View Full Version : Is this a Backflow preventer?


index
03-31-2011, 03:45 PM
I have a garden hose connection that I use in my garage to wash my car.
Every time I shut off the water that goes to the garden hose, some type of device spouts out water into my garage. This device is prior to my water valve.
Is this the backflow preventer?
Do all of them pour water out when you shut off the water hose? Anyway to prevent water spilling into my garage?

Tscott
03-31-2011, 03:49 PM
Something like this?

http://www.cashacme.com/prod_backflow_v3.php

ptschram
03-31-2011, 03:51 PM
There may also be a much larger device labeled Febco as Febco is a huge manufacturer of reduced pressure backflow preventer valves.

index
03-31-2011, 04:01 PM
Something like this?

http://www.cashacme.com/prod_backflow_v3.php

yeah, that's exactly what it looks like. Can you stop these from pouring water all over the ground when i shut off the water?

mrb
03-31-2011, 04:04 PM
nope. I didnt want these on my hose faucets (they reduce flow as well) so i have a febco PVB with all my sprinkler valves and hose faucets plumbed to the output side of it.

index
03-31-2011, 04:28 PM
nope. I didnt want these on my hose faucets (they reduce flow as well) so i have a febco PVB with all my sprinkler valves and hose faucets plumbed to the output side of it.

so you used something like this?
http://www.febcoonline.com/Products/765

akdiesel
03-31-2011, 04:45 PM
I always used those vacuum breakers to remove gas/air from the lines to reduce water hammer and to aid in fluid packing lines and not so much for preventing harmful gas back flow.
Are these also used to prevent back pressure (liquid or gas) from going to the utility side?

drmarkr
03-31-2011, 05:03 PM
Hate 'em. I remove them if I can get the set screw/bolt out. If it's a bib I use frequently, and I can't get it off, I just replace the entire friggin bib.

Maizen
03-31-2011, 05:23 PM
yeah, that's exactly what it looks like. Can you stop these from pouring water all over the ground when i shut off the water?

Try removing your nozzle first, to alow the water to free-flow from the hose then slowly turn the valve off.

ptschram
03-31-2011, 05:37 PM
Are these also used to prevent back pressure (liquid or gas) from going to the utility side?

It's code almost everywhere to avoid cross-connections, ie. if the pressure should go down, there is a risk that water will be sucked back into the line thus contaminating the public water supply.

I took a class and became certified to inspect them years ago when I ran a private water/sewer utility.

index
03-31-2011, 05:43 PM
It's code almost everywhere to avoid cross-connections, ie. if the pressure should go down, there is a risk that water will be sucked back into the line thus contaminating the public water supply.

I took a class and became certified to inspect them years ago when I ran a private water/sewer utility.

I can see how pollution would be an issue for a sprinkler-type system, but surely for a garden hose it wouldn't be, right? Especially since the hose will never be used to fill up large bodies of water (i.e. submersed in a pond or pool).

holdover
03-31-2011, 06:04 PM
I believe it was in Roanoke VA a few years back, someone was mixing pesticide in a sprayer, somehow the municiple system shut down think it was a broken pipe, homeowner left hose in bucket, system suctioned water out of sprayer into the system. I want to say this was 20+ years ago that I read it in the local paper, the roanoke times. I believe this was just before they became a requirement. Created quite a stirr

REAL HOT SCHITT
03-31-2011, 06:44 PM
i have a garden hose connection that i use in my garage to wash my car.
Every time i shut off the water that goes to the garden hose, some type of device spouts out water into my garage. This device is prior to my water valve.
Is this the backflow preventer?
Do all of them pour water out when you shut off the water hose? Anyway to prevent water spilling into my garage?

i wonder if u had this back to front?

6768rogues
03-31-2011, 06:56 PM
This is a backflow preventer, otherwise know as an RPZ: http://www.watts.com/pages/whatsnew/919.asp If you have one of these and it constantly lets water out, it might need to be rebuilt. They also need to be tested annually. Here they are only required for commercial water users, residential is exempt.
There are also double check assemblies known as backflow preventers.
There is also a simple vacuum breaker. It is supposed to keep your hose water from being siphoned back into the potable water system. Code requires them here. It lets air in when a hose is shut off. It will not work if the hose is higher than the vacuum breaker. If it is leaking, it is faulty, it should let air in without letting water out.

mrb
03-31-2011, 07:11 PM
so you used something like this?
http://www.febcoonline.com/Products/765

yep. and its outside the house of course. my line from the street splits in two, i have a ball valve on each outlet of the T, one supplies a pressure reg then the house, the other supplies a second pressure reg, then the PVB, then my sprinklers (with valves in UG vaults) and hose bibs. I also have a 3/4in ball valve with a GHT fitting on it incase i want more water than comes out of a hose bib :D

the inspector thought it all was pretty ridiculous, but i can flush a toilet with the sprinklers running and not notice a change in pressure in the shower which was a huge problem before my upgrade.

mrb
03-31-2011, 07:14 PM
This is a backflow preventer, otherwise know as an RPZ: http://www.watts.com/pages/whatsnew/919.asp If you have one of these and it constantly lets water out, it might need to be rebuilt. They also need to be tested annually. Here they are only required for commercial water users, residential is exempt.
There are also double check assemblies known as backflow preventers.
There is also a simple vacuum breaker. It is supposed to keep your hose water from being siphoned back into the potable water system. Code requires them here. It lets air in when a hose is shut off. It will not work if the hose is higher than the vacuum breaker. If it is leaking, it is faulty, it should let air in without letting water out.


those backflow preventers are only required on commercial in most places, the vaccum breakers on the hose bibs are required everywhere now and have been for some time. they usually burp water if you have a charged hose connected to it with nozzle shut off, and you turn the hose bib off as there is more volume and pressure in the hose than the upstream side of the vaccum breaker so its doing its job.

turn it off while holding hose nozzle open and it wont burp water.

Frank The Plumber
03-31-2011, 07:35 PM
I'm surprised that some of the guys whom I consider to be very intelligent and give excellent advice on very stringent applications would be so unconcerned about removing one of these devices. This is a vacuum breaker, it prevents back siphonage of waters into your domestic water supply. It is a point of use device.

The other unit the Watts Reverse Pressure Zone valve is an isolation device. It prevents waters from being pulled from a home into the municipal water supply. It requires a yearly test to certify it's safe operating condition. If it fails testing the homes water supply may be terminated until it is restored to proper function.

These devices protect you from poisoning, When they are maintained unilaterally by all homes they protect all of us from each other or all of us from the ignorant and negligent.

There have been numerous cases in which acids fertilizers, very caustic chemicals have been drawn into the municipal drinking water of various communities with horrific results.
I am a certified backflow inspector, I repair test and install devices such as these to protect you from each other as well as the possible contamination of your drinking waters. This is not a large part of my work but I respect it as it is a product consumed by the innocent and the trusting, therefore I am a Zealot when it comes to pure clean water, you and your children all deserve to have a clean safe reliable water source, It is my sworn duty to protect you and yours from this danger. No one should ever be poisoned by drinking water in their own home.

Removing these devices is equally if not more dangerous than removing the grounds from all of your tools and home electrical system.

When a hose is turned on that has one of these devices it will spit until the diaphragm seats. If it spits longer it may need service. Please service them rather than remove them, they are a safety device, trust me they are necessary.

I once yearly must go for a course and we are commonly shown some of the circumstances of altering and or operating our water systems without these types of devices. We are often shown photos of chemical burn victims that simply went to take a shower and turned on the faucet to recieve a chemical bath that removed large parts of skin and flesh.

I realize that they are an inconvenience, as is a seat belt or a bicycle helmet, or safety glasses and I am sorry for that, but I urge you to develop an understanding of why they are there and maintain restore or replace them as you find them unfit.

akdiesel
03-31-2011, 08:09 PM
Thank you for the information on these items.
I have my own well and have not seen these items on my system or any of the houses I used to own that were on city water except maybe a basic check valve.

index
03-31-2011, 08:22 PM
turn it off while holding hose nozzle open and it wont burp water.

Ahh, if it's as simple as that, then i don't have a problem leaving the RPZ on there as long as it doesn't create a big puddle in my garage every time i turn off the garden hose. I'll test it out tomorrow.

mrb
03-31-2011, 08:24 PM
I'm surprised that some of the guys whom I consider to be very intelligent and give excellent advice on very stringent applications would be so unconcerned about removing one of these devices. This is a vacuum breaker, it prevents back siphonage of waters into your domestic water supply. It is a point of use device.



who said to take them off? My setup, i didnt want the the vaccum breakers on the hose bibs so I used a large pressure vaccum breaker upstream from all my sprinkler valves and hose bibs. Same (or better) protection, quite a bit more expensive, but I like how it works much, much better.

R6 Racer
04-01-2011, 10:28 AM
I took mine off almost right away after my home was finished being built. (the one that was on the spigot inside the garage at least, the one out the back yard doesn't bother me so its still there) It was a major pain in the ass! Mine spit water when I shut the hose off, when I turned the hose on, & it would spurt water while I wound the hose up onto the reel, one spurt with every wind of the reel!

I had never before seen these on any of my homes (I have lived in 3 homes prior & 1 of them was a "new" built). If these are really necessary then why can't someone make one that works without spitting out water all the time?

Also if they are that necessary could I just put them on the far end of the hose so that when the spurting went on it would be outside?

Lastly, my hose is a "out only" affair. I use quick release stops at every connection. The kind that when I pull off the hose nozzle or sprinkler head the water flow is stopped right at that point. I don't use any poisons or acidic chemicals with the hose, I use a portable sprayer for anything like that!

To me this seems like another inatiquit attempt by the regulatory big brother to try & save us from ourselves when common sense would work just fine.

Steve

ptschram
04-01-2011, 10:48 AM
I'm surprised that some of the guys whom I consider to be very intelligent and give excellent advice on very stringent applications would be so unconcerned about removing one of these devices. This is a vacuum breaker, it prevents back siphonage of waters into your domestic water supply. It is a point of use device.



These devices protect you from poisoning,.


As a former certified wastewater treatment operator, drinking water operator, etc. I applaud your comments.

The incidents I have had related to me were all involving bacteria contaminating public water systems with toxins.

The hose that hangs into a sink can suck sewage out of the sink and put it in YOUR drinking water. Think about it, there is a direct conduit from the drain in your sink to the bowl of your toilet.

akdiesel
04-01-2011, 10:51 AM
From what I gather in the story told earlier is that you may not use chemicals but there will be someone who does and they don't want any three eyed people popping up.
Not all rules are make sense but they are usually made due to someone or something creating a problem.

Frank The Plumber
04-01-2011, 02:50 PM
A vacuum breaker is cheap and easy, the spit means its working.

You can be poisoned as easily as this:
Your neighbor decides to shock the holy god out of his pool, he gets it on his shirt and it's leaving white spots. He fills his pool with a garden hose, no vacuum breaker, no RPZ device. His line is wide open to system.

A home 2 blocks away is on fire, the kids in the neighborhood have a hydrant open, a pump truck pulls up from the local fire department, fires up the high pressure pump and starts pulling water from the line, the main, due to the hydrant being open has difficulty providing adequate volume for the pump, the velocity of water in the main racing past the guy with the pool creates a venturi effect. The water passing by the service at a high rate of flow creates a negative pressure zone and pulls water from the neighbors line into the water mains.

Everything after that is an absolute horror story.

By removing the vacuum breaker you are removing your first line of defense against any bacteria, chemical, or back siphonage event that may occur to you.

The RPZ is there to protect everyone else from you.

If you remove the simple visible vacuum breaker and replace it with a non testable device you have no way of knowing if it is working. Even a $120 dual check is not testable, They can and do fail all the time, way better than nothing but still not 100%. That simple little pain in the ass device is 100%. When it spits it closes and that water is spit out, not taken back in.

75% of all people who have an irrigation system have a service applied chemical treatment done 3 times per year. I have people who have told me it's not important and they refuse to test their irrigation system RPZ. It's too expensive. $75 a year. The first person who will get sick will be them.