Built in Backflow preventors

[sheshovel]

Hey,is the device on a freezeless sillcock a backflow device?I know it keeps water from backflowing into the bib so it won't freeze,but does this give any backflow protection like an
added device would?They are called backflow preventors also are they really?
Say I am installing a batt opp timer,filter,W press Reg, and drip system coming off one of theses bibs,do I also need to add a back flow device on these types of bibs?I have been but do I need to?

[Wet_Boots]

A sillcock with a vacuum breaker is not adequate for any sprinkler protection, since the sprinkler valve(s) you add negate any upstream atmospheric vacuum breaker function. Make your battery operated valve an anti-syphon type, if elevation works in your favor. Otherwise, in California, it would be time for an RPZ.

[sheshovel]

I'm talking a drip system here.

[Wet_Boots]

And what makes you think drip is any different from regular sprinklers, when it comes to backflow prevention? A cross-connection is a cross-connection.

[bicmudpuppy]

Hey,is the device on a freezeless sillcock a backflow device?I know it keeps water from backflowing into the bib so it won't freeze,but does this give any backflow protection like an
added device would?They are called backflow preventors also are they really?
Say I am installing a batt opp timer,filter,W press Reg, and drip system coming off one of theses bibs,do I also need to add a back flow device on these types of bibs?I have been but do I need to?
That device is called an "atmospheric vacumn breaker" or AVB. An AVB is not rated and becomes ineffective if any type of valve is installed downstream of the AVB. Anti-siphon valves are the same type, and some of those california manifolds you see incorporate a mastervalve. When they do this, they eliminate the compliance to code that the anti-siphon valve provided. For your described situation, either a PVB or RPZ should be installed and can be fed by the hose bib, but you cannot consider the AVB of the hose bib to be an effective backflow if you put a valve in past it.

[sheshovel]

Ok this is how I have been hooking them up--
freezeless sillcock-
PVB valve,filter,
water pressure reg 25psi-
batt/op timer usually Orbit 6015-
line adaptor and then out with my dripline.Is this correct as long as it is 1'above my highest emmitor?
Also I have a problem with the PVB valve and WPRREG dripping water onto the timer and gettting the batteries wet when they relieve pressure and stop bck flow when the unit shuts off .I have no way I know to install a regular valve from these set ups because they only stick out of the wall a tiny ways.In fact they are so close to the wall,I can barely get teff tape around the threads of the bib.

[Dirty Water]

I can barely get teff tape around the threads of the bib.

Why are you putting teflon on hose thread? Hose fittings do not seal on the thread, they seal on the O-ring in the female fitting.

I'm with Wet Boots on this one. You need to start installing RPZ's (since DC's aren't allowed in Cali???)

Personally (since I'm still allowed to use a DC), if I have to come off a sillcock, I'll use a 3/4" brass 45 with a hose to pipe thread adapter attached to Lee Valleys excellent brass Ball valve Y. Thread that onto the sillcock and align it so it points down towards the ground. Then I use a sch 80 nipple to drop below the ground and elbow into my doublecheck.

Then it goes off to the valve, pressure reducer and fitler and back up to the drip line.

This is much cleaner, the customer still has a hose hookup, and theres no junk hanging off the house.

Lee Valley Valve (Not my picture):

http://bluenose.cps-ecp.org/tip/watercrossfeednew.jpg

[Wet_Boots]

I think the 'backflow protection' part of those frostproof sillcocks is more like a vacuum relief valve (Ever see a sprinkler system with nothing but a brass vacuum relief valve for backflow protection?)

I mentioned the RPZ for cases where you might be running the drip uphill from the house. They do make 1/2 inch RPZs that cost less that the usual. If you were on flat territory, and all you were doing was one zone of drip, you might feed it through an antisyphon valve that has the solenoid replaced with a battery-operated one, such as Rainbird sells. I see they even list an assembled combination of 3/4" inch antisyphon valve, 200 mesh strainer, and 30 psi regulator.

[sheshovel]

OK thanks guys!I appreciate the replys.So what I am doing is not good?Great Idea Holland ecept alot of these are over cement driveways,no way to get underground.I will take some pics today to show you what I mean.

[Wet_Boots]

Unburied, I suppose nothing is going to really look good. I would always try to have everything but the sillcock connection as regular pipe, either threaded or slip. I'm sure any brand-name battery-powered solenoid operator will cost more than an Orbit battery-powered valve, which is why I thought trading a PVB for an antisyphon valve would make economic sense. Another way to get proper backflow in your setup, assuming flat ground, is to have an atmospheric vacuum breaker right after the Orbit valve, which would meet the requirement of not being under pressure 24/7. Richdel used to offer just the AVB portion of their antisyphon valve, and Hunter lists an AVB in their catalog. And there are the classic brass AVBs, which could be had in a more-economical 1/2 inch pipe size.

[F6Hawk]

If I am understanding what you mean correctly, you are talking about a hose bibb (sillcock) that sticks out of the side of the house, right? If so, and it is a freezeless model, then there is no type of PVB that I know of. The way they work (at least around here) is that the sillcock is like a foot long, and when you turn the handle to shut it off, the actual sealing takes place at the inside part of the pipe, not right at the handle, like conventional faucets. This allows the water to drain out of the device, and keeping the shutoff seal that far inside the walls allows the heat from inside the house to prevent freezing.

So in this case, putting anything downstream of the shutoff seal would render the freezeless part inop, and as far as I can see, would provide no backflow prevention at all.

If I misunderstand the device you are referring to, I apologize in advance, but this is how the freezeless bibbs work around here.

[Critical Care]

The frostproof, or frostfree sillcocks can come with or without an integral vacuum breaker. Picture of one below with the antisiphon.

I'm with the rest of the guys here. I think what I'd do would be to "Y" off of the sillcock - and JonHolland shows a nice brass Y - and then one way or another adapt and neatly run poly or something else down and over to someplace appropriate to install the RPZ, regulator, timer, and other widgets.

[sheshovel]

F6Hawlk yes that is what It is.
Critical care that is exactly what I am speaking of.The pic is what I am dealing with so OK will do as advised.
Thank you all very much! RPZ's it is!
P.S. someone told me that they WERE backflow preventors in the freezeless sillcock...WRONG INFO there huh!

[Dirty Water]

WRONG INFO there huh!

I've only been doing this two years, and if I had a dime for every bit of wrong info I've been told, I wouldn't have to do this.

[bicmudpuppy]

F6Hawlk yes that is what It is.
Critical care that is exactly what I am speaking of.The pic is what I am dealing with so OK will do as advised.
Thank you all very much! RPZ's it is!
P.S. someone told me that they WERE backflow preventors in the freezeless sillcock...WRONG INFO there huh!
An AVB is a backflow preventer. It just isn't rated for the application here. Once you put a valve past an AVB, it can no longer function properly as a backflow.

[sheshovel]

OH Well.dosent freeze that hard there anyway,what other choices do I have then?

[Wet_Boots]

Do you have elevation in your favor, so you can locate a vacuum breaker (used downstream of the control valve, in accordance with the codes) higher than the drip lines?

[GrazerZ]

Just did a little 3 zone system here. we used the sill **** as requested by the customer. As per the ok of the plumbing inspector, I use a vacuum breaker on the sillcock, cost me $4.00. Just remember,I called and asked first. I always make sure and would rather not do it than do it against code.

[Wet_Boots]

Your plumbing inspector does not know the codes he's supposed to enforce, but you probably already knew that. California writes their own rules, and they're probably tougher than any other state's. Nowhere on the planet Earth can a single atmospheric vacuum breaker provide backflow protection for a three zone sprinkler system.

[Dirty Water]

Your plumbing inspector does not know the codes he's supposed to enforce, but you probably already knew that. California writes their own rules, and they're probably tougher than any other state's. Nowhere on the planet Earth can a single atmospheric vacuum breaker provide backflow protection for a three zone sprinkler system.

Perhaps he used a pressure vacuum breaker and not a AVB?

[Wet_Boots]

A PVB? For four dollars? Sign me up. I'll take thirty-three pallets.

[Dirty Water]

A PVB? For four dollars? Sign me up. I'll take thirty-three pallets.

Hehehe..

I missed that part of the post :)

[GrazerZ]

It is what it is, sorry if you don't like it. I called, thats all I'll say about it.

[Dirty Water]

It is what it is, sorry if you don't like it. I called, thats all I'll say about it.

Its not that he doesn't like it, its just that an atmospheric vacuum breaker will not work with a constant pressure line downstream of it.

EVER.

You need to use a Pressure Vacuum Breaker, A doublecheck or a RPZ.

[sheshovel]

It is what it is, sorry if you don't like it. I called, thats all I'll say about it.

He's not making a judgement he's giving you factual important info that you had better listen to.....,regardless if the plumbing inspector said it was OK on the phone.
he was not on site to actually inspect the set-up
that makes YOU responsible if someone should get sick or die from backflow into the household water system.You can say "Hey I called and asked" but that wont hold up in court if you get sued by the homeowner cuz his kid or infant got sick because of faulty uninformed work done by you.
He may of missunderstood you or did not know what he was talking about
but you can rest assured that these guys DO know what they are talking about.So if I were you I would listen and fix that job the way it should be done,to protect the homeowner and his family not just to follow what some diphead tells you on the phone.

[sheshovel]

Do you have elevation in your favor, so you can locate a vacuum breaker (used downstream of the control valve, in accordance with the codes) higher than the drip lines?

Yes I do most of the time and that's what I have been doing,or if I can I will go off another bib and run a stub out and bring the line up to a new bib to get it higher.
But sometimes there is a cement walkway on one side and the drvway on the other side no way to get it in the ground.This is a brand new mnfctred home park so there are alot of these.It was just too hot to take my camera out with me today or I would have pics for you.

[GrazerZ]

Its actually called a "hose bib anti siphoning valve", my bad. As for you She shovel, you have a way of frequently piping in a "yea what he said". I was trying to simply add to the discussion what I have been locally alowed to do. I'm not interested in a lecture. I do use RPZs. No I don't claim to know everything. its funny though how now that you have your question awnsered, you feel the need to judge others. Whatever. :rolleyes:

[Dirty Water]

Its actually called a "hose bib anti siphoning valve", my bad. As for you She shovel, you have a way of frequently piping in a "yea what he said". I was trying to simply add to the discussion what I have been locally alowed to do. I'm not interested in a lecture. I do use RPZs. No I don't claim to know everything. its funny though how now that you have your question awnsered, you feel the need to judge others. Whatever. :rolleyes:


Going back to what was said above. Anti-Syphon valves only work if the line after it is not a constant pressure line.

I'm sure the inspector you spoke to on the phone did not realize that you were going to put more valves downstream of it.

But hey, go ahead and endanger your clients. Its only a little lawsuit.

[Wet_Boots]

Installing correct backflow protection is a basic CYA concept. And if you do want to CYA, you politely listen to any incorrect information you may receive from the municipal officials who can say pretty much anything without repercussion, then go ahead and do the right thing, even if it costs you more in time and material. For a three-zone job on flat ground, fed by a hose bib, individual antisyphon zone valves could have been used, for very little additional money.

[sheshovel]

Not judging you at all Grazer,and you are very wrong about me "just piping in to copy what someone else has said or go"What he said"I was trying to let you know that there can be problems with what inspectors will tell you over the phone,if in fact you take that advice or not is not my worry so be it,but you just judged me not I you...so get that streight.


Now You guys have confused me..An AVB can't be used After a valve (or downstream of a valve )or it renders it useless correct?
But OK I am now totaly confused sorry

[bicmudpuppy]

Not judging you at all Grazer,and you are very wrong about me "just piping in to copy what someone else has said or go"What he said"I was trying to let you know that there can be problems with what inspectors will tell you over the phone,if in fact you take that advice or not is not my worry so be it,but you just judged me not I you...so get that streight.


Now You guys have confused me..An AVB can't be used After a valve (or downstream of a valve )or it renders it useless correct?
But OK I am now totaly confused sorry
The AVB must not have a shutoff valve AFTER it. The valve must be upstream of an AVB. That is essentially what an anti-siphon valve is. It has a built in AVB after the valve.

An Atmospheric Vacumn breaker relies on gravity for it to vent. In a pressure situation (valve down stream) it is possible for the vacumn breaker to NOT vent and the flow to be reversed. For example, your drip zone is not running, and there is a fire next door. When the fire department hooks in and creates the necessary flow to produce suction from your customer's meter, an AVB under pressure will allow the flow to reverse and not vent. If the AVB is floating on an open line, and the pressure reverses. the AVB will fall and vent. And yes, this means that every garden hose nozzle out there defeats the vacumn breaker on the hose bib.

[Wet_Boots]

Even though an atmospheric vacuum breaker (and an antisyphon valve, as well) is rated for toxic backflow, you will sometimes find local ordinances prohibiting their use. Given their past and present mis-application, I can understand local disapproval.

Getting back to the original drip irrigation, and how to connect to a hose bib, I would look to thread a hose adapter into a brass tee, and work from there.
<img src=http://img328.imageshack.us/img328/1949/hosebibconnection29vw.jpg>

[Dirty Water]

Not judging you at all Grazer,and you are very wrong about me "just piping in to copy what someone else has said or go"What he said"I was trying to let you know that there can be problems with what inspectors will tell you over the phone,if in fact you take that advice or not is not my worry so be it,but you just judged me not I you...so get that streight.


Now You guys have confused me..An AVB can't be used After a valve (or downstream of a valve )or it renders it useless correct?
But OK I am now totaly confused sorry

An AVB will not work if the line after it is a constant pressure line. You need to use a PVB in that scenario.

EDIT: Didn't realize theres another page, Bryan and 'Boots beat me to it :)

[sheshovel]

Ok so this is how I am going to do it,or them.Tee off the freezeless silcock witha 3/4"galv tee.Install a reg hose bib of one side of the tee,then run a hardline off the otherside to a place where I can bring up a drip hook=up and do the following..3/4"adaptor onto line,a threaded 90,nipple,batt-op timer,AVB,or RPZ,filter,Water pressure reg,drip adaptor then the drip line out.I will have to ignore the freezeless silcock and render it useless,no hard freeze there anyway.
And there are no meters every line is run from a main line from the well and the fire hydrents are hooked into a BIG line that runs from a 50,000 gallon holding tank way above
the park up on the hill.The owners don't pay for the water,everyboby gets it free from the well.

[Wet_Boots]

Galvanized is a bit cheesy. For drip, you might do something like I pictured, but with a 1/2" brass tee. Not having the drip line buried works against you, since you won't have any buried pipe to anchor your plumbing in place. Elevation permitting, I would be using a 3/4" antisyphon valve with a battery operated solenoid, like Rainbird's Easy-Rain, or Nelson's Solo-Rain. Pictured is Rainbird's AS valve with drip components downstream. With careful selection of pipe and nipple lengths, you could probably strap the oulet piping to the sillcock, and get extra stability. If the battery-operated valve you've been using works in all positions, you could install it with the flow upwards, and top it with a ordinary atmospheric vacuum breaker.
<img src="http://www.rainbird.com/images/products/drip/control/XACZ-075_sm.jpg">

[drmiller100]

fwiw, i am just finishing up irrigating a mobile home park. 3 inch main lines, constantly pressurized just for irrigation. Not potable water.
then put valves scattered around the park. then we used mp rotors.
Much simpler and cheaper and more reliable then dinking around with hosebibs.
YMMV.

[sheshovel]

I don't think you understand drmiller100 these systems are for individual gardens and plantings front sided and back not large communal areas.Wetboots I have been installing DIG 's in areas too.I just wanted to know about the backflow sillcock thing cuz somebody told me that was all that was needed for backflow prevention and I knew better.I will use all you guy's suggestions and or combination thereof and see how the homeowners are going to react to what it looks like.It's like they don't want to see a valve and all that stuff hanging off the side of the house yet God forbid if you suggest they pick up a hose and water by hand once or twice a week,I mean it's not that much stuff to keep watered.

[Wet_Boots]

Hey, it's California, and if someone objects to the sight of backflow protection, ask them where they moved in from. The Golden State is lousy with visible backflow prevention. They got it and they flaunt it. Against a non-code install without backflow protection, you can't compete in the looks department. Of course, with lines crossing driveways, do looks really matter? Too bad the pipe and drip stuff can't be buried.

[Dirty Water]

Sheshovel, I'm going to go take a few pictures of the last hosebib take off I did for you tommorow.

[sheshovel]

Well Jon where's my pics??

[Dirty Water]

Well Jon where's my pics??


Sorry, I keep forgetting to throw my digicam into the truck.