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TASK NO. 089 Preventive

Winterize a sprinkler irrigation system

Outdoor & Deck
Trigger
Before first hard freeze
Who does it
DIY or Pro
Est. time
1-2 hrs
Est. cost
$0-100 (pro blow-out)
Difficulty
●●○○○
Step by step
  1. Shut off the water supply to the irrigation system at the backflow valve.

  2. Turn off the automatic controller or set it to 'rain mode' / off.

  3. Open drain valves on the system if it has manual drains.

  4. For systems without drains, a pro uses an air compressor to blow out remaining water (recommended, since DIY blow-outs risk pipe damage from over-pressurizing).

  5. Insulate the backflow preventer with a foam cover.

Questions to ask your pro
  • Do you use compressed air blow-out, and what PSI do you use for my pipe material—PVC versus polyethylene?
  • How many passes per zone do you make to ensure all water is expelled?
  • Will you check for broken heads, leaks, or valve issues before winterizing?
  • Do you document which zones were serviced and confirm each is clear?
  • Will you properly shut off and drain the backflow preventer, and insulate it if needed?
  • When should I schedule spring startup, and do you offer a combined annual service package?
Video guide
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