ( 300 feet of 2" suction, 25 foot well, etc.) My purported 'rationale' follows:
 
At first, the well has recharged and the suction is less negative, the flow rate is higher and thus the current might be higher, (with more water being raised from -5psi to +60)
 
As i draw down the well volume, the suction pressure goes to a more negative value,
 (let's say with the pump discharging through a ~PRV or CSV  into an open tank),
(more work for the pump to raise from -10psi to +60, but the venturi is becoming less efficient faster, and the throughput decreases faster than linearly)

Perhaps the current will  then go down below my elevated 'dry run' threshold, and the CS would shutdown for a delayed restart maybe 15 minutes later, to have less than 100 cycles/day.
If this worked, it would be an adaptive way to cycle the pump which would  not exceed the well yield ,
if I wait long enough between cycles so that the startup flow surge doesn't overpump immediately , in the first 10 seconds.


I'm sold on the Cycle Sensor, but just wondering what to expect from it before I order.
Also, does the Dry Pump detection require current continuously below threshold  10 seconds?
Does the threshold have 'hysteresis', where the current must  first exceed the threshold prior to detecting subthreshold current?

Before I go spend half a day testing, how reflective of  GPM throughput is the jet pump current? I imagine the inefficiency of the jet relative to a submersible would make this approach harder to do with a jet pump.

I'm paying $0.35 for my kwh, so, the intermittent operation seems attractive vs continuous  24 hr operation of a 1 HP jet throttled to 0.75 gpm.
Also, speaking of $0.35/kwh, what is the power supply current consumed by Cycle Sensor unit?
Thanks,
John

3
 One problem is the high leak rate when you are restarting an old dried out tank.

I had some luck with hanging a rainbird sprinkler inside to wet down the whole thing instead of just filling it from the bottom. I had some water in the creek after a big storm and got the tank full  that way,
but,
there are some leaks at the bottom that didn't get better with time.
(where the ones on the sides tended to seal themselves off.
It leaks out 10K gallons in a few days.

I get the impression that maybe at the lowest point in the tank, the rain has been washing through there and maybe washed the tannins out of the wood there?

I enjoyed your tubing-down-the-well sensor for water depth, and hoped you might have some ideas for the tank.

The tank bands are working, but the nuts are rusted in place, and I am not eager to try to get them moving.
I did put a couple of 2inch nylon straps around the tank and winch them down, as a way to reduce the initial leaks.
But when I got it full, the bands were all tight and apparently OK.
I'd really rather not take the bands off if there is any way to avoid it.

I seem to have one leak through the floor, and one at the joint between floor and staves at that low point.
I was hoping to put something in there that would be hygroscopic and swell up, but I couldn't find anywhere I could say was 'the leak'. Maybe I need to really dry it out, like tarp the thing and put a dehumidifier in there...

Thanks,
John

4
Hello;
UPDATED: I spent more time reading and realized I want to ask different questions.
I deleted the old ones as they didn't make much sense in light of what I now understand you have....

 I was going to start by saying I have an unusual situation, but I  then read enough posts to realize the tremendous diversity of situations, and I won't claim to be unusual. I didn't see it covered elsewhere.

Anyway, I have a low-yield 25' well, at about 200 feet above sea level; i.e. usually 29.98 inHg barometric pressure.
It is about 300 feet away from my pump house, connected by a buried 2" Pvc pipe.
I have been using a 1HP Red Lion RJC-100 to pump it.
The 2inch PVC does *not* slope uniformly upwards to the pump, and thus it is a pain(!) to get primed.
There is a foot valve at the bottom of the suction line in the well.

The only way I can avoid overpumping the well (and sucking air, and losing prime) is to restrict the outflow to be up at 60psi. I have been trying to use a (old 1.5") pressure relief valve set at 60, but the setpoint is not very abrupt; i.e. not much difference between 60psi and 63 psi.
I'm still trying to get a good reading on the yield, but I think it is less than 1 GPM.

I also have a bubble trap I can vent , in piping above the jet pump output.
The other key to success is to have the pressure tank sitting at at least 50 PSI for startup;
this ensures the pump gets started without the dreaded 0PSI situation where there is no water in the jet.
Also, having the pressure tank helps make the jet pump more robust against entrained air;
when the pump gets an air bubble hiccup, the tank pressure pushes some water back into the jet pump and it burps and bounces around and then gets back to work. If i have gotten some air in the line, i  can carefully vent it without losing the jet venturi action.

(I haven't explored the lower bound of pressure tank PSI to ensure startup.
Admittedly, the pump stutters  badly initially until I vent some water and it settles down at ~75PSI, ramping down to 60 as the 2inch PVc transitions from +50psi to -10psi.
this is less than elegant... UPDATE; I realize I  need to just bypass the pressure switch on the RJC instead of trying to crank it up to 11ty...).
(At present, when I turn off the jet pump, the entire jet pump goes down to -10psi unless I allow it to suck water back in from the pressure tank).

Anyway, I'm trying to get this rig into a situation where it could operate unattended, and exploit the low-yield resource by filling up my 10K gallon redwood tank. (which presently leaks...)
I need a better PRV with a sharp cutoff, vs. gradual opening above the breakpoint.
It seems that you have this this behavior in the CSV, with the additional feature of the bypass flow.

My UPdated questions;
1. Where can I find data for flow vs. pressure when the CSV is shut, particularly in reverse pressure situations?
(somehow I am dubious that it is 1GPM regardless of differential pressure)
2. How do the smart people utilize the friction loss vs. flow rate data?
( i.e., CSV2  has ~7psi of friction loss at 0 GPM? I don't get that at all).
3. At this point I think I need a CSV (set at ~50Psi (or maybe PRV) to a pressure tank , which has a reverse check valve in parallel with the CSV to allow the suction line to recharge? and also on the pump output manifold, a PRV set to 60PSI which refills my big open tank. The idea of all of this is to insure the jet pump will restart, and then have it's output flowrate-limited to not overpump. (maybe I could add an input check valve, to minimize pressure cycling of my looooong  2inch PVC suction line. This goes against your generic advice of mutiple check valves in a single line.


Right now I have a 80 gal pressure tank, and I can overpump the well  (suck air, lose prime) just trying to get it filled up if it is empty and the well has not recovered any depth.

So, the remote shallow well that is only 25" deep is the source of many headaches.
I am hoping to find a way to keep my jet pump happy without needing an engineer to babysit it, and then use the ~1GPM to fill my big tank, which has it's own pump and hydrant network.

So, the  low yield shallow remote well  requires jet pump operating into a sharp PRV.
 The only way  I see to avoid overpumping is to sit up at the very high  pressure end of the pump curve, maybe 60pSI where zero flow pressure is 63 psi.
Thus, I am grasping at straws, to see if your fine CSV could help me out here.
(I don't seem to find any 1 GPM pumps that can pull from 25 feet down...)
 
So, whadayatink?
John
 I realize the 'reasonable' approach is to get power out to the well, and install one of your Cycle Sensors on a submersible.
Right now that is not feasible.

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