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Antisyphon Valves

Discussion in 'Irrigation' started by Wet_Boots, Mar 4, 2007.

  1. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,592

    With the rising cost of brass backflow preventers, is anyone looking at using antisyphon valves instead? Less expense. No valve boxes to dig. No critter-chewed wires. Easy winterizing.

    Customers asking "What the &%@#*$!!" are these?!" probably remain the biggest hurdle.

    The only real downside to AS valves I've seen are visual, if foundation soil settling twists an installation, and the inevitable need to replace the vacuum-breaker poppet washer somewhere down the line. Also, depending on brand (like Irritrol) the solenoids' ability to endure weathering might be questioned.
  2. londonrain

    londonrain LawnSite Silver Member
    Messages: 2,129

    The water systems in my area require a DCVA regardless. They are also on the lookout for unprotected systems without DCVA's. We installed two DCVA's last week, one was on a meter converted to an irrigation meter. The other DCVA was on an unprotected system with just a gate valve.
  3. sildoc

    sildoc LawnSite Silver Member
    Messages: 2,925

    Never even considered asv's. other than the ease of repair I cant stand the things. No matter how you obscure them in a landscape they always stick out like a sore thumb. Most people are so used to not seeing asv's that when they do it is a homeowner install.
  4. bumper

    bumper LawnSite Member
    from So. Cal
    Messages: 187

    The vast majority of residential installs in our region are AS valves, not difficult to hide with proper placement and the correct plant material.

    I can only remember a faint few service calls where ASV's were not used.
  5. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,592

    Any regional code (like the SBCC) allows lawn sprinklers to be protected by antisyphon valves, which are toxic-rated. Local ordinances might require DCVA's, like many towns in my area did, before the code rewrites made 'toxic-rated' a must. Interesting times, for awhile, when ordinances and codes were contradicting each other. Prevailing codes in my region would allow a locality to raise the bar, and require a PVB or RPZ (both toxic-rated) but they could never mandate a DCVA (not toxic-rated)

    Unless I see actual documentation, I will always believe "You must use a DCVA, and not a PVB or RPZ or antisyphon valve" to be a result of local ordinance or (perhaps even more likely) one of those "Because I'm the inspector, and I say so" ~ The logic in using a lower-quality backflow preventer escapes me.
  6. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,592

    This probably isn't a question for users of Double Check Valve Assemblies. Awful hard to trade in buried backflow for anything above ground. More of a PVB versus antisyphon valve comparison.
  7. sildoc

    sildoc LawnSite Silver Member
    Messages: 2,925

    Our community is kind of screwed up. I see alot of pvb's around on the supper old 20+ year systems, You know the ones that used brass sprays and such. but now you are required to use Double checks if you are licensed only and if you are homeowner you can just use asv's with no double check. ??? only those old ones are grandfathered in. Crazy.
  8. PurpHaze

    PurpHaze LawnSite Fanatic
    Messages: 5,496

    I have ASVs on my house system. I originally put them in 25 years ago and just went manual to start with. Then I converted to automatic about 18 years ago and just kept the ASVs instead of renovating the whole thing. I'm still trying to figure out if I was a DIYer back then. The system still has the original valves and MAs but they don't leak because maybe I was in professional install mode even way back then. :)
  9. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Messages: 50,592

    This is the 'because I said so' aspect I mentioned before. A genuine code requirement for DCVAs would govern all installations. Codes don't care who does the work.

    None of the old stuff around here was grandfathered, so all the existing DCVAs became non-compliant the moment the new code was adopted. Sympathy from the government was sadly lacking.
  10. sildoc

    sildoc LawnSite Silver Member
    Messages: 2,925

    You probably didn't even realized it was your calling!!!!!:laugh:

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