# Low Temperature Alarm

**URL:** <https://community.homey.app/t/low-temperature-alarm/57016>\
**Category:** Questions & Help\
**Created:** [December 22, 2021, 12:02am UTC](https://community.homey.app/t/low-temperature-alarm/57016 "2021-12-22T00:02:07Z")\
**Posts on this page:** 10\
**Page:** 1

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**Author:** ![Kjell\_B](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/kjell_b/32/48647_2.png) [@Kjell\_B](https://community.homey.app/u/Kjell_B)\
**Post date:** [December 22, 2021, 12:02am UTC](https://community.homey.app/t/low-temperature-alarm/57016/1 "2021-12-22T00:02:07Z")

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I am relatively new on the platform and have onboarded a lot of stuff but one thing puzzles me. I have a big house and a garage and a Storage space for bicycles ++. I have bought a bunch of aqara Temperature sensors that correctly give me temperature readings from the rooms,

Since it is winter i wanted to create a low temperature alarm so that i Get a heads up if some rooms getting close to zero. I searched for apps and other smart solutions to do this without any luck. Can someone point me in a smart direction other than creating one or two flows pr. Sensor. There must be a smatter way than that ?

🙂 Kjell

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**Author:** ![DirkG](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dirkg/32/118897_2.png) [@DirkG](https://community.homey.app/u/DirkG)\
**Post date:** [December 22, 2021, 8:51am UTC](https://community.homey.app/t/low-temperature-alarm/57016/2 "2021-12-22T08:51:35Z")

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You can do something like this:

 ![image](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/7/e/7e3978aa23ef5dce136beed203235897ba5e20c0.png)

English translation:

**If…**  
– A sensor value has changed (Sensor type: Temperature)

**And…**  
– Temp. \< 2°C  
– Area is Garage  
or  
– Temp. \< 2 °C  
— Area is Storage space

**Then…**  
– Push notification

In the push notification you can define which sensor, which area is below 2 °C.

Another solution can be to use the [\< group \>](https://homey.app/en-us/app/com.swttt.devicegroups/%3C-group-%3E/) app (if you don’t use the Homey bridge). With this app you can group several devices to one device. If you group the necessary temp. sensors to one sensor, then the flow should be like this:

**If…**  
– The temperature has changed (of the grouped sensor)

**And…**  
– Temp. \< 2°C

**Then…**  
– Push notification

Or the better flow is:

**If…**  
– Temperature becomes less than 2°C

**Then…**  
– Push notification

In these push notifications you can’t define which sensor, which area is below 2 °C like above.  
If you want to know which sensor is below 2 °C you can create a push notification like this:  
Temperature in the garage is actually (value of the sensor in the garage) °C.  
Temperature in the storage room is actually (value of the sensor in the storage room) °C

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**Author:** ![Kjell\_B](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/kjell_b/32/48647_2.png) [@Kjell\_B](https://community.homey.app/u/Kjell_B)\
**Post date:** [January 4, 2022, 3:34pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/3 "2022-01-04T15:34:15Z")

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Hi,

Thank you for the feedback. Been offline during christmas so sorry for the delay here. I tested the group app and that looked promising but i could only define “Mean Average” and that will not do the job. Change in sensor value is a good idea that semmes to work. Much easier that several flows for each sensor. But will it stress the processor since every sensor change will trigger the flow?

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**Author:** ![DirkG](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dirkg/32/118897_2.png) [@DirkG](https://community.homey.app/u/DirkG)\
**Post date:** [January 4, 2022, 6:59pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/4 "2022-01-04T18:59:14Z")

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> [@Kjell\_B](#):
>
> “Mean Average”

Homey App → More → Apps → \< group \> → Configure app → Category „Sensor“ → select the right group → change „Temperature is“ to „the lowest value“

> [@Kjell\_B](#):
>
> But will it stress the processor since every sensor change will trigger the flow?

It’s only possible to „group“ 3 sensors with this kind of flow, because it’s possible to use 2 „or“ only. And no, this will not stress the CPU.  
Of course, the „better“ flow with less trigger actions will be „Temperature becomes less than…“.

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**Author:** ![Kjell\_B](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/kjell_b/32/48647_2.png) [@Kjell\_B](https://community.homey.app/u/Kjell_B)\
**Post date:** [January 23, 2022, 11:41pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/5 "2022-01-23T23:41:28Z")

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Fantastic, that worked. How could i miss that. Just what i needed. Now i can group all the rooms i want to check into one group and one flow to notify me. Now i just have to figure out how i make the flow stop notify after the first notification. One message is enough 🙂

Kjell

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**Author:** ![DirkG](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dirkg/32/118897_2.png) [@DirkG](https://community.homey.app/u/DirkG)\
**Post date:** [January 24, 2022, 8:14am UTC](https://community.homey.app/t/low-temperature-alarm/57016/6 "2022-01-24T08:14:12Z")

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There are different possibilities, but I guess this will be the best one.  
First a boolean variable (Yes/No) must be created.

_ **Flow 1** _  
**If…**  
– Temperature becomes less than 2 °C

**And…**  
– Variable “LowTemp” is **NO**

**Then…**  
– Push notification  
– Set variable “LowTemp” to **YES** with 1 sec delay

_ **Flow 2** _  
**If…**  
– Temperature becomes more than 3 °C (or whatever)  
**And…**  
– Variable “LowTemp” is **YES**  
**Then…**  
– Set variable “LowTemp” to **No**

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<div class="post-metadata">

**Author:** ![Kjell\_B](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/kjell_b/32/48647_2.png) [@Kjell\_B](https://community.homey.app/u/Kjell_B)\
**Post date:** [February 1, 2022, 7:56pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/7 "2022-02-01T19:56:29Z")

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Played around a bit with your suggestion. And this is great. Learnd a lot from this. Thank you

🙂

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<div class="post-metadata">

**Author:** ![DirkG](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dirkg/32/118897_2.png) [@DirkG](https://community.homey.app/u/DirkG)\
**Post date:** [February 2, 2022, 10:31am UTC](https://community.homey.app/t/low-temperature-alarm/57016/8 "2022-02-02T10:31:12Z")

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I’m happy to hear that I was able to help.

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**Author:** ![Stefan\_Pettersen](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/stefan_pettersen/32/56552_2.png) [@Stefan\_Pettersen](https://community.homey.app/u/Stefan_Pettersen)\
**Post date:** [August 15, 2022, 8:10pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/9 "2022-08-15T20:10:20Z")

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Hi. I’m wondering if there is a way to program the sensor so that it triggers a notification or alarm if temperature reaches a set temperature and does not return to normal in x minutes. Is that possible?

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**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\
**Post date:** [August 15, 2022, 8:56pm UTC](https://community.homey.app/t/low-temperature-alarm/57016/10 "2022-08-15T20:56:39Z")

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Something like this  
(I use Chronograph as timer)

- Flow 1  
When…  
-temperature sensorA has changed  
And…  
-temperature sensorA is greater/less than xx  
Then…  
-start or replace timer MonitorSensorA with a run time of x minutes  
Else…  
-pause timer MonitorSensorA

- Flow 2  
When…  
-timer MonitorSensorA has ended  
Then…  
-send alert