Should I Leave My Sprinkler Timer On After Winterizing?
Short answer from 30+ seasons in Metro Detroit: Yes—leave the controller ON after a proper blowout. For pump/lake/well systems, leave the controller ON but disable pump-start and shut the pump off at the electrical panel. For city-water systems, leaving the timer ON is the cleanest, simplest option.
City-Water Systems
- Leave controller ON (keeps time, Wi-Fi, schedules, logs).
- Optional: set a long Rain Delay / Pause / Standby if you want visual “paused.” Not required for safety.
- Lines are dry after blowout; a scheduled run simply opens a dry valve.
Pump / Lake / Well Systems
- Leave controller ON for clock/app access.
- Disable Pump-Start / Master Valve in the controller (or pump relay).
- Turn the pump breaker OFF at the electrical panel (belt-and-suspenders).
- Note those settings on the paper Winterizing Report I leave behind.
Why I Leave Controllers ON
- Clock & Wi-Fi stay correct (no spring “what time is it?” surprises).
- Schedules & zone names don’t get wiped by a long power-off.
- App/firmware updates keep working during the off-season.
- If a zone “runs,” there’s no water pressure in a city-water system—harmless. On pump systems, we’ve disabled pump-start so nothing spins dry.
Exactly What I Set at Winterizing
- Close irrigation supply, blow to a clean mist zone-by-zone.
- Open backflow test cocks so the shell can’t hold water.
- Leave the drain plug off or partially threaded for 24–72 hours in case the shutoff seeps.
- Controller stays ON. Optional: set a long Rain Delay if you want a “paused” badge in the app.
- Same safe blowout to mist, open test cocks, leave drain path.
- Disable pump-start / MV in the controller (global or per station).
- Switch OFF the pump breaker at the panel and label it.
- Controller stays ON for clock/app access over winter.
Brand Quick Paths (So You Can Check My Work)
- City: Leave ON; optional long Rain Delay (Advanced→Seasonal Adjust/Rain Delay).
- Pump: MV/Pump OFF in wiring/options; pump breaker OFF.
- City: Leave ON; optional System Off or Rain Delay.
- Pump: Disable Master Valve/Pump (global or per station); pump breaker OFF.
- City: Leave ON or use Standby Mode.
- Pump: Accessories → Pump Relay OFF; breaker OFF.
- Leave ON for clock/app; use the model’s Pause/Delay if desired.
- For pumps: disable master valve/pump output and switch the breaker OFF.
Not sure which you have? Text me a photo of the controller face and terminal strip; I’ll tell you exactly which toggle to flip.
Your 2-Minute End-of-Season Check
- Controller screen lit, date/time correct.
- Backflow test cocks open; drain area dry within 24–72 hours.
- If you see a program “run,” that’s fine—lines are dry.
- Controller ON; Pump-Start disabled.
- Pump breaker OFF at panel (tag it).
- No pump noise if a schedule runs. That’s the safety check.
Common Mistakes I See (Skip These)
- Turning the controller OFF all winter, then losing clock/schedules.
- Leaving a pump enabled in software while the app runs “Test All Stations.”
- Only flipping a controller setting for pumps but not switching the breaker OFF.
- Closing the #1 shutoff and not venting the backflow body (test cocks closed = pocket of water).
FAQ
No. On city-water systems the supply is closed and lines are dry. On pump systems, we’ve disabled pump-start and shut the breaker off.
You can, but I recommend leaving it ON so the time, Wi-Fi, and app access stay intact.
Optional. It’s a visual “paused” badge some folks like. Safety doesn’t depend on it.
Most modern controllers retain programs. Leaving the unit ON helps the clock resync when power returns.