Irrigation oddity
 

With all of the rain in the area, I currently have my garden irrigation turned off.

Yesterday there was a very brief power cut - less than a second - and I heard the irrigation start up (zone 2).

I assume that the timer works by sending a pulse of electricity to a solenoid which opens the valve, then a second pulse to close it at the end of the allotted time, but how would a power cut (and maybe a small power surge when coming back on) do the same when the timer is in the OFF position?

I ask because, not being here full time, I don't want my irrigation to be triggered by a power cut (or lightning, as has happened once before) while I am absent.

Thank you

I don't know why your sprinkler system operated even though it was turned off. But, if it is the standard Hunter controller, there is also a power transformer (small black box) plugged into an outlet located inside of the panel where the Hunter controller is located. If you unplug the transformer, you will cut off all power to the sprinkler control system. That may be a better way to turn off the system when you leave town.

Thank you, retiredguy123, but I do want to keep the irrigation operational while I'm away - just working on the timer, not when SECO decides to put it on.

However, since we have no grass, your suggestion might be a good fall-back position.

The Rachio 3 smart irrigation controller offers 8 zone control via your smartphone. The Rachio 3 also evaluates numerous local weather predictions and automatically decides not to water if significant rain is predicted. It also adjust seasonal watering amount dependent on winter, spring, summer and fall.

If you add a rain sensor in addition to the rainfall prediction, it will control the irrigation in a proactive (weather prediction) and reactive (actual) manner.

Since the Rachio connects to your WiFi, you can control from anywhere.

Bottom line, it saves money on irrigation and provides control when away. Win-Win for cost and good option for a snowbird.

Cost is approximately $200 on Amazon and 1 hour to install.

Okay, but I am not sure it would have prevented the incident described by the OP. Also, some snowbirds don't maintain wifi in their house when they are away.

I ask my neighbor to allow my thermostat and sprinkler to connect to his wifi. Give him $20.
Win win for us both

You could buy a small ups (uninterruptible power supply) that many computers use. Best Buy, Amazon, or Wal Mart have them. Plug in the little sprinkler power transformer to that.
The sprinkler system should not be impacted by any more short power blips

Its not that expensive to maintain if youre only using it for this while away

Ding ding ding!
 

Correct response! Modems should also be on a UPS as well for continuous readouts to remote cellphones. Small UPS are worth their weight in gold for remote home owners. . .

network guy

No, there are no pulses of electricity. The timer sends a steady voltage to a solenoid to open for how many minutes you have the zone set for. After the timed minutes the timer turns off the voltage to the solenoid. With the timer in the off position the sprinkler system should not have started up. Electric spike or not with the switch off it should be OFF. Perhaps your timer is defective and needs to be replaced. I do not like the Hunter timer that came with the house. I did not find it user friendly to operate. Up north I have a Orbit 6 station timer. Easy install, easy to operate. Cost is about $45.00 and works great . I installed the Orbit timer here and couldn't be happier. Simple and easy to operate.

Thank you, Catalina36

The unit is 20+ years old so it may be time for a new one, although otherwise it works fine.

Thank you, Neils

I shall look into this

If this problem only occurred one time, why not test the system by turning the power off and on a few times to try to replicate the incident? It could have just been a one time occurance. If the timer works fine, there is no reason to replace it.

All good advice. I've been in the industry 40 years. Seriously consider a WiFi smart controller. I use the Netro brand at my place. Saves tons of money.

It has a battery backup in the control box. Usually 9 volts