I thought about this but realy the automation should always run. If you would like you can turn ON and OFF your automation using my other blueprint. 
Turn Light, Switch or Scene On & Off with Trigger Conditions. This will achive what you are trying to do.
Blacky 
Not sure if you have seen the 2 FAQ
Q: How do you set up a Derivative Sensor Helper?
A: Please follow these steps Click Here
Q: I have set up a âDerivative Sensor Helperâ but how do i set up the automation settings?
A: Please follow these steps Click Here
For me to look into it further could you also provide your 2 graphs of your âDerivative Sensor Helperâ, âFanâ and Humidity sensor like the example below of my showers today.
Blacky 
The fan spins to max speed every time I restart HA. I think it has to do with the HA restart safeguard. The humidity derivative is lower than the ON trigger. Not sure how to report this issue but I can reproduce if needed.
If I follow the trace, it eventually arrives at
service: homeassistant.turn_on
target:
entity_id: script.ventilatie_high
Is there a way to disable the safeguard?
id: '1695374273928'
alias: 'Shower: Bathroom Humidity Exhaust Fan'
description: ''
use_blueprint:
path: Blackshome/bathroom-humidity-exhaust-fan.yaml
input:
fan_switch:
entity_id: script.ventilatie_high
trigger: sensor.badkamer_humidity_derivative
fan_speed_low:
- script.ventilatie_medium
bathroom_humidity_sensor: sensor.badkamer_relhumidity
include_max_humidity: maximum_humidity_enabled
max_humidity: 90
fan_speed_off:
- script.ventilatie_low
include_fan_speed: fan_low_speed_enabled
rising_humidity: 5
falling_humidity: -2
time_delay: 15
bypass_options: []
include_bypass: bypass_disabled
It works when running Node Red, but i want to give your blueprint a try. I dont think its my sensors, as it doesnât even run when i manually tell it to run.
Ok, it worked after a restart, but selecting run still doesnât activate. I was under the impression that manually running the automation is like the âtriggerâ activating?
Hi, Just put in a extra RV sensor to check the one i want to use.
Strange thin is that the helpers are set up exactly the same but they give a different outcome. one calculates in 0.1% and the other in %??
it also takes 6 minutes to respond. can that go faster? or is that dependig on the RV sensor?
On the left i use a tuya zigbee sensor, and on the left a el cheapo RF sensor. But that eats batteries so i wanted a different sensor not eating batteries.
I guess changing sensor wil do the trick, but it is strange that the helper does strange things with the value?
This is a good place to report it⌠I will look into it and thanks for letting me know 
Edit: If required would you be interested in beta testing it?
Hey that is good news⌠I think you will love it now you got it up and running . It is a bit tricky and a bit of a love affair but once you nail it, it work well. I will have to remember that if someone else is having the same problem, thanks for letting me know and keeping me up to date.
No, see in your trace⌠it need a trigger, this is normal and how I designed it.
Enjoy
Blacky
This is probably what is going wrong. You need your humidity sensor to report a value every 60 seconds minimum. The derivative has a window of 3 minutes so it need 2 values within 3 minutes. @balk77 has a 10 second interval so it report realy fast and you are not standing in the shower waiting for the fan to come on. 6 min your shower will be over and that will be too slow. There are so many humidity sensors and best if you can adjust the reporting. Within a week I will show you one of my system as I have been meaning to do it but never got around to it. I think that will help a lot of people.
Blacky
Thank you. i also set a 10 second interval, but i guess the sensor does not update that often. I switched back again to the RF sensor, and ordered a huge amount of batteries with Amazon 
.
Still looking for the perfect sensor then.
It is the actual humidity sensor that need to report every 60 seconds min. The derivative has a window of 3 minutes. I will fully document my entire setup with the sensor and all the code so if you like you can copy paste. I will include photos and an easy step by step guide. Give me a week (it will probably be lest then, butâŚ) because I will have to pull some of it apart so you can see everything.
beta? sure, let me know. Is there anything else I could send you (traces for instance) that could help?
Thanks I just PM you for your trace line
Edit: I think I found it but will wait for your trace.
Hello. Please tell me what the reason may be. Xiaomi ordinary zigbee sensor, ordinary xiaomi zigbee socket. Automation is set up and running, while the time limit is 15 minutes. when 15 minutes have passed, the ventilation is turned off. The problem is that if the humidity is still high, the automation does not work the second time.
Thanks a lot for the answer.
When we are having back to back showers the humidity doesnât drop enough to trigger the automation again. For this it is best to also use the âMaximum Humidity Optionâ. In order for this to trigger the humidity must be below your setting and rise above it.
To use this feature you must enter in the humidity sensor you are using for the âHumidity Derivative Sensorâ. Then for summer and winter settings you have the option to enable the maximum humidity option as shown below and enter in a humidity % that suits you. If the slider doesnât allow you to enter in the setting you require then just simply type the value in.
Hope this helps
Blacky
thank you. Iâll try to do it
FAQ - Only Selecting Scripts
If only selecting a script in âFan Switchâ and âFan Speed - Low Speed Switchâ, it is recommended to enter in a dummy toggle helper to help the automation function correctly. It allows the by-pass and the built in Home Assistant restart safe guard option to function correctly.
If you have entered in a entity, example âFan or Switchâ then you donât need to enter in a toggle helper as the fan or switch will be sufficient. It only applies if you are just using scripts only.
Below show an example of just scripts entered and then scripts with toggle helpers.
Just Scripts 
Scripts with Toggle Helpers 
How to create a Toggle Helper
Go to Settings / Devices & Services / click on the âHelpersâ tab / click â+ CREATE HELPERâ and select âToggleâ.
In the name area, enter a name that best suits you. For this example we will put âBathroom Fan High Speed Toggle Helperâ and âBathroom Fan Low Speed Toggle Helperâ. Then click create for each toggle helper.
Now just enter in your toggle helpers into the automation as shown above.
Enjoy
Blacky
Back to FAQ: Click Here
FAQ - How Do I Use The Automation Link
This allows you to link your other automations so they will be automatically disabled. This is useful if you are using one of my other blueprints to control the lights, switches and or scenes in your bathroom and you would like to disable it when this automation is ON. It allows you to keep the bathroom lights ON when you are in the shower and your motion sensor is unable to detect motion.
If you are using my 
Sensor Light blueprint to control your lights in the bathroom sometimes when you are in the shower the motion sensor canât detect your movement (behind a shower screen or even glass) and your lights turn OFF when showering 
. Using this option allows you to disable the sensor light blueprint while you are in the shower so the lights will stay ON 
. When you have finished and the falling humidity % has been achieved or the safe guards set time has passed you can set a separate time delay that allows you time to dry yourself before stepping out where the motion sensor can detect you again. It will then turn the âAutomation Link - By-pass Controlâ OFF enabling your Sensor Light automation to function as per normal and your light will then turn OFF controlled by the sensor light automation
How to create a Automation Link - By-pass Control Toggle Helper and set it up
Below is an example on how to create the toggle helper and set it up between both automations.
Go to Settings / Devices & Services / click on the âHelpersâ tab / click â+ CREATE HELPERâ and select âToggleâ.
In the name area, enter a name that best suits you. For this example we will put "Bed 2 Ensuite - Bathroom Fan Automation Link - Bypassâ. I also selected and icon that suits me. Then click create.
Enter in the "Bed 2 Ensuite - Bathroom Fan Automation Link - Bypassâ toggle helper into the Sensor Light blueprint automation that controls your bathroom lights as shown below into option 1, 2 or 3. I have chosen to enable option â1 - Enable the By-pass - Turn lights ONâ.
Then in this blueprint âBathroom Humidity Exhaust Fanâ, enable the automation link option, enter in the "Bed 2 Ensuite - Bathroom Fan Automation Link - Bypassâ toggle helper into the âAutomation Link - By-pass Controlâ and set your time delay to your liking.
That is it, your done. Your sensor light automation will now be disabled when you are in the shower keeping your light ON
Enjoy
Blacky
Back to FAQ: Click Here
New Features 
Automation Link Option - This allows you to link your other automations so they will be automatically disabled. This is useful if you are using one of my other blueprints to control the lights, switches and or scenes in your bathroom and you would like to disable it when this automation is ON. It allows you to keep the bathroom lights ON when you are in the shower and your motion sensor is unable to detect motion.
For more information on the Automation Link Option Click Here
Bugs Fixes 
If you like this blueprint? Consider hitting the 
button in the top post
If you like my blueprints, and would like to show your support or just say thank you? Click Here 
Enjoy
Blacky 
