Drip Irrigation - Tips, Tricks and TroubleshootingBy LariAnn Garner (LariAnn)
February 4, 2009
A Little Help from your . . . friends?
So you've done it and your drip system is fitted together and ready to go. Have you turned on the water source, opened the valve (as per the instructions that came with it) and checked the system for leaks and adequate water distribution at all of the emitters? That's the first order of business, if you have not already done it. Also, whichever type of battery driven valve(s) you chose for your installation, make a note of the date you installed your valve battery so as to provide you a reference when the time to replace it arrives.
What, you say? You haven't installed your system yet? That's not a bad thing because, using the information included in this article, you can make a system even better than merely a "basic" installation would provide. I learned quite a bit as I went along with my system, but then again, I was setting up a multi-zone, multi-manifold system to service many hundreds of plants, two greenhouses and a shadehouse area, all of which are scattered around nearly our entire property. This being said, it made the whole project into an on-the-job training exercise.
Unexpected surprises await you, too, especially if you live in a rural or semi-rural area where wildlife can be found. My place is not so rural, but I found quickly that a small varmint decided that it would be fun to nibble on some of my poly spaghetti tubing. On inspection of one zone, I noticed that the pressure was lower than it should have been. I found the reason when I spotted some water spraying out where it should not have been. Two or three lengths of tubing were chewed partially and had to be replaced. That was some little "help" that I really did not need!
On and off, or stuck on?
My first manifold was my prototype (see part of it in thumbnail picture above). As you can see, the valve inlet is screwed directly onto the manifold piping, and the valve outlet elbow is screwed directly into the valve outlet. This works fine as far as it goes, but if I had to remove the drip line for some reason, I would have to cut the drip line, then unscrew the insert fitting. Then I'd have to go through the trouble of getting that cut piece of pipe off the insert fitting so I could use the fitting again. I'd face a similar problem if I had to remove the valve itself. In my next manifold, I included a union fitting between the manifold piping and the valve, enabling me to unscrew the fitting by hand and remove the valve. The outlet end solution is to use a compression fitting with female hose thread coupling to connect to the drip line. This enables you to unscrew the drip line from the valve just as though you were unscrewing a hose from a faucet, with no pipe cutting involved and no struggle to recover the fitting for reuse. Of course, the outlet of the valve has to have a fitting with 3/4-inch male pipe threads on one end and male hose threads on the other end, because the valve outlet itself is threaded as 3/4-inch female pipe.. These fittings come with the DIG valve, or you can get them separately at your drip irrigation supplier. I found that the electric ball valves from Irrigation Direct are already threaded to hose threads, and in addition, the inlet side is also a union-type of connection, which saves me having to add a union fitting when using those valves.
If you are using a sediment filter instead of a mesh filter, be sure you install it so that you can open it up easily to replace the cartridge. These filter housings are usually mounted onto a wall, post or other solid object, with enough clearance below them to allow the unscrewing of the cartridge housing. You may also choose, as I did, to install union fittings on both the inlet and outlet sides of the filter unit so as to allow you to remove the whole unit easily if necessary. This would be important if the unit is located in a place where you cannot obtain enough clearance to allow you to replace the cartridge easily. You should also install a manual shut-off ball valve on the inlet side so you can shut off the water supply at the filter for maintenance. This also allows you to shut down all the zones serviced by this filter if you need to replace a valve, add a new valve, or do other repairs or upgrades.
Timing is Everything
So you've got your zone set up properly, there are no leaks, and you've opened the valve to verify that all emitters are working properly. Then you wake up and go out to see your newly watered plants, and they are all dry! What happened? Well, one easy mistake is in programming the valves. When setting up my system, I noticed that one of my zones didn't seem to be coming on at all. I checked the time on the valve at 10 in the morning, at the valve read 10:00. I reset the start time to 10:30 and watched to see if the zone would come on at 10:30. It did not! I was perplexed until I discovered that I had the zone set to come on at 10 PM instead of 10 AM. So be sure that you have set the right days you want and the right time of day, including whether it is "AM" or "PM".
Last, but not least, be sure you provide a means to purge your mainlines both after installation and later on, if need be. The easiest way of doing this with linear zones is to put a fitting with a screw cap at the end of the zone. This way, you just unscrew the cap, then turn on the valve to purge the line. You should do this immediately upon installing to remove any dirt or debris that either was already in the pipe, or found its way into the pipe during the installation process. Looped zones are trickier; you should purge them right before making that final connection to form the loop.
Check all your emitters at least once per week to be sure they are functioning properly and not clogged. Of course, you have to do this when the zone is running. Make adjustments if necessary, especially with shrubblers, so that you have just the right amount of water coming out.
My hope is that what I've shared in this group of articles will help you have an easier time of setting up your drip irrigation system. If you have any questions about topics I didn't cover (of which I'm sure there are plenty), feel free to ask! Here's to happy, well-watered plants, water conservation and more free time for you!
Below are links to my other articles on this subject:
Image credit: LariAnn Garner