‎Alarm triggered when I close a window | SimpliSafe Support Home
mjm_3's profile

12 Messages

Tuesday, September 7th, 2021 12:29 PM

Alarm triggered when I close a window

I had a strange thing happen to me last night -- and I want to make sure I understand how the system works.

I have 4 windows in my master bedroom.  I opened each of them a little bit (about 3 inches) last night because the weather was nice and cool for the first time in months.  I know it was about 3 inches for each window because my windows have "stops" in them that you can enable to prevent the window from opening more than that as a security feature -- and I had those stops enabled.  Then I armed the system into Home mode.  I got the "Some of your entry sensors are open" notification when I armed it.

When I went to bed last night around 11:30pm, I walked into the bedroom and it felt like it was cool enough, so I wanted to close some windows.  The system was armed in Home mode at the time.

* I closed window 1.  The light on the sensor flashed and everything was good.
* I closed window 2.  The alarm activates, waking up everyone in the house.

I disarmed the system quickly from the keypad, then put it back in Home mode.  I thought maybe it was a sensor fluke -- because I was pretty sure that you're able to close sensors when the system is armed without setting off the alarm.  I left the other two windows open.

Fast forward to 2:30am.  I woke up because I heard my daughter crying.  I realized it was really cool in the bedroom, so I wanted to close the other two windows.

* I closed window 3.  The light on the sensor flashed and everything was good.
* I closed window 4.  The alarm activates AGAIN!

What am I doing wrong?  Do I really need to disarm the system every time I close a window?

729 Messages

3 years ago

I could be completely wrong, but the obvious (and potential) problem appears to be the second closing. I have never closed two windows in a row, but after reading about your issue, perhaps the system finds that behavior indicative of an intrusion attempt? That is the only thing that I can think of regarding a source. I may test the theory later.

12 Messages

3 years ago

Here's a response I received from SimpliSafe support. This doesn't sound right.

When you are your system in home mode with the windows open, and then close them the alarm will activate. This is because the system thinks the window was opened and closed.

If this was correct, why wouldn't closing windows #1 or #3 trigger the alarm? Also the SimpliSafe user guide (page 22) talks about arming the system with a sensor open, and it says nothing about closing the sensor triggering the alarm.

729 Messages

3 years ago

I could not duplicate the scenario today (and now it is too late).

The CS response is incorrect (from my experience). I arm my system in Home mode with a window open all of the time and close it without disarming the system. I have never triggered my system's alarm from the action. The unarmed sensor merely arms at closing without any disarming (and then rearming) of the Keypad. But I have never closed two windows back-to-back, so my best guess is it is a general bug or glitch in the firmware update or is only occurring in your system.

At times, new issues can crop up with SimpliSafe, and because your alarm went off after the second window closing in both instances, I am presuming that is the root cause. Again, I do not believe that the system should behave that way, but you can isolate the pattern to your alarm.

Community Admin


5.5K Messages

3 years ago

Hi mjm_3,

Your original thinking is correct. Entry Sensors will trigger an alarm when a. the system is armed, and b. it goes from a Closed state to an Open state.
If you're going from Open to Closed, it shouldn't be possible for it to trigger an alarm.

It might be helpful to take note of exactly which sensor is triggering, and when - especially in relation to when each of the sensors is closed. It might even be a totally different sensor that's triggering the alarm. You can check by viewing your Timeline event log in the app or online.
Also you want to pay attention to the flashing; one flash is for open, and two flashes is for closed.

Depending on the setup of your windows, could it be possible that when a window is physically fully closed, the sensors end up more than 2 inches away from their magnets? If so, then they would send the Closed signal briefly, and then signal Open again, thus triggering the alarm.

- Johnny M.
SimpliSafe Home Security

1.3K Messages

3 years ago

I tried multiple times with one of my systems and every time worked fine, but that's SS2 so the results may not be directly relevant if you have SS3.

That said, if it was a software/firmware bug I'd have though there would be more reports. I look at "page one" fairly often I this is a new one, far as I've seen anyway. Not to say it's impossible there's a bug, that's never happened before. ;)

Personally though, I'd be strongly inclined to check the magnet/sensor/window relationships and see if there is anomalous sensor triggering behavior indicated by how the LEDs react as you work the windows to their open and closed position.

It's possible some aspect of the sensor positions or window movement resulted in contact bounce that would cause the system to see the switch was closed then open again. If the system sees the sensor contacts change state even momentarily from closed to open to closed again it will be seen as a trigger event.

729 Messages

3 years ago

I will be watching this thread for an answer from mjm_3 (hopefully, there will be a follow-up). Also, I am curious to know if the alarm will still sound if the order of the two windows closing is reversed (i.e., changing the closure - 2 to 1 and 4 to 3).

64 Messages

3 years ago

For what it's worth I've had up to 7 door/window sensors open when arming in home mode, closed them in random orders and the alarm has never gone off. SS3

12 Messages

3 years ago

I plan to do some testing this weekend, and I'll report back with what I find.  I'm definitely a troubleshooter at heart, especially when it comes to technology.

I can tell you that it's not related to sensor placement and/or window rattling.  I was super diligent when I installed the sensors a few years ago -- the sensors are 5/16" away from the magnets when closed.  The windows are just a few years old and they're smooth closing vinyl windows with no movement/play.

12 Messages

3 years ago

OK, I think I figured out what's happening.  It seems like the sensors are detecting the close as another open -- because I wasn't closing the windows quickly enough I guess?

It seems like some sensors were more likely than others to get confused by this.  Two of them in particular.  But I was able to make it happen on all four, if I closed slowly enough.

Here's a video I recorded so you can see what's happening.  When the magnet gets within a couple inches, you see the double flash for closing.  But then the magnet gets even closer to the sensor -- and it "opens" and closes again (three consecutive flashes -- one for another open and two for another close).

Link to the video:

I still don't understand why the sensor would think a 2nd open is happening in this situation.  The magnet is still there...and it's getting closer to the sensor.  Perhaps these aren't super-precision devices.

I guess I learned my lesson.  Either slam the windows shut, or disarm the system before closing.

729 Messages

3 years ago

First, mjm_3, thank you for the follow-up, as it can always help others once you find the source of the problem.

(And thank you for the fantastic video to demonstrate it exactly!)

Secondly, while the exact scenario has never happened to me, I found years ago that whenever my windows were closed very slowly, the system would not arm that particular Entry Sensor. Then, I noticed that whenever my housekeeper was present, I would later find the symbol on the Keypad indicating an open sensor. The problem was them trying to gently close the windows as not to disturb me while working in my home office. So ever since, I have made sure to shut all windows with an Entry Sensor quickly. But I can understand when others are present (especially when they are sleeping, or it is late at night/early morning), there is a need to close windows as gently as possible.

Again, thank you for the continuation and especially the video!

1 Message

2 years ago

Did you figure this out?  This has happened to me 3x last week ( but not every night).

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