irrigation system woes.

[KTM Dad]

Good morning!
ok, here's the skinny, the sysem has it's good points and its bad points, so no YELLIN! first, I put it in MY way, so I didn't need a permit. I hook it up during the season right at the outside faucet, and use a brass "Y" for the hose. now for the problem........
ever sice the new frost free faucet came into the picture, I have been blowing this anti siphon valves right out of them! The irrigation system has a electris sol, 1/2 lines, and TWO water pressure dampers in the main trunk. but still, i blow out the seal on the sillcock. At one point, i had a good pipe bang with it, and that's why I put the pressure dampers in.
What can I do to stop blowing out the seals? At this point, I am about the build a manifold, and run two different sillcocks.

Later........... I'm buzy

[LazyPup]

Before we examine your problem I would like to clarify a point about permits. In your post you stated you did the job yourself, therefore you didnt require a permit and you could put it in your way. That is incorrect.

Regardless of what task we are doing in our homes, if the local governing authority requires a permit for the work we are required to pull the permit and undergo any required follow up inspections. With some exception, most jurisdictions will allow a homeowner to pull a "self help" permit, but when doing so the homeowner must know that you are required to meet the same levels of code compliance as would be required of a licensed contractor.

This is a very important point to remember because often some of the fly by nite, unlicensed contractors will offer to do a job for a price that is substantially lower than the going rate. In instances when permits are required they often convince the homeowner to pull a "self help" permit. Any time someone offers to contract a service and asks you to pull the permit that should raise a red flag. There is a reason why the prospective contractor doesnt want to pull the permit. Usually it is because they cant pull permits because they dont have the proper licensing, insurance or they may even be banned from workning in your jurisdiction for past job performance problems.

Keep in mind that the person who pulls the permit is the one who is ultimately responsible for code compliance, so if you as the homeowner pull a permit, then hire someone else to perform the task, if they do it wrong it is you, the homeowner who is legally responsible for any and all fines or rework costs and you have no legal recourse to recover your loss from the people who actually did the work.

Quite often homeowners take the position that they can do the job themselves and the chance of getting caught doing it without a permit is slim to none. That may be true, BUT, if you do get caught usually the fine is 2 or 3 times the permit fee plus you will still need to pull a permit before you can complete the job. In addition, if you happen to need a permit inspection for another job at a later date and the inspector discovers something that required inspection was done without a permit, the inspector has the authority to immediately rescind your "Certificate of Occupancy" and order you to vacate the structure until such time as the entire structure has been inspected and brought up to currrent code compliance. In my community if the inspector rescinds the "Certificate of Occupancy" the homeowner has a maximum of 180 days to meet full code compliance or the structure must be torn down.

Having said all that, let us now get down to your problem.

You stated in the post that the primary control for the irrigation system is a solenoid valve. I am guessing that the solenoid valve is a 1/2" line solenoid.

Solenoid valves are classified as "quick acting valves". The code now requires that we install a water hammer arrestor in the close proximity of all quick acting valves.

You stated that you had installed "pressure compensators". By that I am assuming you mean that you installed the small 6" high bladder type water hammer arrestors. While they do have the capacity to handle water hammer which is generated by small diameter valves such as those used on dishwashers, ice makers and washing machines, they do not have the capacity to handle the amount of water hammer which is generated by a 1/2" diameter valve.

I personally am not a big fan of frostproof silcocks for a number of reasons, one of which is that they will not tolerate heavy water hammer, which you have learned. My second reservation with frostprrof silcocks is explained in their name, "Frostproof" It is true that they won't freeze and break in regions that experience the occassional frost, but they are not "Freeze proof". In northern climates where the winter temps drop to sub freezing and remain their for extended periods of time the frostproof silcocks do freeze and break at nearly the same rate as a conventional silcock. For that reasong, in cold climates the code requires a "stop & waste" cock be installed on the line at least 3' inside the structure. In winter the "stop & Waste" cock should be closed and the silcock left open to insure no water is trapped in the valve which could freeze and break the valve.

The solution to your problem would be to plumb the irrigation system direct, with a line stop inside the house. The code also requires that you install a vacuum breaker on the line and the vacuum breaker must be positioned at a point that is at least 6" higher than the highest irrigation head. When connecting the line direct you should then install a field manufactured "Water hammer arrestor" that has a sufficient capacity to dampen the effect of a full line stop solenoid.

To make the water hammer arrestor simply Tee a stub of pipe vertical about 18" to 24" and put a cap on the top of that stub. As the lines fill air will be trapped in the vertical stub and it will serve as the water hammer arrestor.