Backflow preventer in crawlspace??

Discussion in 'Irrigation / Sprinkler Forum' started by crosby1, Sep 23, 2009.

  1. crosby1

    crosby1 New Member

    Messages:
    28
    Location:
    Virginia
    i just had an irrigation system installed @ the house. for now, i opted to tap off the water main under the house and not have a separate meter installed.

    they put the backflow preventer in the crawlspace and i was wondering if this is an acceptable place for it to be?

    there were quite a few problems with the install, so i'm not really keen on bringing this up with him until i have some good info.

    thanks...
  2. FloridaOrange

    FloridaOrange Plumbing Designer

    Messages:
    1,317
    Location:
    SW Florida
    I think it would be acceptable as long as it's accessible for maintenance and testing.
  3. Gary Swart

    Gary Swart In the Trades

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    Location:
    Yakima WA
    Backflow preventers should be certified annually by a licensed and certified inspector because they do not last forever without replacing seals, O rings, and etc.. I know some local authorities ignore the EPA and have no requirements for this, but when the BFP fails, your family and the entire community is at risk. For this reason, your BFP should be in a place convenient for inspection and testing. My city inspects the BFP the first time, then homeowners are required to make arrangements with a qualified inspector each spring. If this is not done, water service to the home is discontinued.
  4. crosby1

    crosby1 New Member

    Messages:
    28
    Location:
    Virginia
    well, it is in a convenient place. it's right inside the door to the crawl space. my question has more to do with what happens if and when water comes out of it?

    i mean, i'm going to have to winterize the system soon and then it will be filled with air. when i turn the water back on in the spring, aren't i going to get gallons of water coming out of the top of the BFP?

    it just seems to me, that it should be outside the house; not in the crawl space underneath...seems like a set-up for disaster.

    maybe i'm way off base and it's OK; just trying to get an idea before i go off on the guy again.

    thanks.
  5. tomm

    tomm New Member

    Messages:
    41
    Crosby1, you are 100% right.

    From your description, I'm assuming you have a pressure vacuum breaker. Please post a picture.

    If so, you have got to get that out of your crawl space! When it dumps you will potentially have a huge mess on your hands. They are to be installed outside.

    I'll bet that its not even installed above the highest head, being that its in a crawl space.
  6. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    I would be surprised with a new install using a pressurized Vacuum breaker. Most places have banned them for use on lawn irrigation. They are moving to have RPZ devices installed. Which requires an air gap and a drain to be installed on it to carry the water away to a safe place to drain off with out causing property damage.

    Notice the pipe at the bottom of the device in the picture that is attached to the air gap which catches the discharge of the RPZ.

    Attached Files:

  7. tomm

    tomm New Member

    Messages:
    41
    PVB's have not been banned in most places for use on lawn irrigation.
    Last edited: Sep 25, 2009
  8. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    Well then I better call all the plumbing inspectors I dealt with in Illinois and inform them of this.
  9. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    Here you go from the Illinois code book itself.

    Section 890.1140 Special Applications and Installations

    d) Lawn Sprinklers. Any lawn sprinkler system connected to a potable water supply shall be equipped with a reduced pressure principle backflow preventer assembly (RPZ). The RPZ may be located outside provided it is protected from freezing or is removed at the end of the season, and it conforms with Section 890.1130(g)(1). ​
  10. tomm

    tomm New Member

    Messages:
    41
    I guess Illinois is different, but in the majority of the country a PVB is perfectly
    acceptable as a backflow device for a residential sprinkler system.
  11. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    Illinois used to allow PVB, but as required RPZ for a few years now. Other states and municipals are doing so as well. PVB are not good enough to prevent the nastiness that grows around them sprinkler heads from back flowing into the potable water system.
  12. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,247
    Location:
    Cave Creek, Arizona
    Pvb

    IT is a local issue, but a pressure backflow preventer is supposed to be installed so it is ABOVE, and usually one foot above, the highest irrigation head, so a crawl space installation would not be proper, AND it is supposed to be in a location where discharges will not cause damage, which could also preclude it being in a crawl space.
  13. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    Wow, IL must have a strong backflow testers' union, to get that law in for residential!

    Here, backflow is almost universally done using anti-siphon valves, in residential.
  14. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    The union has nothing to do with Illinois plumbing code. Let me refer you to a post on PZ http://www.plumbingzone.com/f2/yup-i-went-there-5015/
  15. johnjh2o1

    johnjh2o1 Plumbing Contractor for 49 years

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    Location:
    South*East
    That's a big jump from a PVB to a RPZ. Why not a DBL check it has no discharge to contend with and offers more protection for back flow.

    John
  16. SewerRatz

    SewerRatz Illinois Licensed Plumber

    Messages:
    1,705
    Location:
    Chicago, IL
    You would have to ask the code officials about that. But I suspect it has to do with the degree of the hazard of what can backflow from a lawn sprinkler system. The water that pools around the sprinkler heads can have insects, pesticides, herbicides, fungicides, fertilizer, worms, and other contaminants. Which would make it a high hazard backflow issue which according to the EPA codes would require an air gap (which in this case wont work) or a RPZ valve installed.

    There has been many cases where people have gotten ill from drinking water that has gotten contaminated by the lawn sprinkler systems. I was told about one where a local high school football team gotten sick from drinking water that was contaminated with animal waste.
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