Water Pump

[tatom]

I want to replace the handpump on our borehole well with an electric pump. This is to water the garden, so an automatic pump isnt necesseary.

The water now is down 3 meters from ground level. The pipe and footvalve with the hand pump is down 12 meters. Most pumps have a suction max of 9 meters. Im wondering if 9 meters is enough? A jet pump can suck 25 meters but my well is only 3 inches in diameter and the 2 pipes wont fit, so thats out.

Ive never run out of water with the hand pump, but I dont know how far, if at all, the water drops during the dry season. Im assuming 9 meters is enough, as all the auto pumps (Mitsubishi etc), have a 9meter max and Ive never heard of wells running dry.

Anyone have any similar situation?

Tom Salarak Khon Kaen

[Artisi]

If the water level is 3 metres below ground level then the lift is actually 3 metres - that is unless the level drops when the well is being pumped. The depth of the footvalve is irrelevant - again unless the level drops in the well to this level.

you need to establish the water level below ground level during a pumping session.

[tatom]

I looked at an Italian made pump with a 1 inch inlet and 1 inck outlet. The booklet that came with it said if pumping more than 4 meters deep, a larger pipe must be used. Whats that all about?

[Boksida]

I looked at an Italian made pump with a 1 inch inlet and 1 inck outlet. The booklet that came with it said if pumping more than 4 meters deep, a larger pipe must be used. Whats that all about?

Less friction loss

[Artisi]

I looked at an Italian made pump with a 1 inch inlet and 1 inck outlet. The booklet that came with it said if pumping more than 4 meters deep, a larger pipe must be used. Whats that all about?

Less friction loss

More friction loss = less capacity or at worst, suction cavitation.

[seedy]

A submersible pump - if available in a 3" diameter, which I think is possible, would serve you well.

No priming issues, and if the water level drops, simply lower the rope to reach the correct depth.

If used to water your garden, and you are watching when you turn the pump on to ensure that water is flowing, will keep the time spent when the pump runs dry to a minimum.

[tatom]

Thank you all,

As I said, the instructions say use a larger size pipe. If the inlet is 1 inch, how much larger should the pipe be?

[Boksida]

Thank you all,

As I said, the instructions say use a larger size pipe. If the inlet is 1 inch, how much larger should the pipe be?

Size counts, so the bigger the better. Find the biggest foot valve that will fit comfortably in your bore casing and use the same size pipe as the connection on that. If your reducer to the pump is in the horizontal plane, use an eccentric reducer with the flat part at the top to avoid air pockets. I would have a tee at the surface of the well with the side connection going to your pump and the vertical part higher than your pump with a plug. You can unscrew the plug and pour water in to your column pipe if you your foot valve leaks and you lose prime.