Oh but I did update, and nothing happened, was the first major thing I tried after a day or two lol
The result is the same.
I will ask here the most stupid thing ever maybe, but just to rule it out: the automations are supposed to run by themselves, right, don’t have to configure some cron job or extra stuff ie when the trigger/conditions are met ? Might be some stupid operating mistake on my part, just thinking, but the docs seem to agree that it is not the case.
I always restart at least the automation, if not HA.
I also think it is the trigger but I am refraining myself, as I clearly don’t know exactly what it could be the issue.
No need for anything other than reloading automations after you have written it.
Tinkerer has told you why it is not triggering:
If your temperature is already above 20 it won’t trigger.
I also did try that and everything in between ie set a higher temperature, wait to climb to that - yesterday it was set at 25, when the room was at 24; 26/25, 27/26 - I really tried to figure this.
So now I set this test automation at above 25, when in room there are 24. Will wait to crawl, and report back.
I did reload the automation, and also restarted HA.
Later edit: to 24 now as the temperature dropped 
You could try this trigger instead:
trigger:
- platform: numeric_state
entity_id: climate.daikinap84451
attribute: inside_temperature
above: 20
Go to Developer Tools States and make sure the entity id and attribute are correct.
So I think we can conclude my experiment, the temp in the room is reported as 25 and stood an hour or so at 24. Automation was set at 24, when the temperature of the room was 23 Celsius. Didn’t touch anything in this period, log is empty.
It is not working as intended. A thought: maybe the “DaikinAP84451 Inside Temperature” sensor is not what I think it is, which is the room temperature (though it seems to behave accordingly), or at least somehow it can’t be used that way?
Edit: I also have a “DaikinAP84451” as you can see from the pic - will try that!
You have an automation in automations.yaml. If you share the YAML I’m sure we can help further.
It was posted above. Have to go, in the meantime will chill the hell out of the room, for further experiments. Tks!
Well good news, it works 
it just started this evening, and I kept thinking what I did different, as the trigger is pretty much the same. Thing is - this time I didnt’ touch anything in the interface or the remote; I remember after setting the automation I always somehow messed with temps in the dashboard, forcing the temperature to drop or increase, just to test. So the “tests” somehow screwed… the scope of tests.
Is this a thing? And I figured that it works somehow different than I would imagine, as it doesn’t check constantly? I mean if the temperature is at 24 in the room and the trigger at 24 - how is that working and why sometimes it’s not working when I set the trigger 1 celsius higher/lower?
Thank you all for the help and the patience!
Here is the end result now (what exactly is that “max: 3” doing there at the bottom?):
- id: '1625416471401'
alias: Daikin_AC_Attic_Start
description: Daikin_AC_Camera_Attic_Start
trigger:
- type: temperature
platform: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
above: 24
for:
hours: 0
minutes: 0
seconds: 0
milliseconds: 0
- type: temperature
platform: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
below: 17
condition: []
action:
- choose:
- conditions:
- type: is_temperature
condition: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
above: 24
sequence:
- service: climate.turn_on
target:
device_id: f9c4939f55a2c3b29341721af46814f8
- device_id: f9c4939f55a2c3b29341721af46814f8
domain: climate
entity_id: climate.daikin_ftxp25m
type: set_hvac_mode
hvac_mode: cool
- conditions:
- type: is_temperature
condition: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
below: 17
sequence:
- service: climate.turn_on
target:
device_id: f9c4939f55a2c3b29341721af46814f8
- device_id: f9c4939f55a2c3b29341721af46814f8
domain: climate
entity_id: climate.daikin_ftxp25m
type: set_hvac_mode
hvac_mode: heat
default: []
mode: single
max: 3
- id: '1625485504167'
alias: Daikin_AC_Attic_Stop
description: Daikin_AC_Camera_Attic_Stop
trigger:
- type: temperature
platform: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
for:
hours: 0
minutes: 30
seconds: 0
milliseconds: 0
below: 23
- type: temperature
platform: device
device_id: f9c4939f55a2c3b29341721af46814f8
entity_id: sensor.daikin_ftxp25m_inside_temperature
domain: sensor
above: 19
for:
hours: 0
minutes: 30
seconds: 0
milliseconds: 0
condition: []
action:
- service: climate.turn_on
target:
device_id: f9c4939f55a2c3b29341721af46814f8
mode: single
max: 3
Ah yes, I’d guess you’ve suffered from the same problem as many others - you’ve used the UI to build automations without reading the automation documentation. Admittedly, the device triggers aren’t obviously documented, but you have a numeric state trigger:
On state change of a specified entity, attempts to parse the state as a number and fires if the value is changing from above to below or from below to above the given threshold
All triggers work the same way - they fire when they become true.
In your case the sensor sensor.daikin_ftxp25m_inside_temperature has to be reporting a value of 24 or lower, and then report a value of above 24.
That’s for the run mode, and in the case of single it’s ignored as far as I know.