My wife and I just bought our first house. Its new construction and came with landscaping and irrigation in the front yard. We recently had irrigation installed for the back yard. This is where the problem starts.

There are now a total of 4 zones. 1 and 2 are in the front and 3 and 4 (the new ones) are for the back. When zones 3 or 4 COME ON there is a really loud bang of pipes that's gotten slightly louder over the last 2 weeks. There is no sound when zones 1 and 2 come on. And there is no sound when anything turns off.

The irrigation company thinks its water hammer, but it sounds like that only happens when the water shuts off. At this point, if we can't figure out the cause, my only solution may be to open the wall and figure out a way to keep the pipes from moving so much. Not really what I want to do.

Any suggestions would be appreciated.

Hi Ryan,

I need more details before I can answer. Is the sprinkler system, (1) hooked uo to the house system? (2) hooked up to city water but separate from the house system or (3) on a pump?
Let me know. Regards, Tom

Hi Ryan,

I need more details before I can answer. Is the sprinkler system, (1) hooked uo to the house system? (2) hooked up to city water but separate from the house system or (3) on a pump?
Let me know. regards, Tom

Hmm. Not sure what you mean by being on the house system. We're on city water. But I think its all part of the same system with the house. There is a back flow device with shut off valves between the backflow and the house and the back flow and the street. Does that make any sense?

Does the sprinkler system have it's own meter (2)?

Does the sprinkler system have it's own meter (2)?
Nope. Just one meter.

Then you're tied directly into the house system. About the only thing I can suggest without being there would be to install a air chamber,(see image) on the line that supplies zones 3 and 4. the air chamber would absorb the shock before it got into your house system. Hey! It's better then tearing up walls looking for a banging pipe. Good luck, Tom

Sounds like a good place to start anyway. Thanks.

I am having the same problem with my sprinkler system, however, the hammering occurs when any zone comes on, and water pours out of the backflow valve. The irrigation company has replaced and raised the backflow valve, and had plumbers tack down the pipe that feeds the system. Still have water hammer...

The system is on the house water supply. Would the above solution work for my problem? Is it a do-it-yourself install for someone with little plumbing experience?

Thanks,
Matt

I am having the exact same problem with my sprinkler system, however, the hammering occurs when any zone comes on, and water pours out of the backflow valve. The irrigation company has replaced and raised the backflow valve, and had plumbers tack down the pipe that feeds the sytem. Still have water hammer...

The system is on the house water supply. Would the above solution work for my problem? Is it a do-it-yourself install for someone with little plumbing experience?

Thanks,
Matt

Hi Matt,

The same advice applies to you as to Ryan with the exception that I would cut in a tee and air chamber in the line that supplies the sprinkler system. That way all zones would be covered. You know you can build your own air chamber out of 3/4" PVC pipe and a PVC hard cap. Good luck, Tom

I am having the exact same problem with my sprinkler system, however, the hammering occurs when any zone comes on, and water pours out of the backflow valve. The irrigation company has replaced and raised the backflow valve, and had plumbers tack down the pipe that feeds the sytem. Still have water hammer...

The system is on the house water supply. Would the above solution work for my problem? Is it a do-it-yourself install for someone with little plumbing experience?

Thanks,
Matt

For what its worth, we ended up finding a different solution. We replaced the new Rainbird valves on zones 3 and 4 with Iritrol (sp?) valves. That's what the original system is using. Not sure why, but its completely silent now. We didn't have any issues with our backflow though.