Open window detection to turn off the thermostat (no window sensors)

hi, can someone help me to create a flow that turns off the thermostat if the temperature drops by 0.5 degrees in 5 minutes.

Which thermostats do you use? Many have a window open detection.
The flow you want is possible with variables, but you have to switch the thermostat on again when the window is closed.
I think it would be easier and more reliable if you got some window sensors. There are very cheap ones from Neo Coolcam.

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thanks for the answer, I use netatmo thermostats there are 9 thermostats one in each room I would like to avoid putting sensors because there are more than one window in the rooms but the biggest problem is the batteries to be replaced every time. with the window sensor I was able to create the flow without problems. my idea was to turn off the thermostat when the temperature drops by 0.3 degrees in 5 minutes and then turn it back on after a few hours, the problem I’m having in creating the flow is in the part ‘the temperature drops by 0.3 degrees’.

Netatmo message from 28.1.20

The smart radiator thermostats from Netatmo now have window-open detection, which ensures that the radiators are automatically closed when the window is open. Not only new devices benefit from the function, but once again also existing customers through a software update.

The thermostats react to the drop in temperature that occurs when the window is opened. If the radiator and the thermostat are too far away from the window and the temperature does not drop sufficiently, however, it does not react accordingly. A symbol displayed on the thermostat shows the user that an open window has been detected. The heating is switched on again when the closing of the window is detected by a rise in temperature or 30 minutes have passed.

Switching off the heating when the window is open can also be deactivated by the user. Either in individual cases by explicitly selecting in the app that the heating should continue, or across the board for all thermostats.

Although there seems to be a “window open” function (@Undertaker was faster than me :wink:), I created a few flows (sorry, only in German language and not checked!):

Flow 1

Flow 2 (corrected)

Flow 3

Flow 4

Flow 2 corrected

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yes it’s true netatmo has this function but only with radiator valves and not on the direct thermostat I don’t know why I wrote to them directly and they confirmed it to me, the problem is that I don’t have the valves I have a floor system

thanks for the flows I will try to recreate them, I will update you on the functioning

i recreated all your flows but i’m having problems with the netatmo app on homey i think it doesn’t work, it doesn’t update the temperature and if i try to change the temperature from app homey it doesn’t take it, i also tried to uninstall it but nothing, i wouldn’t want it it’s the fault of the recent update they made of the app. first I have to be able to solve this problem in order to use the flows you created.

I don’t use Netatmo wall thermostats myself, so I can’t say anything about possible problems.
But you can describe the problem in this thread, maybe someone can help you.

i managed to fix the problem with the thermostats, although i noticed that the current temperature is only updated every 15 minutes from homey to the thermostat, so i increased the temperature timer to 15 minutes.
I didn’t understand only in the second flow why do you multiply it by -1?

That’s a mistake, good catch.

It must be:
TV_TemperaturResult als {{TV_TemperatureOld - TV_TemperatureNew}} berechnen nach 1 sec

The variable TV_TemperatureOld should usually be larger than the variable TV_TemperatureNew. The result of this is a positive value.
The positive value is needed for flow #3:
TV_TemperaturResult is > than (+)0.3

@Leonardo_Soliera, I corrected flow no. 2 in the post above.

everything seems to work perfectly except for one thing, often the flow ‘1’ is not reactivated if the variable is not greater than 0.3 I cannot understand why I also put a delay of one second on the card that reactivates it in flow ‘3’

apparently the problem is when there are no variations between the old temperature and the new one, therefore result remains 0 and the variable does not change so the flow does not start

For me everything works perfect. Can you please share you’re flows? I guess you missed to set the action card Activate Flow 1 in flow '#3 in the Or section.


the flow is correct identical to yours, I am attaching the link here so you can check it: Shared Flow | Homey
Practically the problem is that the card that activates the flow ‘3’ says ‘if a variable changes’, but there are no temperature changes in the room the T.result always remains 0 and therefore the flow ‘3’ does not start and consequently does not reactivate the flow ‘1’. I managed to solve in this way, in flow ‘2’ I subtracted 100 and then added 100 to the T. result so that the variable always changes even if the result is 0. I attach the link of the modified flow ‘2’: Shared Flow | Homey
Doing so it would seem that everything works correctly even if there are no temperature changes in the room.

You are right. Flow 3 wouldn’t be triggered if this scenario happens:

Initial situation: Variable TV_TemperaturResult = 0

– Temperatur changes from 25.0 to 24.9 °C → Variable TV_TemperaturOld will be set to 24.9 °C and flow 1 will be deactivated and the timer will be started
– Timer has finished and the temperature hasn’t changed in the meantime → Variable TV_TemperaturNew will be set to 24.9 °C and the result of the calculation is 0
– Because the variable TV_TemperaturResult hasn’t changed, flow 3 will not be started = flow 1 will be not activated anymore

So this should be the solution (Flow 2):

Translation And… section:
Variable TV_TemperaturOld is not equal with (actually) Temperature (Netatmo Wall Thermostat)

I guess this will work now.

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I tested the flow but the problem was only partially solved with this flow, now in case of equal temperatures the flow ‘1’ is reactivated but the flow ‘3’ does not start yet as the variable ‘result’ does not change

Can you please show an example, with values?


@Leonardo_Soliera, that’s how it’s supposed to work.
No change in temperature, or if the temperature change is <= 0.3 °C, then Flow 1 will be activated again and nothing else will happen.
This is how a “Window Open Function” works based on the temperature measurement.
No change in temperature = no open window = no need to turn off the thermostat… :man_shrugging:t3:

I also don’t see any way to include the outside temperature, for example. So I think the only way is to install a window sensor. If you don’t want to do it for optical reasons, then I recommend a Sensative Strips Guard 700, which is mounted in the window frame so that it’s not visible when the window is closed. The battery lifetime is up to 10 years acc. info of the manufacturer. The radio protocol is Z-Wave, so therefore it must be ensured that there is a well-functioning Z-Wave Mesh. Btw., I have 16 of them in use (500 and 700).

Hello look the problem lies in the fact that the variable ‘result’ gets high Example if I try the flow ‘1’ with a temperature of 21.6 degrees it goes to set ‘t.old’ to 21.6 … then at the end of the timer it sets 't. New at 21.4 '(for example)
does the count ‘’ = 0.2 and up to here everything is ok, now the temperature ‘t.old’ reaches 21.4 which is equal to ‘’ and in theory the ’ t. Result ‘must come 0 but with the new card you put’ e ‘(t.old is not equal to the real temperature of the physical thermostat) it does not do the calculation so’ t. Result ‘always remains 0.2 and therefore is busted by 0.2 degrees when in theory it should be 0. Honestly I don’t know if it really depends on this new card but I end up with the variable’ result 'busted if I take this card out of the flow the variable is correct. I’m not sure what it depends on.
I do not know if I have explained myself well, if there is something you do not understand please ask, I know the sensatives I have 4 and in fact I use them on those windows but I have not bought others because after just 2 years they died amazon replaced them for me. luck but the battery life does not convince me given the price.
flow 1: Flow condiviso | Homey
flow 2: Flow condiviso | Homey
flow 3: Flow condiviso | Homey
flow 4 Flow condiviso | Homey

here you find the variables as described:

I guess I know what you mean what the problem is. There might be no change of the value of the variable TV_TemperaturResult. As result of this, flow 3 isn’t started, right?

What comes into my mind: The variable TV_TemperaturResult must be “reset” after the calculation.
Could you add this flow and check if it works?

– Timer Temperatura mansarda is started
– Deactivate flow 3
– Set variable T. Result Mansarda to 10 after 1 sec delay
– Activate flow 3 after 2 sec delay

What do you think?

Regarding the Sensitive Strips. I also had 2 Guard Strips that showed only 25% battery capacity after a relatively short time (<= 2 years). For both Strips I have received a replacement without having to return the old Strips. Now after about 2 more years the both Strips work still without any problems.
The other strips still show a battery capacity of 75 - 100% after 3-4 years. So I have no reason to complain.