Sprinkler Blowout in Greeley, CO

Aim for the second half of September, and treat the end of the month as the deadline. The first hard freeze along the Front Range regularly lands in the first half of October and can arrive earlier without much warning. Waiting for the forecast is a poor strategy because irrigation contractors book solid in the last two weeks before a freeze, so the appointment you want may not be available when you finally decide you need it. The cost of blowing out two weeks early is a little less lawn watering in a month when the grass is going dormant anyway. The cost of being two days late is a cracked backflow assembly.

It depends on how your system was installed. A system with properly placed manual or automatic drain valves at every low point, on ground with reliable fall, can in principle be drained. Very few residential systems here actually meet that description, and even those retain water in the backflow assembly and in any section that has settled over the years. Compressed air clears what gravity cannot reach, which is why it is the standard method in a climate that freezes hard. If you are unsure which kind of system you have, that is itself a reason to have someone look at it once.

It is priced by zone count and system complexity, and it is one of the least expensive appointments in plumbing. What moves it is the number of zones, whether the compressor has to be moved around a large or awkward property, and whether the backflow assembly needs draining and testing at the same time. Ask whether the quote includes the backflow, since that is the component you most want handled properly. Compare the figure against replacing a cracked backflow assembly and the decision makes itself.

Only if it moves enough air. This is a volume job rather than a pressure job, and the compact compressor most homeowners own cannot sustain the airflow needed to carry water down a long lateral line. It will clear the first stretch, produce a satisfying mist, and leave the rest of the zone wet. If you want to do it yourself, rent a proper compressor for the day, run each zone in short bursts at moderate pressure, and stop as soon as the discharge turns to mist. Running dry air through a rotor head for too long generates heat with nothing to cool it and destroys the internal gears.

Shut the irrigation isolation valve immediately, open the backflow test cocks, and drain whatever you can reach by hand. That takes the pressure off the most expensive component and gives expanding ice somewhere to go. Then leave it and book a blowout rather than turning the system on to check for damage, repressurizing a line that has a hidden split turns a small crack into a flooded yard. A missed winterization does not automatically mean damage, particularly after a brief overnight freeze, but it does mean the system should be checked before it is charged again.

The backflow preventer, by a wide margin. It sits above ground, it is a brass casting with an internal assembly, and it holds water that has nowhere to drain. When that water freezes, the casting cracks rather than a seal failing, so the fix is a replacement assembly plus a fresh test. After that come above-ground pipework and valves in shallow boxes, then sprinkler heads, which crack at the body and weep once the system is repressurized. Controllers and wiring survive cold fine, but not the repeated flooding and freezing that a cracked valve produces.

It should be, and you should confirm it is. The assembly needs to be drained manually through its test cocks rather than simply blown through, and the test cocks should be left partly open over winter so nothing can be trapped inside. Ask specifically whether draining the backflow is included, because it is the highest-value part of the visit. In many jurisdictions the assembly also has to be tested by a backflow tester when the system is reactivated, so it is worth asking about that at the same time.

Yes. After the blowout, the dedicated irrigation isolation valve stays closed all winter, which is what guarantees the system cannot be accidentally recharged during a warm spell. The controller should be switched to off rather than left running a schedule, and if it has a rain-delay or seasonal-off mode, that is the correct setting. Leave the backflow test cocks partly open, and if any manual drain valves exist, leave them open too. The principle is simple: nothing in the system should be able to hold water.

Wait until hard freezes are genuinely finished, which here often means well into May rather than the first warm stretch in April. A late freeze on a charged system undoes the entire winter of caution. When you do reactivate, open the isolation valve slowly: a quarter turn, wait for the sound of filling to stop, then a little more. Filling a large system should take minutes rather than seconds, because a dry network filled at full main pressure produces a surge that finds every weak fitting at once. Close the backflow test cocks before you start.

Run every zone manually and stand there watching it, which is the step almost everyone skips. Winter damage shows itself in the first few minutes: heads that do not rise, heads weeping at the base, a geyser where one has snapped off, dry patches suggesting a broken lateral, and wet spots appearing where no head is installed. Check the backflow assembly for weeping at the same time. Finding a fault while you are standing in the yard is far better than discovering it later from a water bill, and most of what winter breaks is inexpensive to fix if you catch it before the system runs unattended all summer.