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20

You want to let air into the pipe when you switch the pump off, without letting water out. Here's a few ways to do this. Make a pinhole in the highest point of the pipe. You will lose a bit of water this way, but if it is above the tank, the water will drip back in (provided it doesn't spray too far.) You could even put it just under the tank lid. Install a ...


8

There are two ways to stop a siphon: Put a valve inline with the siphon that simply blocks the flow, "freezing" the state of the system. Flow will resume as soon as the valve is opened again, without needing the pump to re-prime the siphon. Put a valve in the top of the siphon that allows air into the tubing, breaking the suction that keeps the siphon ...


6

An alternative answer which requires no physical action in the system is to move the tank or the garden so that the full water line level is below the level of all of the outlets. You may have to scale up your pump for the additional head required to lift the water. I am also assuming the outlets aren't submerged within the garden after irrigation, since ...


6

How can I stop this water flow without requiring any physical action? You could add in a solenoid valve downstream of your pump that switches off when the pump shuts off. These can be found for a reasonable price online. You should be able to wire it to the same switch as the motor and once de-energized, it will close itself.


5

1) If you have a siphon system, why use a pump? Use a valve to turn the siphon flow on/off. Much cheaper than running a 40W pump. A simple gate valve at the crest will work perfectly in conjunction with a foot check valve at the inlet and another check valve at the outlet to prevent reverse movement of air into the siphon when it is shut off leaving the ...


5

Siphoning works when water goes from a higher point to a lower point, such as from an aquarium on a stand into a bucket on the floor next to the stand. Siphoning only works when the start point is higher than the end point because there is a net decrease in potential energy of the water from start to end, so the system is reducing its total useful energy. In ...


2

Have you tried a gauge guard? It's a simple diaphragm that allows pressure to transmit, without the liquid crossing the barrier.


2

If your pump lifts the water into a hopper, from which it flows under gravity to the plants, this will provide the air gap mentioned in some of the other answers. The hopper could basically be a funnel pushed into the end of the hosepipe. It should be sized and positioned (height) so that it doesn't overflow too much, and over the top of the water ...


2

I think you can create a self-starting siphon if you are able to add pipe to both ends of the "drain pipe." You'd extend the output end downwards until the exit of the pipe is below the bottom level of the ditch. The inlet end of the drain pipe is extended down to the bottom of the ditch (with possible filters, etc). If I got this right, the ditch will fill ...


2

A Venturi pump may do what you're looking for: The pictured pump is for air, but the principle works for water too. There are inline types that don't change diameter from inlet to outlet, but I haven't seen one of this type for use with water. I'm sure it could work for a small elevation gain. For higher head pressures the water jet could be harmful to ...


1

You can buy a mechanical pump that you work by hand for this purpose. It has a cylinder with a piston inside, a suction hose, and a discharge hose. You dip the suction hose into the bilge water, aim the discharge hose overboard, and push the handle on the piston back and forth like a bicycle pump. This is called a manual bilge pump.


1

Figure 1. The solution is to ensure that the pail fill pipe is above the maximum liquid level.


1

The best way to stop the flow of a siphon is to have a shutoff valve inline at the crest. The valve can have a mechanical timer. This will work if an anti backflow foot valve is inline at the inlet and another check valve is inline at the outlet to allow flow in one direction while preventing air from entering and migrating up the long leg. ...


1

How about using two water tanks. Pump sits in tank 1 and pumps twice a day for 5 minutes into tank 2. Tank 2 has the siphon connected and waters the plants via drip irrigation as before. The drip irrigation will only drip as much water as the pump pushes from tank 1 to tank 2 in the five minute interval. The siphon part can remain 'charged' as the water ...


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