# water softeners and backflow protection



## 1703 (Jul 21, 2009)

From another thread:



Choctaw said:


> Around these parts we must install a double check before the softener, or an RPZ if there is a well on site.


Never heard that before. Can someone explain the need for backflow protection on a water softener? Is the brine the concern?


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## Titan Plumbing (Oct 8, 2009)

That is what the City of Fort Worth explains to me. I'm not to sure I agree, but their opinion is that it could "contaminate" the public water supply.

The only reason I know this is...........? So, I installed the BF preventer and went down the road.


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## 1703 (Jul 21, 2009)

So no dual check on the water meters?


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## LEAD INGOT (Jul 15, 2009)

I ran into a cross connection symptom on a Culligan commercial softner at a McDonalds some years back. It was a clogged venturi in the head, it was causing a fluctuation at faucets. Threw it into bypass and problem went away. Culligan came out and serviced the unit, and all was square with the world. I can see if checks were in place, this symptom would have never arose.


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## Titan Plumbing (Oct 8, 2009)

Colgar said:


> So no dual check on the water meters?


No check valves on meters. Residential only requires DC on irrigation. Commercial requires minimum of DC after meter.


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## MIbassmaster (Mar 16, 2010)

Colgar said:


> From another thread:
> 
> 
> 
> Never heard that before. Can someone explain the need for backflow protection on a water softener? Is the brine the concern?


Backflow on softeners is required because most _installers_ will just stick the discharge line into a p-trap or floor drain, possible cross connection.


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## MIbassmaster (Mar 16, 2010)

Choctaw said:


> No check valves on meters. Residential only requires DC on irrigation. Commercial requires minimum of DC after meter.


 My experience is AVB, or PVB on irrigation, RPZ when chemicals are introduced. Insted of DC after meter, protection should be at _point of use_ (if possible). DC's are commonly used for fire suppression.


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## 1703 (Jul 21, 2009)

MIbassmaster said:


> Backflow on softeners is required because most _installers_ will just stick the discharge line into a p-trap or floor drain, possible cross connection.


Now that I'm not buyin'.

If the drain is done like that no backflow in front of the softener is going to eliminate the cross connection.


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## PLUMBER_BILL (Oct 23, 2009)

MIbassmaster said:


> Backflow on softeners is required because most _installers_ will just stick the discharge line into a p-trap or floor drain, possible cross connection.


I drop the drain tube into a stand pipe but I do this ... Wye branch stays open. Trap at the bottom of riser pipe.


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## Protech (Sep 22, 2008)

That is an "air break", not and air gap. 



PLUMBER_BILL said:


> I drop the drain tube into a stand pipe but I do this ... Wye branch stays open. Trap at the bottom of riser pipe.


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## PLUMBER_BILL (Oct 23, 2009)

Protech said:


> That is an "air break", not and air gap.


Sorry I have to disagree with you on this one ... 

*from WIKI Air Gap = water distribution system ... *

*Air Break = Drainage *

*Granted it is installed on a drainage pipe, but the source is pressured potable water. Therefore it has to be an air gap.*

*Dishwasher air break or air gap? *

*This is open for comments ...*
* 



*


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## Protech (Sep 22, 2008)

An air gap is as the name implies, an free gap of air between the protected disharge and the contaminant source.

An air break, is a chamber with an opening to the air that relieves positve and negative pressures thru the opening.

What you depicted had an enclosed chamber, not a gap of free air.

Any backflow specialists care to make the call?


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## Protech (Sep 22, 2008)

*Air gap (plumbing)*

*From Wikipedia, the free encyclopedia*


Jump to: navigation, search









This article *does not cite any references or sources*.
Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. _(December 2009)_An *air gap*, as it relates to the plumbing trade, is the *unobstructed **vertical** space* between the water outlet and the flood level of a fixture.
A simple example is the space between a wall mounted faucet and the sink rim (this space is the air gap). Water can easily flow from the faucet into the sink, but there is no way that water can flow from the sink into the faucet without modifying the system. This arrangement will prevent any contaminants in the sink from flowing into the potable water system by siphonage and is the least expensive form of backflow prevention.
To further illustrate the air gap, consider what could happen if the air gap were eliminated by attaching a hose to the faucet and lowering the hose into a sink full of contaminated water. Under the right conditions (if the water supply loses pressure and the sink is higher than the point at which the water supply enters the house, for instance), the dirty water in the sink will be siphoned into the water pipes through the hose and faucet. The dirty water then will be dispersed throughout the drinking water system.
All plumbing codes require backflow prevention in several ways. The plumbing fixture manufacturers build the fixtures to meet these codes. A plumber must not build cross-connections in his daily work practices, and Plumbing Inspectors look for improper designs or connections of piping and plumbing fixtures. A common misconception is that a "high loop" (routing a drain line above a sink's flood level, for instance) will provide the same function as an air gap; this is not true, because the continuous connection in such a case still will allow backflow through siphoning.
An air gap must meet the requirements of being two times the inner diameter of the pipe (2*D) in order to be sufficient.[_citation needed_]


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## SlickRick (Sep 3, 2009)

Protech said:


> An air gap is as the name implies, an free gap of air between the protected disharge and the contaminant source.
> 
> An air break, is a chamber with an opening to the air that relieves positve and negative pressures thru the opening.
> 
> ...


Protech is right. 

Air break - is a physical separation used in drainage only.

Air Gap - Is the vertical separation used when potable water system is involved. Vertical separation of 2x the pipe diameter or a min. of 1"


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## littlesis (Oct 18, 2013)

*An air break is not an air gap.*

The air break sounds great but it is not an air gap. The gap should be measured from the highest point that the drain water can stand if the water backs up the drain. If that is a floor drain with a sloped floor, or an area with a flood rim, that point is higher than you would think. The inside wall of the wye also affects the gap distance, water can siphon further with a vertical surface to help wick the water. There are standards for the size of openings on an air gap device, a homemade device may not meet those standards. The simplest air gap is a complete separation of the supply from the flood rim level, raised high enough not to siphon (like a sink and faucet).
The reason you want the air gap is that you don't want to drink sewer water, the brine solution is not the main concern. The brine line is connecting the freshwater system of your home to the wastewater line (used toilet water). The local water system wants to protect their water, but you need to protect yourself too.

Signed,
water system operator, wastewater system operator, backflow assembly tester, pipefitter


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## rjbphd (Feb 5, 2010)

How do you know so much without intro??


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