How to Shut Down and Drain a Sprinkler System for Winter

DIY Sprinkler System Winterization: A Step-by-Step Guide

If you've never winterized your sprinkler system and don't have a manual, don't worry. The process is manageable with a systematic approach. Never use antifreeze in irrigation lines—it's unnecessary and environmentally harmful.

Winterization Steps

1. Locate and turn off the timer/controller – Disable all programs.
2. Find the main irrigation shut-off valve – Usually near the water meter or where the irrigation line branches off. Turn it off.
3. Locate the control valves – These are the valves with wires attached (often in a green box). Open the manual bleed screw or lever on each valve to release pressure and allow drainage.
4. Open any system drain valves – If present, open them to empty remaining water.
5. Optional: Use compressed air – For thorough drying, a professional blow-out with an air compressor is best, but gravity draining works for many systems.

If you can't find the timer or valves, trace wires from the controller or look for greener patches in the lawn indicating valve boxes.