Quick answer: No. Turning the irrigation controller off prevents normal scheduled watering, but it does not remove water trapped in irrigation piping, valves or other components. Freeze protection depends on the system itself, not just the controller setting.
What the controller actually controls
The controller sends electrical commands to irrigation valves. Its off or rest setting stops automatic operation but does not drain the hydraulic side of the system.
Water can remain after the schedule is disabled
Piping, valves and low points can retain water depending on system design and drainage. That water may be vulnerable during freezing conditions.
Do not confuse shutdown with winterization
Seasonal shutdown includes addressing the irrigation water supply and water remaining in the system, not simply changing a timer setting.
See does a sprinkler system need winterization in Waxhaw? and our winterization FAQ.
