Repair guide · Seasonal

How to winterize a sprinkler system in North Texas

Every February our phone lights up with the same call: the backflow assembly split in a hard freeze and now there's a geyser at the side of the house. It's the most preventable repair in the trade, and winterizing a North Texas system is mostly about stopping exactly that. The good news: we don't have the brutal multi-month freezes that force a full compressed-air blowout up north. Our job is simpler, cheaper, and easy to get right.

Why the backflow is the whole ballgame

Your backflow preventer — the brass assembly standing a foot or so above the ground near your meter — is the most freeze-exposed plumbing on your property. Water expands when it freezes; brass doesn't. A single hard freeze on a charged, uninsulated assembly cracks the body or pops the test cocks, and you won't know until it thaws and starts spraying. That's a backflow repair or replacement running $[XXX]–$[XXX] — to prevent a problem that a $[XX] insulated cover would have stopped.

The North Texas winterization steps

1. Shut off the irrigation supply. Find the isolation valve feeding your system — usually on the backflow assembly or just before it — and close it. This stops water from refilling lines you're about to drain.
2. Relieve the pressure. Open the test cocks on the backflow a quarter turn to let trapped water drain and relieve pressure, then close them again. Run one zone for a few seconds after shutting the supply to bleed pressure from the lateral lines.
3. Insulate the backflow. This is the step that matters most. Use an insulated backflow cover (a foam or fabric pouch made for it) or, in a pinch, wrap the assembly in pipe insulation and a frost blanket. Don't seal the relief vent on a pressure-vacuum breaker — it needs to breathe.
4. Protect any exposed pipe. Above-ground PVC, riser stubs, and anything in an unheated space gets pipe insulation too.
5. Set the controller to skip the freeze. Switch the controller to "off" or "rain/seasonal" mode for hard-freeze stretches, so it doesn't run a zone during an ice event — which is both a code violation in most of our cities and a fast way to ice over your driveway.

Tools and materials

The freeze sensor: set-and-forget protection

Remembering to switch the controller off before every freeze is the weak link. A freeze sensor does it for you — it interrupts the system whenever the temperature drops near freezing. Texas has required rain/freeze shut-off technology on systems installed since 2009, and Dallas and McKinney require working sensors on all systems regardless of age. If yours is missing or dead, adding one is a quick job and the best insurance there is against a winter running-and-freezing disaster. We cover the wiring in our controller and wiring guide, and it's a standard part of controller repair.

Where this stops being DIY

The basics above are fair game on your own home. Call a licensed irrigator when:

Your backflow already split. A cracked assembly needs repair or replacement before spring, and in every city we serve the annual test won't pass until it's fixed. That's our backflow repair and replacement service — and we install insulation as part of the job, so it doesn't happen twice.

You want it done and verified in one pass. A pre-winter system inspection checks the backflow, proves the freeze sensor actually interrupts the system, drains what needs draining, and sets the controller — documented, so you're not guessing in January.

You're not sure what kind of backflow you have. Double check, pressure-vacuum breaker, and reduced-pressure assemblies winterize a little differently. If you're unsure, a quick look from someone who does this daily beats a guess that splits a casting.

Winterizing here isn't hard — it's a cover, a controller setting, and ten minutes of attention before the first hard freeze. Do it, and you skip the February call that everyone who didn't will be making. If yours already went, or you'd rather have it checked and done right, give us a call.