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Ken Garlock
08-05-2003, 12:13 PM
Our plumber was required to install anti-siphon outdoor hose connections, what I call sill cocks. They are a grand and glorious PIA :mad: It seems to me that the hazard of back-flow into the house plumbing is somewhere between zero and none!

The problem I have is that when LOML waters an individual plant/tree, she turn on the hose nozzle a little to get a small spray at the base of the tree. If she leaves the water pressure on full, we get a singing of the check valve in the sill cock which is transmitted throughout the house. If she opens the nozzle all the way and regulates the flow at the sill cock, the check valve doesn't work and dribbles water at a noticeable rate. I have talked to my plumber, and he has no answer.

The check valve assembly is permanently attached to the sill cock. The assembly does come apart for maintenance. I have looked at it, but there doesn't seem to be a way to defeat the check valve without having water squirting out around the valve.

The desk wedge who required this setup should be tied to an ant hill :mad:
(Wedge: the simplest tool known to man.)

My question to this fine group is: Does anyone know of a way to defeat this check valve? Is there an insert or repair piece which can defeat the check valve? Any ideas at all are welcome with the exception of trying to justify this device conceived in the underworld.

Don Farr
08-05-2003, 1:35 PM
Ken, you said that very well. I took them all off of my outside faucets. They just unscrewed. I too could never figure out how you could get back-flow into a pressurized pipe.

Lee Schierer
08-05-2003, 1:52 PM
You're right, nothing can flow in against the pressure, but....The problem occurs if there is ever a loss of water pressure. There have been instances of all sorts of chemicals and such being sucked back into water systems when the power fails or a there is a loss of pressure.

If you are on a municipal water system, they are probably required by law. On a single well system, they might be too, depending upon the local area. Sounds to me like you need a water shock arrestor just up stream from the back flow preventer. It is a bellows device that gets rid of the water hammer (singing) when automatic valves close and prevents damage to the rest of the system. It is teed off right near the automatic valve get one with the internal bellows as they work better than the plain trapped air type.

Ken Garlock
08-05-2003, 4:43 PM
Ken, you said that very well. I took them all off of my outside faucets. They just unscrewed. I too could never figure out how you could get back-flow into a pressurized pipe.

Mine looks like it screws on, but I tried a Stilton on it but didn't really lay into it for fear of busting the entire faucet. Maybe I need to put some liquid wrench on it and try again.

Lee: I am sure your are correct in that they are required by local codes. I would rather they put a check valve at the water meter and cover all options. Lawn sprinklers require a triple check valve where they connect to the water line, at least when I had one installed in Plano. I know what a real water hammer is, I had them back in Ohio on a house we had built.(We had a well.) This is a singing sound that I think is the check valve vibrating, not knowing to shut or open due to the low flow rate, but high pressure.

I stopped at a plumbing supply store and talked to one of the salesmen. He exactly what the problem was, but could only recommend some heavy duty water proof grease on the valve itself. I guess the added mass of the grease stops the vibrating. I think the grease would wash out with time....

I may be time to "punch out its lights," and get out the epoxy to seal the relief holes.

Thanks for the comments and ideas.

David LaRue
08-05-2003, 5:33 PM
I know this is not the direction you want to go but, they do make a commercial version for underground sprinkler systems made from brass. I installed one on my well system, and I never had a problem with it. They go for about $80, and they do protect your well form siphoning in chemicals. If your well gets contaminated, you probably have to drill a new one -- not fun and costly. As far as city water is concerned... I'm still trying to figure out the benefit ...
:)

Kevin Gerstenecker
08-05-2003, 6:34 PM
Ken, some of these anti spihon devices that are added to the sill cock have a small set screw to keep them from unthreading when you disconnect a hose. Take a good look around the unit, there may be a small hole that contains a small allen head screw. I agree, these are a pain the the rear, and unless you are using an injection type fertilizer unit, or a hose end sprayer for chemicals, there is no need to worry about getting something hazardous in your potable water system. Trust me, these can be removed............look for a set screw, or if there appears to be none, just back up the faucet assembly with another wrench and remove the device. It sometimes helps to have another set of hands when doing this. If there is a set screw and you miss it, and force the unit off, it will bugger up the threads on the faucet, which is no picnic either. Good Luck, and let us know what you find.

Ken Garlock
08-05-2003, 6:43 PM
Like they say, I have some good news and some bad news :)

Good News is that I leaned on my 10" stilson and got the valve off the sillcock.

Bad News is that the threads on the sillcock are a much finer pitch then what you find on a hose.

While it was off, i played with the spring which keeps the valve in place. I removed it and it seemed to work OK at high pressure, but leaked like a sieve at low pressure. I guess it is off to the borg for some epoxy filler to close the holes. :(

There is always somebody who thinks you are too dumb to take care of yourself. :mad:

Jim Becker
08-05-2003, 6:54 PM
I thought that the check valves were only required for situations where you have an underground pipe, not for faucets directly on the house...but codes are like that, especially local ones.

Don Farr
08-06-2003, 9:10 AM
But if I have a sealed up water system, which I do. If it wasn't there would be a water leak, right? A pipe runs from my well to my house for the water supply. Now lets assume the power fails and stays off long enough for all the pressure in my system to go to 0 psi. Where is the chemicals, etc. going to be introduced into my water supply?
And yes they are required by law in my county on wells and municipal water supplies.
I guess the anti back-up valve police will just have to come get me. If they can get past my gate and dog. :D

Don Farr
08-06-2003, 9:24 AM
Kevin was correct (as usual ) about the set screws. I remember having to loosen them first.

Lee Schierer
08-06-2003, 10:21 AM
Where is the chemicals, etc. going to be introduced into my water supply?


Unfortunately, not everyone is as careful as you might be with regard to chemicals and your water supply, you would be really angry if one of your neighbors sucked lawn chemicals into your aquafer and you or yours got sick. Laws aren't to prevent the good folks from enjoying life, they are there to prevent the dumb ones from doing the rest of us in.

Don Farr
08-06-2003, 10:46 AM
I didn't mean to come off like a smart a-- or anything. My goverment trying to protect me is one of the things that just gets my goat.
I'm going to stop here or I'll be climbing up on my soapbox.

Phil Phelps
08-06-2003, 11:52 AM
I agree with the Guv part, Don. I was havin' a discussion in the chat room with Lee. He said there was a guy in his area that caused a toxic situation because he didn't have an antisiphon valve on his well. I can understand why you should have one on a well and a sprinkler system. Lee also pointed out if you have a garden hose in your soap bucket and the pressure drops, the suds can siphon back into your line. The water department knew this decades ago. Are they going to make law that retro acts installing them on older homes? They did with sprinkler systems in the Dallas area. I believe it is next year that will require all systems, previous and new, have an auto rain shut off valve. So, if it starts raining while your sprinkler is on, it will shut down automatically. I put in my own sprinkler and will either do it myself or have to hire this done. ( sounds like a few sprinkler boyz bought a congressman) That's going to save billions of gallons of water for us here in the Metroplex. (I can lift a Sherman tank over my head, too.) You all should check and see how much it rains from June to October here in North Texas. I'm for the safety of us, in general. But I also think "they" have taken this to a level beyond reason, sometimes. You can get stats on how many people air bags save each year. You won't get stats on how many people die from air bags. Especially children. I think a lot of this has gone way past safety. But what you gonna do?

samson smith
10-01-2011, 2:01 AM
Our plumber was required to install anti-siphon outdoor hose connections, what I call sill cocks. They are a grand and glorious PIA :mad: It seems to me that the hazard of back-flow into the house plumbing is somewhere between zero and none!

The problem I have is that when LOML waters an individual plant/tree, she turn on the hose nozzle a little to get a small spray at the base of the tree. If she leaves the water pressure on full, we get a singing of the check valve in the sill cock which is transmitted throughout the house. If she opens the nozzle all the way and regulates the flow at the sill cock, the check valve doesn't work and dribbles water at a noticeable rate. I have talked to my plumber, and he has no answer.

The check valve assembly is permanently attached to the sill cock. The assembly does come apart for maintenance. I have looked at it, but there doesn't seem to be a way to defeat the check valve without having water squirting out around the valve.

The desk wedge who required this setup should be tied to an ant hill :mad:
(Wedge: the simplest tool known to man.)

My question to this fine group is: Does anyone know of a way to defeat this check valve? Is there an insert or repair piece which can defeat the check valve? Any ideas at all are welcome with the exception of trying to justify this device conceived in the underworld.

The sprinkler pipes, the sprinkler control valve, the sprinkler control timing system are the most important components of any water sprinkler system. Sprinkler control valve plays an important role in any water system. It is used to control the flow of water. It is durable and more flexible.

Jim Koepke
10-01-2011, 2:21 PM
We seldom think about how these things work. If a hose is laying in a puddle and the valve is off, it stops emitting water. Most water valves work great in one direction, not so great in another direction. If another valve is turned on down stream, it can cause a pressure drop at the closed valve and draw "outside" water into the "closed" system.

People tend to feel, "this won't happen here" about such things.

One interesting note, it was just such a situation of an unused air hose left in water that siphoned water in to the air system at Three Mile Island and caused a nuclear accident, according to a source I read. When ever air was used down line, it lowered the pressure in the hose and drew water in. When the water finally got into the air line it messed up some of the control valves that were actuated with air pressure. Their control system air and maintenance air systems were tied together. They shouldn't have been.

They didn't think such a thing was going to happen there either.

So, as crazy as such regulations seem, there is a reason for them.

As far as the plumber that didn't know enough to replace the noisy device, that was either sheer laziness or ignorance.

I have had "singing" check valves. Replacing them has fixed the problem.

There is a lot more information on the web. One good place to start:

http://en.wikipedia.org/wiki/Siphon

jtk

Dan Hintz
10-01-2011, 9:07 PM
You brought up an 8 year old thread to mention this? Are you extremely bored?