## 339 ft

You can only raise a column of cold water in a pipe a maximum of 33.9 ft with a pump in suction lift. Beyond 34 ft, the water will boil or vaporize. This is the reason why submersible pumps and vertical turbine pumps exist. There is no limit to the distance you can push a liquid from below, but you can only aspirate a liquid a maximum of 34 ft from below the pump.

Question: If you put a straw into a glass of milk and suck on the straw, are you really sucking on the milk?

Reply: If you could really suck on the milk, then you wouldn't need the straw. What you're actually doing with your mouth on the straw is lowering the atmospheric pressure inside the straw, so that the atmospheric pressure outside the straw pushes the milk up into your mouth. This is why we say that a pump does not suck. The pump actually generates a zone of low pressure in the eye of the impeller, thereby lowering the atmospheric pressure inside the suction piping. Atmospheric pressure outside the suction piping pushes the liquid up toward the impeller a maximum of 34 ft under ideal circumstances.

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