Garage Door Activates By Itself. LFM-20


(DanG) #1

2014-09-29 3:01:28.122 PM EDT 39 minutes ago DEVICE /physical switch on Garage Door switch is on

This is driving me nuts! I have a LFM-20 switch connected to my garage door and every so often it will activate to the on position causing the door to open or close.

I have contacted support numerous times and they claim the button on the device was pressed. This is not possible because it is installed in the ceiling. Back in April or May I replaced it thinking it was defective but it still randomly activates. The problem is obviously a safety and security issue but it happens so infrequently it is difficult to diagnose.

Anyone having issues with the LFM-20 switches on garage doors?


(Convinced ST will never be unbroken…) #2

No. But have you checked the event logs after this happens to see if SmartThings actually sent a command to actuate it? That would at least go some way to rule out if this is a problem with the device or SmartThings.


(DanG) #3

I posted the event log on the first line of my original message.
Because it reports “/physical” support claims the button was pushed. The button was never pushed on either switch and I find it very unlikely that I have two defective LFM-20 exhibiting the same behavior. I don’t know enough of how commands are sent so I really don’t know what to believe.


(Convinced ST will never be unbroken…) #4

I didn’t realize this device had an on/off button. Does it?

You say it is above the ceiling of your garage; what are the temperatures up there?


(DanG) #5

There is a recessed button that can be used to turn it on/off. It is the same button used to join/leave network.
Temperature has been ranging 60-80F. Today when it engaged it was 73F.


(Convinced ST will never be unbroken…) #6

Hmm… I’m running out of ideas. I suppose the next thing I would try would be to remove the device from SmartThings and see if it false triggers.


(zraken) #7

Hey, I had this happen to me once with a totally different System. Turned out that when I installed the Door switch the cable to the switch got pinched just enough that the 2 wires in the cable would randomly make contact and trigger the Door!
If you don’t have an obvious pinch point that you can fix just try replacing the cable.