Sprinkler System Startup: Step-by-Step Spring Guide (2026)

After a long winter, getting your lawn ready for spring is a top priority. A crucial part of that is waking up your irrigation system from its long slumber. A proper sprinkler system startup isn’t just about turning a valve; it’s a careful process to prevent damage and ensure your system runs efficiently all season long. Rushing this can lead to cracked pipes, broken heads, and costly water waste.

This comprehensive guide will walk you through every step of a professional grade sprinkler system startup, from initial inspection to final programming.

Before You Turn on the Water: Preparation is Key

A successful sprinkler system startup begins with a little prep work. Taking ten minutes to get organized and inspect your system can save you hours of headaches later.

Gather Your Tools and Materials

It’s frustrating to be halfway through a job only to realize you’re missing a tool. Before you start, gather everything you might need. A good checklist includes:

• Flat head screwdriver: You’ll need this for the small test cock screws on your backflow preventer.

• Sprinkler valve key: A long handled tool for operating underground shutoff valves in a meter box.

• Spare parts: It’s a fact that around 80% of irrigation systems need at least minor repairs after winter, so having extra sprinkler heads and nozzles on hand is smart.

• Fresh controller battery: Most controllers use a 9 volt or coin cell battery to save your settings during a power outage. Start the season with a fresh one.

Perform a Pre Start Damage Inspection

Winter can be tough on your sprinkler system. Water expands when it freezes, which can crack pipes, fittings, and valves. Before introducing water, walk through your yard and carefully inspect all the visible components.

Look for obvious cracks in sprinkler heads, valve boxes, and especially the backflow preventer assembly. Freeze and thaw cycles are so harsh that about 80% of sprinkler systems suffer some minor damage over the winter. Also, make sure the ground has thawed to a depth of at least 12 inches. Starting the system while the ground is still frozen is a common mistake that can lead to ruptured pipes. If you find significant damage, it’s best to schedule professional sprinkler repairs before you turn the water on.

Locate Your Main Shutoff Valve

Every irrigation system has a main shutoff valve that separates it from your home’s water supply. You need to know where it is. Common locations are in a basement or crawl space, or in an underground valve box near your water meter. This valve should have been closed all winter. Make sure you can access it and that the handle turns freely. Knowing its location is critical for the sprinkler system startup process and for any future emergencies that require a fast shutdown.

Turning the Water Back On: A Slow and Steady Process

This is the most critical phase of the sprinkler system startup. The key here is to reintroduce water slowly to avoid a damaging pressure surge known as water hammer.

Identify and Prepare Your Backflow Preventer

Your backflow prevention device (often a Pressure Vacuum Breaker, or PVB) is a critical safety feature. It prevents irrigation water from siphoning back into your home’s drinking water. If yours is due for annual certification or repair, book backflow testing and certification with a licensed BPAT. It’s typically a brass assembly located outside your house with two shutoff handles and a few small screws called test cocks.

First, you’ll need to close these test cocks. They were likely left halfway open for winterization. Use a flat head screwdriver to turn the slot on each test cock until it is perpendicular to the valve body. Next, make sure any bleeder caps or drain plugs on the system are reinstalled and tightened. Forgetting this step will result in an obvious, and very wet, leak.

Now, you will open the shutoff valves on the backflow preventer itself. Start by fully opening the downstream valve (the one leading to the sprinklers). Then, very slowly, turn the handle on the upstream valve (the one from the water supply). You should hear water filling the device. Some models may hiss or pop as air escapes, which is normal. Once it’s full, open the upstream valve the rest of the way. Both handles should now be parallel to the pipes.

Open the Main Valve Slowly to Prevent Water Hammer

Water hammer is a powerful shockwave created when water moving at high speed is forced to stop suddenly. It can easily crack pipes and fittings. To prevent this, you must open the main irrigation shutoff valve very gradually.

Take at least 30 to 60 seconds to turn the valve from the fully closed to the fully open position. As you do, you’ll hear water begin to rush through the main line, filling the pipes and pushing air out. This slow, controlled fill prevents the violent surge that causes damage. Once the valve is fully open, the sound of rushing water should stop. If it continues, you likely have a leak somewhere in the main line.

Testing and Fine Tuning Your System

With the water on and the main lines pressurized, it’s time to test each part of your system to ensure everything is working correctly for your seasonal sprinkler system startup.

Run Each Zone Using the Controller’s Manual Mode

Your sprinkler controller, or timer, has a manual mode that allows you to turn on individual zones one at a time. This is essential for testing.

Go to your controller and manually start Zone 1. Then, walk the area that this zone covers. This is called zone testing. Watch each sprinkler head to ensure it pops up fully and sprays in the correct pattern. Look for geysers from broken heads, dry spots indicating poor coverage, or soggy areas that could signal an underground leak. Repeat this process for every single zone in your system.

Inspect for Leaks at Valves and the Backflow Preventer

After running all the zones, perform a final leak inspection at the most critical points. Open the lids on your valve boxes. There shouldn’t be standing water or any signs of active leaking around the valves. A leaky valve can waste a tremendous amount of water over time.

Also, take another close look at the backflow preventer. There should be no drips or seepage from the handles, test cocks, or the top vent cap. Even a small drip can indicate a failing seal that needs attention. If you find leaks you can’t fix, it’s wise to call a professional. For homeowners in the Lubbock area, the licensed technicians at M&M Sprinklers can quickly diagnose and repair any system leaks. Prefer to hand this off each season? Consider a seasonal sprinkler maintenance plan for proactive inspections, adjustments, and priority scheduling.

Check the Operating Pressure

While you don’t necessarily need a pressure gauge, you can get a good sense of your system’s operating pressure by observing it. Sprinklers perform best between 45 and 60 PSI.

• Low Pressure Signs: Heads don’t pop up all the way or the water spray looks weak and doesn’t reach as far as it should. This could be caused by a leak, a partially closed valve, or too many heads on one zone.

• High Pressure Signs: The sprinklers create a fine mist or fog instead of droplets. This is inefficient, as much of the water evaporates or blows away before it hits the ground.

If you notice signs of pressure problems, adjustments may be needed, such as installing a pressure regulator or using pressure regulating sprinkler heads.

Adjust and Clean Sprinkler Heads

Now is the perfect time for fine tuning. Walk through your yard again and make any necessary sprinkler head adjustments.

• Straighten Tilted Heads: Make sure each sprinkler is sitting vertically in the ground.

• Adjust Spray Pattern: Turn nozzles so they water the lawn, not the sidewalk or driveway. Adjust the arc on rotor heads to ensure they are covering the correct area.

• Clean Clogged Filters: If a head is spraying poorly, a clogged filter is often the culprit. Unscrew the nozzle to access the small filter screen inside the pop up stem. Rinse it clean and reinstall it. A clean filter can make a huge difference in performance.

Finalizing Your Sprinkler System Startup

Your system is now awake, tested, and tuned. The last few steps involve setting it up for automated, efficient watering throughout the spring.

Program Your Controller for the Season

Your lawn’s water needs are different in the cool, wet spring than in the hot, dry summer. Update your controller with a spring friendly watering schedule.

Start by setting the correct date and time. Then, program your watering days, start times, and the run time for each zone. Early morning is the best time to water. A good starting point for spring might be watering two or three days a week. Many modern controllers have a “seasonal adjust” feature that lets you easily reduce all run times by a percentage (e.g., set it to 60% of your summer schedule). If your current controller is outdated or unreliable, ask about irrigation system installation and upgrades to add smart control and better water efficiency.

Don’t Forget the Final Details

Two small but important items finish off your sprinkler system startup:

1. Replace the Controller’s Backup Battery: As mentioned earlier, this battery saves your program during a power failure. Professionals recommend replacing it every 6 to 12 months, and spring startup is the perfect time to do it.

2. Clean Your Weather Sensor: If you have a rain or rain/freeze sensor, make sure it’s free of leaves, spiderwebs, and other debris. A clogged sensor may not work correctly, causing your system to water in the rain.

A thorough sprinkler system startup ensures your lawn gets the water it needs efficiently, saving you money and preventing headaches. If you feel overwhelmed by the process or discover a problem you can’t solve, don’t hesitate to reach out for professional help. The experienced team at M&M Sprinkler and Tree Services, including licensed irrigators and ISA‑certified arborists, provides comprehensive startup services to get your system in perfect shape for the season.

Frequently Asked Questions about Sprinkler System Startup

When is the best time to perform a spring sprinkler system startup?

The ideal time is after the last hard frost has passed and the ground has thawed to a depth of at least 12 inches. Check your local forecast; if temperatures are still dropping below freezing at night, it’s best to wait.

What is the most common mistake people make during startup?

The most common and damaging mistake is opening the main water valve too quickly. This creates a pressure surge called water hammer that can crack pipes, valves, and sprinkler heads. Always open the main valve very slowly over 30 to 60 seconds.

Can I just turn my system on and skip this process?

It’s highly discouraged. Skipping the inspection and slow pressurization process puts your entire system at risk of damage from undetected leaks or water hammer. A proper sprinkler system startup is a crucial preventative maintenance step.

What should I do if a zone doesn’t turn on at all?

If a zone doesn’t activate from the controller, the issue is likely electrical. It could be a faulty solenoid on the zone valve, a bad connection, or a broken wire. Troubleshooting these issues can be complex, and you may want to contact a professional irrigator for help.

How much does a professional sprinkler system startup cost?

Costs can vary depending on your location, the size of your system (number of zones), and whether any repairs are needed. Most companies charge a flat fee for the basic startup service and will provide an estimate for any necessary repairs they find.