Sprinkler Wiring Done RightApril 24, 2014
A few years ago, I noticed some of my valves weren’t turning on. All these valves were in one sprinkler box and I could soon tell the problem was with the wiring. The wire for this particular valve box started at the valves, snaked its way through a rock retaining wall and under a deck (filled with creep-crawlies) and then under a rock walkway before being buried in a few inches of dirt and entering the garage where it was joined with timer. Needless to say, repairing it wasn’t a pleasant experience and I discovered the perils of a contractor who cuts corners.
Sprinkler wire is a vital part of an underground system. If it breaks, the system won’t work, negating all the benefits of having it in the first place. And because timers and valves are often separated by some distance, it can be a bit pain to repair. I asked some pro installers to share a few tips on how to easily install sprinkler wire and futureproofing against damage and repairs.
The one tip that stood out above all others was to bury the wire inside conduit. The time and costs of installing conduit are nearly identical to doing it without, but the benefits really pay off if you ever need to make repairs. Conduit is pipe meant for electrical wires and cables. It’s usually cheaper than sprinkler pipe because it doesn’t need to withstand internal water pressure. The fittings are often larger and curved so that you can feed a cable through the pipe without running into a hard stop like a tee junction. The pipe is durable, UV resistant and completely waterproof when installed correctly. Like sprinkler pipes, you should bury the conduit at least 6 inches deep (sometimes more if municipal code requires). This will protect it from shovels and tillers.
Conduit is not just for underground, though, and should also be used as you feed wires above ground. Because UV rays can damage the plastic shielding and decrease the lifespan of exposed wires, the conduit will keep from growing brittle and breaking. Plus, it just looks neater and cleaner.
On the topic of conduit, when possible bury it in you’re already sprinkler trenches, thereby saving yourself time and energy digging other trenches.
If you have multiple strands of wire for various sprinkler boxes, it’s okay to feed them through the same conduit because the voltage isn’t high enough to cause interference. Pull yourself an extra few feet of wire so you’ll have spare in the event of repairs.
When wiring the valves, use wire nuts and grease caps. The wire nuts create a secure connection between wires and the grease caps will ensure a waterproof seal. Water getting into the wiring often damages the solenoids beyond repair, so this small investment will prevent extra expense and hassle.
Wiring can be pain free if the proper steps are taken in planning. Follow these tips and you’ll have no problems at all.