how is air getting in my water hose line??

[Unregistered2013]

i have a centrifugal pump with a 2" inlet and a garden hose outlet (3/4"?) --

it's hooked up to 600' of garden hose -- i know a lot -- but i use it to water my trees.

the weird thing is, one hose-length out, there's nice pressure, etc --

-- but at the end of the 600' run, the water going out "burps" air frequently -- which i tested by putting the hose in a bucket of water, and seeing air bubbles --

-- my question is, how is the air getting in the hose line -- or is it already in there?

how to i get rid of it, and get constant flow?

THANKS!

my dad thinks it's a break in the hose line, letting water out -- and air in -- but that doesn't make sense to me -- why would the hose be sucking air in, if there is a hole??

 

[Bear Foot Farm]

why would the hose be sucking air in, if there is a hole??

The same way a carb sucks gas in.
I think your connections are causing a "venturi" effect, and at least one has a small leak

Venturi effect - Wikipedia, the free encyclopedia

 

[MossRoad]

I tend to agree that one or more of your fittings is leaking. Why don't you try the bucket at the end of the first hose, then the second, then the third, etc... until you find where it is sucking air?

 

[Egon]

Pressure drop due to line friction.

 

[SPYDERLK]

i have a centrifugal pump with a 2" inlet and a garden hose outlet (3/4"?) --

it's hooked up to 600' of garden hose -- i know a lot -- but i use it to water my trees.

the weird thing is, one hose-length out, there's nice pressure, etc --

-- but at the end of the 600' run, the water going out "burps" air frequently -- which i tested by putting the hose in a bucket of water, and seeing air bubbles --

-- my question is, how is the air getting in the hose line -- or is it already in there?

how to i get rid of it, and get constant flow?

THANKS!

my dad thinks it's a break in the hose line, letting water out -- and air in -- but that doesn't make sense to me -- why would the hose be sucking air in, if there is a hole??

Anybody watching the pump ... - Maybe its depleting the supply and taking an occassional gulp of air in. Thats the only thing I can think of that would cause burps in a continuous running flow. A leak at the pump seal, or in your hose line would entrain air uniformly ... so the outflow would spit constantly.
larry

 

[Egon]

There's lots of line resistance and pressure drop. The line pressure has to build up and another blurp of water comes out the end.:thumbsup:

 

[SPYDERLK]

There's lots of line resistance and pressure drop. The line pressure has to build up and another blurp of water comes out the end.:thumbsup:

You are describing flow startup and line purge situation that happens for a few minutes after. After 5-10 max it should be all water unless hes pulling in air somewhere.
larry