Sprinkler Diagnostics: The Curse of the No Mod 1

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Just a few days ago, a crippling problem arose on our old Rain Bird ESP Modular sprinkler controller. Since it came with the house, it’s about 16 years old, and while Rain Bird still makes and supports this product, it’s beginning to have issues. This is about the start of the watering season, though it’s nowhere near hot enough to start watering twice a week, and the city has yet to issue a watering notice, but we decided on about Wednesday, March 16 that it was time to test the system and make sure everything was ready. Well, it turned out that upon testing Zones 5 and 6, the display on the controller read “No Mod 1” and refused to start. Upon attempting to run Zone 6 (the backyard) later that day, the system worked, though the display flashed “No Mod 1” about every three seconds and the sprinklers went up and down, up and down, intermittently to the pattern of the No Mod 1 message. This signaled a bad module, and since the control module was still working (zones 1, 2, 3, and 4 were working fine), the only one left to blame was module 1. So we promptly ordered a new mod 1 that would arrive the next day.

Now this sprinkler system has another issue: the Irritrol rain sensor that comes with the Rain Bird controller that’s supposed to sense rain & freeze and automatically shut off the system can no longer be found. The sensor isn’t present on the roof, although the receiver in the garage is still there. In the photo above, you can see the little white box to the upper left of the controller–that’s the Irritrol sensor. That’s why the switch for the sensor on the control panel is set to “Bypassed.” So we have to go out and turn the sprinkler system to OFF manually every time rain or freezing conditions arise. That’s another thing that needs to be replaced.

So, after getting the new module in just today, we ran another test on the system. Unfortunately, we were only able to run Zone 6, not Zone 5, because a sprinkler head on Zone 5 is broken (long story, will be discussed later in this post.) Everything worked fine, and there wasn’t any funky intermittent No Mod 1 warnings. Since we were already out at the sprinkler box, we decided to program the system to get it ready for the beginning of the watering season, and while we weren’t able to make sure Zone 5 was all in order, the controller is now all programmed. It was pretty easy, since after we cut the power to the controller via the breaker, it remembered most of the time and date settings.

And now for the busted sprinkler head. On Wednesday, when we decided to run a test on Zone 5, we noticed a huge fountain of water coming up along the side of the house. That was a broken sprinkler head all right, and we promptly got to work on shutting off Zone 5, since the whole area had already gotten flooded. Even today there’s still a large amount of mud over there that was built up. Today when we went out to install the new module, we decided we would try to find exactly where it was and mark it with a flag, which was done successfully. Now the tricky part is ordering the correct sprinkler type: the one that was broken was a 12Q type, meaning it only watered in a quarter circle, which is useless already. So we’ve decided to get an H-type head this time. Unfortunately, since there are so many options for sprinkler heads like the one we need, we can’t decide: there’s a 4-inch one that’s probably too short, there’s a professional-grade 4-inch one, and then there’s another moderate-grade 4-inch one, then there’s an 8-15-inch normal one. In order to really know the exact type we need, we’re going to have to dig it up. But until then, Zone 5 won’t be running.

Overall, the module section of this irrigation system event has been resolved, but there’s still a broken sprinkler head to be replaced, and now it sounds like there’s going to be a post on a broken garage door system. (After turning the power back on after finishing up the module installation, the garage door went berserk. It’s now opening all the way to its physical limits and then ignoring any adjustments being made to it.) We’ll see how we’re going to sort that one out.