Well booster problem with loss of pressure

[bib2210]

Hello everyone
here I made a well of 11 meters deep in diameter 50 mm only for watering
I connected a 20 l pump with booster on it
the pump is 1100 w
the pressure in the bag inside the booster is 2 bar
I have set the pressure to 3.5 bar and it triggers to 2 bar, but the only problem I have is when I open the valve the pressure drops despite the start of the pump and drops to 0 bar
As soon as I close the valve the pressure goes up and the pump stops
the water flow when it is constant
the filter is clean
here I am a little lost

here is my installation

thank you all in advance

[Christophe]

Hello,

To start, a basic question.

On an 11m well it is absolutely essential that the suction line is primed and perfectly sealed (that it remains primed) because no self-priming pump primers over 11m, it is 7 to 8 m in the best case .

So you need a valve at the bottom of the well, do you have one?

[bib2210]

Hello
yes i have 2 check valves
1 at the end of the well and the other at the pump inlet
more water is 1m deep
the suction hose is at 25 and the discharge hose 25 also

[Christophe]

Ok for valve and water level.

So if I understood the problem correctly: pressure ok at stop but strong drop even when the pump is running? That the pressure drops it is normal but that it drops too much it is not.

What is the flow rate at this time in "stabilized" mode (when the pressure is lowest)? To compare with that of the manual .... you must have the flow / pressure curves normally.

How long does it take for it to go up to 3.5 bars? (normally it's less than 1 minute I think).

If it drops, there is not enough water coming into the pump; i.e. insufficient upstream flow = too high pressure losses ...

The suppressor is new I presume (seen the photo)?

Also look at this topic, there are surely similarities with your problem: https://www.econologie.com/forums/probleme-f ... t3853.html

[Gaston]

So if I understood the problem correctly: pressure ok at stop but strong drop even when the pump is running? That the pressure drops it is normal but that it drops too much it is not.

It depends on what is at the outlet: a pump that flows directly outside provides zero pressure (and its maximum flow).

[Forhorse]

What do you call "end of well"?
At the top of the well, or at the bottom?
Because in the photo it looks like it is at the top (and therefore it is not used for much ...)
Are you sure that the valve at the foot of the arm pump is waterproof? (it looks like recuperation ...)

EDIT: +1 with Gaston
And then from 25 in suction it seems to me limit given the length. We should have considered 32 or 40 ...

[Christophe]

It depends on what is at the outlet: a pump that flows directly outside provides zero pressure (and its maximum flow).

Yes of course but I if the pump worked at its maximum flow, there would be no problem so no subject ... I think ...

That's why I asked him to tell us about the flow ...

+1 for the position of the valve if not at the bottom of the well and there is a slight air intake, it is useless to put it on top but good if the water is really 1.5m deep, the pump should self-prime without problem ...

[Gaston]

Yes of course but I if the pump worked at its maximum flow, there would be no problem so no subject ... I think ...

That's why I asked him to tell us about the flow ...

the water flow when it is constant

If it is, there is no problem, just that he worries that the pressure drops to 0 when he opens the valve ...

[Christophe]

Pouted ... maybe!

Constant yes I had read, but is it enough?

[bib2210]

concerning the priming it is done correctly ...