I have a flow for when the humidity increases by 8% the fan turn on . It works perfectly. But randomly the sensors (xiaomi aqara) lose communication with homey, and report 0% humidity, and when they regain communication my flow is activated.
Any ideas how I can prevent it from activating after reporting that 0% humidity?
You could add an additonal condition in the âandâ where humidity is NOT 0, since that is unlikely to be a valid humidity.
Dont think that will work, the humidity has just changed (thats what triggered the flow) so it will not be 0 anymoreâŚ
But you probably stored the previous value too (you need it to calculate if it increased) so use that tag in the AND
I use 2 flows:
1
when sensor humidity change
Then set number variable humidity(i use better logic)
2
When number variable humidity increased min by 8
And variable humidity is greater than 50
Them turn on fan
Donât work. How can i memorice the 0 value to use as condition in ââandââ condition?
Edit: i will try 2 variables:
1
when sensor humidity change
Then set number variable humidity 1
2 when var humidity 1 change
And var humidity 1 is not 0 (or less than 30 fe)
Then set var humidity 2
3
When number variable humidity 2 increased min by 8
Then turn on fan
Can I ask what kind of environment you are measuring?
I guess its a steamroom?
At least humidity >50 is pretty high for a normal room, especially in winter.
And increasing humidity with 8, within two measuring points, that a huge step.
Iâm measuring the humidity in the bathroom. In Galicia (Spain) rains a lot. Humidity less than 50% is imposible. Only in very dry summers.
The humidity only increase by 8% when the steam of hot water.
You already do in flow 1âŚ
But this variable will follow the humidity
Try this:
1
when sensor humidity change
Then set number variable humidity(i use better logic)
But add a delay of 1sec
For the second flow use the humidity not the variable
2
When sensor humidity increased min by 8
And variable humidity is greater than 50
Then turn on fan
These two flows will run at the same time
When value is 0 only flow1 will run the THEN
When the humidity is measured again the second flow will not run vpbecause the variable is still 0 (and will change 1 second later)
If your humidity sensor has larger interval for measuring you can increase the delay
This should do it in one flow, it is a modified version of mine. Beware that âLuchtvochtigheidâ is used of two sensors, but you really canât tell which is which in the flow. (Actually, one is the local variable, the other is the sensor in the other room). You have to guess which is which 
@FKey ,
1 I think that the delay of 1 second may not work, I donât know how long it fails when it reports 0.
2 I donât have that card in the when section, only âthe humidity has changedâ, that is why I use the variable.
@Edwin_D ,
I just made the flow as you said, the part of turning on the fan works, now I just need to not turn them on when the connection fails. Need to waitâŚ
I see you use the aqara sensors. You use the Aqara & Xiaomi Smart home (Zigbee directly to homey) app or the Mi Homey (wifi&gateway) app?
thanks to both!!
I have the aqaraâs linked directly to homey, I do not own the aqara bridge.
The flow I provided should not trigger when the connection fails, because it ignores any case when a humidity value is 0. So if the bathroom reports 0, the flow stops in the and. If the bathroom humidity changes when the other room is 0, the flow stops in the and.
The same should apply if you copy the humidity to a variable - just donât do that when it is 0, humidity is never 0. It will only do itâs work when both values are correct.
There is a small problem in the case that the other room would come back from 0% humidity to a value that is more than 8% below the bathroomâs humidity. Because as long as the bathroom humidity doesât change, nothing happens. In that (probably rare) case you should consider a similar flow that checks if you need ventilation when the other roomâs humidity changes.
The delay is added to prevent that the variable is updated, before it is used by the second flow.
The 2 flows will run at the same time. But you want to prevent that the second flow is using the variable and that variable is just updated a ms beforeâŚ
