WJRZA 18/4 Solid Sprinkler System Wire 50ft, 18 Gauge Irrigation Wires PVC Jacket Sprinkler Cable for Underground Irrigation Valves Field Central Control System

Why I reached for this 18/4 sprinkler wire

A recent controller relocation and two new remote valves pushed me to run fresh low-voltage cable across an established lawn—never my favorite task. I wanted something I could bury once and forget. This 18/4 sprinkler wire fit the brief: four solid 18 AWG copper conductors in a tough PVC jacket, rated for direct burial and high temps, with the UV resistance I like for short above-ground hops into valve boxes and controllers. After a couple weeks of trenching, splicing, and testing, here’s how it performed and where it makes sense.

Build and specs that matter in the ground

• Conductors: Four solid copper, 18 AWG. Solid is the right choice for irrigation solenoids; it seats reliably under screw terminals and gel-cap splices.
• Jacket: PVC, listed as waterproof and UV/sun-resistant. It’s stout without being overly rigid.
• Temperature rating: 194°F (90°C), which is generous for direct sun and hot climates.
• Outer diameter: About 6.2 mm, so it fits standard waterproof connectors and valve box fittings without fuss.
• Direct burial: Yes. That’s the non-negotiable box for sprinkler work.

The copper is genuinely copper (not copper-clad aluminum), which shows in both the weight and how cleanly it strips. For low-voltage irrigation, true copper helps minimize voltage drop over longer runs and tends to hold up better in damp, slightly acidic soils.

Installation: trenches, splices, and controller hookups

I used the cable in two ways: as a 50-foot home-run to a pair of remote valves and as a splice-in extension to an existing harness during a controller move. The jacket slit smoothly with a utility knife and the individual conductors stripped best with the 18 AWG notch on a ratcheting stripper—no nicking or broken strands (solid conductors can be unforgiving if you gouge them).

A few practical notes from install day:
- Flexibility: The cable is flexible enough to snake through valve box knockouts and lie flat in a shallow trench. It’s not rubbery, but it also isn’t the stiff, coily kind that fights you at every turn.
- Splicing: Use gel-filled, waterproof connectors (DBY/DBR or equivalent). The jacket keeps water out along the run, but your splices are the weak link. I tug-tested every connection and had zero pullouts or compromised seals.
- Bury depth: I set mine at 6–8 inches below turf, which is typical for low-voltage irrigation. If your jurisdiction has specific depth requirements, follow those. I also dropped a caution tape above the run to save future me from a shovel-induced headache.

One small advantage of the 6.2 mm jacket is that it resists accidental nicks when you backfill with modestly rocky soil. That said, sharp stone edges will beat any PVC jacket over time—sift or line the trench if you can.

Performance and voltage drop in the real world

Sprinkler solenoids are forgiving, but they still need enough voltage to pull in consistently. With 18 AWG, the math looks good for typical distances. Resistance is roughly 6.4 ohms per 1,000 feet. For a 200-foot loop (100 feet out, 100 back) at 0.2 amps, you’re looking at around a quarter-volt drop—basically nothing against a 24 VAC system. Even a 500-foot loop only drops about 1.3 volts at that load.

In practice, each zone fired cleanly from a Hunter-style 24 VAC controller with quick, confident solenoid actuation. No chatter, no sluggish valves, and no intermittent runs when multiple zones cycled back-to-back on a hot afternoon. The jacket didn’t soften or deform where it crossed a stone border with full sun exposure, which speaks well of the temp rating and UV resistance.

Planning conductor counts: what 18/4 really gives you

Four conductors is perfect for a small expansion or a short remote cluster of valves:
- Common wire (shared return) + three zone wires = three controllable valves.
- For two valves, you get one spare conductor for future use or a redundant common.

If you’re planning six or more valves in a single remote box, you’ll either want a higher conductor count from the outset or run a second cable. The 50-foot length is convenient for modest repairs and additions; for new installs or long runs, grabbing a larger spool (and a higher conductor count) is usually more efficient.

Durability over time

Direct-burial cables live a hard life: moisture, soil movement, root pressure, and the occasional shovel strike. The jacket on this cable inspires confidence. It’s thicker than bargain-bin options I’ve used, and the UV resistance should mitigate the cracking you sometimes see on short exposed sections entering a valve box or controller enclosure.

Still, the long-term success of any irrigation wiring comes down to:
- Good splices—gel-filled connectors, properly seated conductors, and no exposed copper.
- Sensible routing—avoid sharing a trench with high-voltage lines, and cross them at 90 degrees when needed.
- Protection at points of strain—use conduit sleeves where you exit grade or pass under hardscape.

If you’re in gopher or mole country, conduit is cheap insurance. The jacket resists moisture, not teeth.

What I liked

• True copper conductors: Better conductivity and corrosion resistance than CCA, and they strip and terminate predictably.
• Jacket balance: Tough enough for burial, flexible enough for tight spaces, and UV-stable for short exposures.
• Installation ease: Clean stripping, minimal coil memory, and solid feel in waterproof splices.
• Sensible rating: 194°F and direct burial provide headroom for hot climates and sun-baked surfaces.

What could be better

• Conductor count options: 18/4 is useful, but many installs benefit from 18/5, 18/7, or higher. If you’re retrofitting, think ahead to future zones.
• Length selection: Fifty feet is a handy service length; having 100–250 foot options would reduce mid-run splicing on bigger properties.
• Cold-weather handling: Like most PVC, it stiffens in real cold. If you’re working below freezing, warm the coil before unspooling to prevent kinks.

None of these are dealbreakers; they’re more about choosing the right cable for the job.

Compatibility and use cases

The cable plays nicely with standard 24 VAC irrigation controllers from the usual suspects. It’s well-suited for:
- Adding a couple of zones to an existing system
- Relocating a controller and extending the valve bundle
- Running a small remote valve cluster for a side yard or garden bed
- Short hops across hardscape where conduit isn’t practical, provided you protect entry points

Beyond irrigation, it can serve other low-voltage signaling needs outdoors, but it’s not shielded and not intended for high-voltage or communication-critical runs. For anything code-sensitive, check local requirements.

Practical tips from the install

• Label both ends before burial. Even four conductors can get mixed up under pressure.
• Leave service loops at valve boxes. Future repairs are easier with spare inches.
• Use a shallow bed of sand or fine soil to cushion the cable before backfilling.
• Keep a photo log of the trench path with landmarks. It’s a gift to your future self.

The bottom line

I’m impressed with this 18/4 sprinkler wire. It’s the combination I look for in irrigation cabling: solid copper for reliable conductivity, a jacket that holds up underground and in the sun, and easy handling during install. It fired valves consistently, spliced cleanly, and felt built for the kind of set-it-and-forget-it reliability you want once the turf is patched and sprinklers are back on schedule.

Recommendation: I recommend it for small to medium irrigation additions, controller relocations, and any run where four conductors and about 50 feet will do. If you need more zones or longer distances, pick a higher-conductor variant or longer spool, but stick with similar materials and ratings. For the jobs it’s designed to cover, this cable is a dependable, no-drama choice.