You walk out at noon in the middle of a July heat wave and the sprinklers are running — soaking the lawn at the worst possible time, watering the driveway, maybe kicking on a second time before dinner. Nothing changed in your settings, but the schedule is clearly wrong. This is one of the most common irrigation calls we get in mid-season, and the cause is almost always the controller, not the sprinklers themselves.
What makes an old timer run at the wrong time?
Older sprinkler timers lose their schedule after a power blip, a dead backup battery, or the daylight-saving change — and many ship with two or three overlapping programs that run back-to-back. The result is watering at the wrong hour, or twice a day. The permanent fix is a WiFi controller you set from your phone.
A traditional dial or button controller has no reliable memory and no awareness of the day around it. A handful of things quietly knock it off schedule:
- A power outage. Even a brief flicker resets the clock on many older units. If the backup battery is dead — most are, after a few seasons — the controller comes back up at 12:00 and runs everything off that wrong time.
- Daylight saving time. Older timers don't adjust. Twice a year the whole schedule shifts an hour and never corrects itself.
- Overlapping programs. Many controllers run separate A/B/C programs. If start times were set on more than one, the system waters, finishes, then starts again — that's the "running twice" complaint.
- An AM/PM mix-up. A schedule meant for 4:00 a.m. set as 4:00 p.m. waters in the heat of the day, every day.
- A stray extra start time. One accidental second start time per program doubles your run.
How do you check your current schedule?
Before you call anyone, it's worth a two-minute look:
- Check the time and date on the display first. If the clock is wrong, every scheduled start is wrong by the same amount.
- Find the start times for each program (A, B, C). You're looking for more than one start time, or a start time on a program you didn't mean to use.
- Confirm AM vs PM on every start time. This is the single most common mix-up.
- Match it to your watering bylaw. If your municipality runs odd/even or day-of-week rules, check the schedule lines up.
If the clock keeps drifting back to the wrong time after you fix it, the backup battery or the controller itself is failing — and that's the part worth replacing.
Why does this keep happening with older controllers?
Here's the honest part: you can reset an old timer, and it'll be right until the next power blip or time change knocks it out again. These units were never built to hold a schedule reliably or to know what the weather is doing. That's why the same call comes back every season.
A controller that won't run at the wrong time isn't a repair — it's an upgrade.
What's the permanent fix?
We install the Hunter HPC-400 (Hydrawise) WiFi controller. It reuses your existing valve wiring and sprinkler heads, so it's a swap at the controller, not a rebuild of your system. Once it's in:
- You set and check the schedule from your phone, anywhere.
- It keeps accurate time through power outages and handles daylight saving automatically.
- It uses local weather to skip or shorten watering when it's rained or it's about to — which keeps you onside with GTA watering bylaws and cuts waste.
- It alerts you if something looks off, instead of quietly watering the driveway for a month.
The water it saves is real: for a typical Newmarket property, a weather-aware controller saves up to $580 a year versus a manual timer. You can run your own numbers on our water cost calculator.
We're Hydrawise-certified (Hunter University trained), our upgrade pricing is published up front on our pricing guide, and the work carries our standard repair warranty. No surprise quotes. See the full smart controller upgrade, or if the rest of the system needs attention, our sprinkler repair page.
Which controller do you have?
If you'd rather set the schedule yourself first, we've written a plain-English programming guide for each of the common timers in York Region. Find yours below — the steps, and the "why is it watering twice?" fix, are in every one.
When should you call us?
If you're in Newmarket, Aurora, King City, Stouffville, Bolton, or Woodbridge and your sprinklers are running at the wrong time — or you're tired of resetting the timer every spring — we offer same-day repair through the in-season window across our York Region core.
Start with our AI diagnostic tool to describe what's happening (it'll often pinpoint the controller before we even arrive), call (905) 960-0181, or book online. If the AI's diagnosis matches what we find on site, you get one hour of repair labour free.
Frequently asked questions
Can I fix the schedule myself?
Often, yes — correct the controller's clock first, then remove any extra start times and double-check AM vs PM. If the time keeps resetting on its own after you fix it, the backup battery or controller is failing and needs replacing.
Why do my sprinklers run twice a day?
Almost always two overlapping programs (A and B, for example) each have a start time set, so the system finishes one cycle and immediately begins another. Clearing the unused program's start time stops it.
Will a new controller work with my existing sprinklers?
Yes. A controller swap reuses your existing valve wiring and heads — we're replacing the brain, not the system. It's a straightforward upgrade, not a re-installation.
Do smart controllers really save water under GTA watering bylaws?
They do, because they skip watering when it's rained and shorten cycles in cool weather instead of running a fixed schedule. For a typical local property that's up to about $580 a year — and it keeps you compliant with day-of-week and rain rules automatically.
Which controller does PJL install?
The Hunter HPC-400 (Hydrawise). We install it exclusively because it's reliable, weather-aware, and we're certified on it — so support and warranty stay simple.