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Old June 1, 2016   #72
Worth1
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Join Date: Feb 2006
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Quote:
Originally Posted by MrSalvage View Post
The second one Worth for the ten bucks. Does that one also need to be 18 inches above the emitter?

Also with my emitter being the end of my hose line. (I don't have any emitters yet) Does that change anything? I might need to draw a picture to better explain what I am thinking.

Probably set it up like a vent stack mounted on a 2x4 in the yard.
Okay the first one that is expensive only has to be above ground, this way water can drip out of the bottom.

At any time the pressure on the supply side is lower than the down stream side it will dump water.

It doesn't matter where the emitters are at.

The vacuum breaker can be on a pole as long as it is before the source of contamination (MG do hickey) and around a foot to 18 inches higher than the highest emitter.

As was said the4y have a lot of this stuff at the big box store but you may be miss led or get the wrong thing or junk.
I have bought all of it at one time or another.
The have check valves they sell, these will not work or at least not listed to be used on a system such as yours.
This all seems like over kill but it really isn't considering what can and has gone wrong.

Here is a link that explains the types and what they are used for and why.
I had rather you understand they why and how as to just be lead to the right thing.

Go to the button and they have a list in the subject.
This way you will know and wont be misled at the big box store and get the wrong thing.
http://www.sprinklerwarehouse.com/Ba...nters-s/21.htm
Here they want us to use at least a hose bib vacuum breaker.

I am going to put out one more example as to why and when you would need one.
These examples are in the searches cor cross connection I asked you to look for.

Lets say old Bubba has a big tank half full of hog flop.
He wants to add water to it and fill the tank up for what ever reason.
He is fine as long as he is holding the hose above the surface of the water and hog flop in the tank.

He hears the phone ring and puts the hose in the tank to go answer the phone.
Now the end of the hose in in the hog flop water.

While he is on the phone the water main breaks or his well pump stops and the foot valve fails in the well.
Now all of the hog flop water is going to be siphoned back into the water supply.
So to make it simple these devices are as a last resort back up if all else fails.

I am a huge proponent of back flow devices and the right kind.

I can assure you it isn't just some silly regulation and I am sure they started doing it tears ago because of some bad experiences.
In many case as here in Texas that well may be on your place and your well.
But it is part of an aquifer that covers a huge part of Texas.

Sermon over.

Worth
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