Sprinkler Issues? A Sunnyvale Homeowner’s Guide

Maintaining a lush, green lawn in the Bay Area presents a unique challenge. With water conservation being more important than ever, every drop from your sprinkler system counts. An inefficient or broken system doesn’t just waste water and drive up your utility bills; it can also leave you with brown, patchy grass. Spotting problems early is key to keeping your landscape healthy and your water usage in check—a specialty of Mr. Sprinkler Repair, who brings years of experience solving sprinkler system issues for Sunnyvale homeowners.

Many homeowners in Sunnyvale notice tell-tale signs of trouble but aren’t sure what they mean. Is that one dry patch a big deal? Why is one zone not turning on? Mr. Sprinkler Repair in Sunnyvale, your trusted local expert, is here to help you pinpoint the problem. This guide will walk you through the most common sprinkler issues we see, from electrical faults to uneven watering, so you can identify the problem and understand your next steps—or know when it’s time to call in a professional.

Electrical Failures: When Your System Won’t Start

One of the most frustrating sprinkler issues is when nothing happens. You set the timer, but a zone (or the whole system) fails to activate. Often, the culprit is an electrical failure. These issues can range from simple connection problems to more complex component failures.

Key Symptoms:

One or more sprinkler zones fail to turn on.
The entire sprinkler system is unresponsive.
Your circuit breaker trips when the system is scheduled to run.
The controller display is blank or shows an error message.

Common Causes:

Faulty Wiring: Buried sprinkler wires are vulnerable to damage from digging, pests, or simple degradation over time. A cut or frayed wire can interrupt the signal from the controller to the valve.
Corroded Connections: The valve box is a damp environment, making wire nuts and connections susceptible to corrosion. This rust and decay can break the electrical circuit.
Bad Solenoid: Each valve has a solenoid, an electromagnetic coil that opens the valve when it receives power. If a solenoid burns out, the valve it controls will not open.
Controller or Transformer Issues: The controller (timer) is the brain of your system, and its transformer provides the low-voltage power. Failure in either of these components can render your entire system useless.

DIY Checks & When to Call a Pro:
You can start by checking for simple issues. First, ensure your controller is plugged in and the outlet is working. Check your home’s circuit breaker to see if it has been tripped. If the controller display is blank, the issue may be the transformer.

However, diagnosing specific shorts, tracking down buried wire breaks, or testing solenoids with a multimeter requires specialized tools and knowledge. If basic checks don’t solve the problem, or if you’re uncomfortable working with electrical components, it’s time to call a professional. Handling wiring incorrectly can cause further damage to your system.

Non-Rotating Heads: The Source of Dry Doughnuts

Rotor heads are designed to sweep back and forth, distributing water over a large area. When one stops turning, it waters the same small spot over and over, inevitably creating a green patch surrounded by a dry, doughnut-shaped ring of brown grass.

Key Symptoms:

A rotor head gets stuck in one position.
The head pops up but doesn’t spin, watering only one area.
Noticeable dry arcs or circles in the lawn.

Common Causes:

Debris in the Head: The most common cause is dirt, sand, or small pebbles getting lodged in the gear mechanism. This is especially frequent after landscape work or in sandy soil.
Worn-Out Gears: Like any mechanical part, the internal plastic gears of a rotor head can wear down over time, eventually failing to turn the nozzle.
Incorrect Nozzle or Low Pressure: If water pressure is too low for the installed nozzle, it may not be enough to power the internal turbine that drives the rotation.

DIY Checks & When to Call a Pro:
First, try cleaning the head. You can often pull up the riser and hold it in place while the head is unscrewed. Check the filter screen at the base for debris and rinse it out. You can also try gently turning the head by hand to see if you can dislodge any grit.

If cleaning doesn’t work, the internal gear drive is likely stripped or broken. At this point, the entire sprinkler head needs to be replaced. While some homeowners are comfortable digging up and replacing a head, a professional can ensure the new head is the correct model, installed at the proper height, and adjusted for perfect coverage.

Misting: When High Pressure Wastes Water

Do your sprinklers look more like a fog machine than an irrigation system? That fine mist might look impressive, but it’s a major sign of inefficiency. Misting occurs when water pressure is too high, causing water to atomize into tiny droplets that evaporate or drift away before they ever reach the soil.

Key Symptoms:

Water exits the sprinkler as a fine fog or mist instead of droplets.
On windy days, a significant amount of water blows away from the target area.
The area around the sprinkler head gets very wet, but the outer edges of the pattern are dry.

Common Causes:

High Municipal Water Pressure: Many homes in the Sunnyvale area have street-level water pressure that is much higher than the 30-50 PSI (pounds per square inch) recommended for most spray heads.
Lack of Regulation: The system was installed without components to manage this high pressure.

DIY Checks & When to Call a Pro:
This is not a problem with a simple DIY fix, as it involves the fundamental hydraulics of your system. The solution is to regulate the pressure. This can be done in two main ways:

Install Pressure-Regulating Heads: Replace existing spray bodies with models that have built-in pressure regulators. These ensure each head operates at its optimal pressure.
Install a Pressure Reducing Valve (PRV): A single PRV can be installed for the entire system or for an individual zone to lower the pressure before it reaches the heads.

Choosing and installing the right pressure-regulating solution is a job for a professional. A technician can accurately measure your system’s static and dynamic pressure, recommend the most cost-effective solution, and ensure it’s installed correctly to protect your entire system.

Non-Uniform Coverage: The Patchwork Lawn

The goal of a sprinkler system is to deliver water evenly across every square foot of your lawn. When coverage is non-uniform, you’ll see a frustrating patchwork of lush green spots and dry, stressed areas. This indicates water isn’t being distributed correctly.

Key Symptoms:

Distinct dry patches or brown spots in the lawn.
Some areas are swampy while others are bone dry.
Water is visibly hitting driveways, fences, or the side of the house instead of the grass.

Common Causes:

Clogged Nozzles: A partially clogged nozzle will disrupt the spray pattern, causing it to spray erratically or not at all.
Misaligned Heads: Sprinkler heads can get knocked out of alignment by lawnmowers, foot traffic, or shifting soil. A tilted or misdirected head won’t cover its intended area.
Sunken Heads: If a sprinkler head sinks too low, the grass around it will block the spray.
Mixed Head Types: Using different types of sprinkler heads (rotors, sprays, MP rotators) in the same zone is a common installation mistake. They have different precipitation rates, meaning they put down water at different speeds, leading to over- and under-watering.

DIY Checks & When to Call a Pro:
You can perform a visual inspection. Check for clogged nozzles and clean them with a small tool or pin. Watch your system run and see if heads are pointed in the right direction; they are often easy to adjust by hand. If a head is sunken, you may be able to clear the dirt around it or add a small extension riser.

If adjusting and cleaning don’t fix the patchiness, you may have a larger design issue like mixed head types or poor head-to-head spacing. A professional irrigation technician can perform a “catch can test” to measure uniformity and diagnose these deeper issues. They can then re-nozzle, reconfigure, or redesign zones for optimal, water-saving coverage.

Simple Prevention for a Healthy System

A little routine maintenance goes a long way.

Seasonal Checks: Run your system manually each spring to spot obvious problems like leaks or broken heads.
Filter Cleaning: Regularly clean the main filter (if you have one) and the small filter screens in each head.
Head Adjustments: Periodically walk your property while the system is on to ensure heads are aligned and not blocked.

Frequently Asked Questions

Q: How do I know if I have an electrical problem or just a bad valve?
A: If a single zone isn’t working, it could be either. A key clue is if manually opening the valve (using the bleed screw) makes the sprinklers run. If it does, the valve itself is likely okay, and the problem is electrical (the solenoid or the wire leading to it). If it doesn’t, the valve is probably stuck or broken.
Q: What is the ideal water pressure for my sprinklers?
A: It depends on the head type. Most pop-up spray heads are designed for 30 PSI. Rotor heads typically work best between 40-50 PSI. Exceeding these pressures leads to misting and inefficiency.
Q: How often should I have my sprinkler system professionally serviced?
A: We recommend a professional tune-up at least once a year, ideally in the spring before you start your main watering season. This allows a technician to catch small problems before they become big, expensive ones and ensure your system is as efficient as possible for the dry months ahead.

Get Your Sprinklers Fixed Right in Sunnyvale

Don’t let sprinkler problems ruin your lawn or your water bill. Mr. Sprinkler Repair offers expert diagnostics and repair for homeowners throughout Sunnyvale, Wylie, Anna, and the surrounding communities. We provide same-week appointments and clear, upfront pricing so you know exactly what to expect.

Let our experienced technicians solve your sprinkler headaches for good. Call us today or book your appointment online to get your system running perfectly.