Piston for First Alert CO/Smoke detector not working



I am in the process of migrating pistons from SmartThings over to Hubitat. The piston I am having trouble with doesn’t fire when its supposed to. Any idea why it isn’t firing?

I have 2 working devices installed on Hubitat. Here is a screen cap of one of my devices;


Set each of the "If"s above to Execute on condition change only and for Asynchronous execution method.
(While editing, click on each “If” then click on the gear icon in the dialog.
Task Execution Policy should be the first option. Click on the drop-down and select “Execute tasks on condition change only”.
Execution Method should be the third option. Click on the drop-down and select “Asynchronous”.)
The execution policy means that each “If” will execute only when an event that would effect the condition of the if occurs.
Asynchronous execution allows multiple statements to run out of sync (without waiting for the others to complete)


Your device values shows ‘test’ while your piston shows ‘tested’. Is that right?


Tried your suggestion and it still isn’t working. Set each if to Asynchronous and Execute on condition change only.

I have another piston that is setup the same way as to one I posted here only using leak sensors and it works as it should.

In order to simplify I made a test piston that only has one trigger. When I test the smoke detector the piston fires but never meets the if condition. I have changed condition from “is” to a trigger of “changes to” but nothing seems to work.


Yes. In WebCore the options are “clear”. “detected” and “tested”

You are on to something. I will try using an expression of “test” and see if that is the fix.


Looks like that’s your issue. Your log is comparing test to tested.


That’s it! I changed the if statement to test on expression “test” and it works!
So not sure if that is an issue with WebCore, the Hubitat driver, or the smoke detector is sending the wrong string.


I’m going to guess the driver. Maybe bring it up in the device thread if there’s one.


There is a difference between the drivers of SmartThings and Hubitat. SmartThings uses “tested” and hubitat uses “test”

Seeing that Hubitat has it coded for “test” and imbedded that into RuleMachine, I doubt they are going to change their driver in order to accommodate WebCore. So if the developer has an ear on this you may want to add that change in a future release.

The other odd thing is Hubitat’s “Notifier” app doesn’t even have a way to use a smoke detector as an option.


Hubitat generally uses “tested”

I expect this driver has a bug in it (I read other drivers, and saw them as tested

Which driver is it?


Generic Z-Wave Smoke/CO Detector

In Rm3 it does work so I’m not sure what the deal is. At least there’s a work around until it gets sorted out.