🚿 Bathroom Humidity Exhaust Fan

[Blacky]

@vicusj

Looks like your getting the hang of it. I have marked up your graph below. I have indicated where I think your shower was in green. I have also given you starting points of 2 for rising and -1.5 for falling. When falling triggers you can see your time delay. You will need to adjust this so when the fan turns OFF your humidity is okay. At the top I have shown a time line of what happens if the safe guard is used, if the falling humidity it triggered then safeguard is canceled. Seeing it on a graph can really give you a better understanding of how it works and how to adjust your settings.

Hope this helps you.

Blacky

[vicusj]

Awesome, thank you Blacky! I think I am getting things dialed in by having the fan behaving as I’m expecting it to.
I built a card with several graphs to analyze the various related data points and came to the conclusion that I was literally drowning my poor humidity sensor on the original location I had it as it got some water spray on and struggled to recover. I think I have now found a sweet spot for it, but will keep on monitoring.

Thanks again, no doubt I will be back with more noobie questions

[nutbox76]

Hi,
First off thank you for a great blueprint which was working but now for some reason has stopped working and for some unknown reason my derivative sensor is giving me strange readings and the fan doesnt activate at all when humidity is high.
As you can see from the picture the derivative is reading very low numbers and has been like it for a few days the only things ive done is the usual updates for HA.
I have tried deleting a redoing the sensor to no avail .

[Blacky]

@nutbox76

Welcome to the community.

Looking at your graph with a large range it is hard to see what is going on. Try and reduce the range so you can focus on the shower. Below is one of my showers just the other day.

Make sure your humidity sensor is reporting correctly as that is where I would start. Then maybe redo (or check the settings) your derivative sensor if it look like it is not following your humidity sensor.

Blacky

[isaackehle]

Good day to you and everyone here.

Is there an option to delay the fan from turning on once the humidity level is reached? This would be very helpful when the steam shower is being used, and having the steam sent straight out of the vent defeats that purpose.

I could trigger an external automation that would set the ‘disable automation input’ for a chunk of time. Though it would be a good solution to incorporate such a delay.

Thanks!

[Blacky]

@isaackehle

Never thought about the steam shower

@isaackehle

I could trigger an external automation that would set the ‘disable automation input’ for a chunk of time. Though it would be a good solution to incorporate such a delay.

Could you try this and see if it works for you. I am guessing you are going to need it to run normally but when you have a steam shower you will need to do something to tell the automation you are having a steam shower. As a test before you go crazy and maybe use your voice to toggle the helper could you create a toggle helper and set up the bypass as shown below.

I created a toggle helper called “Steam Shower Toggle Helper”. What will happen is when you turn ON the “Steam Shower Toggle Helper” the fan will turn OFF. Then we enabled the bypass auto OFF and set the time for 15min. You don’t need to do this you can manually turn OFF the “Steam Shower Toggle Helper” if you like. If you do use the auto OFF it will then turn the “Steam Shower Toggle Helper” OFF in 15min as per the setting.

This is a link to another blueprint of mine but is shows you how to create a toggle helper if you are unsure. Click Here

Let us know if this works for you.

Blacky

[isaackehle]

Thanks for the help!

These two are how the blueprint is configured now.

This is the way to enable the bypass with a double click of a Zooz scene controller.

This is a simple toggle from a physical device to the input_boolean.

I’ll give this config a try next time I use it.

[Blacky]

@isaackehle

@isaackehle

Thanks for the help!

No problem.

@isaackehle

This is the way to enable the bypass with a double click of a Zooz scene controller.

Normally double click buttons have no state. So what we need to do is set it up so your double click action controls a toggle helper similar to turning on a light or a switch but use a toggle helper. You then use that toggle helper in the automation as the automation must see a state of ON / OFF and double click buttons normally don’t provide that information to Home Assistant.

Blacky

[isaackehle]

@Blacky

Normally double click buttons have no state. So what we need to do is set it up so your double click action controls a toggle helper similar to turning on a light or a switch but use a toggle helper. You then use that toggle helper in the automation as the automation must see a state of ON / OFF and double click buttons normally don’t provide that information to Home Assistant.

Right, and that makes total sense. The Bath fan disable when double click automation. is doing what you described. I didn’t include this level of detail before. The MBSSB is a helper that goes into your blueprint instance. From there, I set the instance to auto turn off the helper after 15 minutes (I think that was in your original screenshot).

[Blacky]

New update 2.4

New Feature

• Collapsible Sections - Added collapsible sections to the blueprint. This enhancement improves the blueprint user interface by making it cleaner and more organized, allowing sections to be collapsed.

  This feature was introduced in Home Assistant 2024.6, so you must have this version or later for the blueprint to work.

Maintenance

• We have updated input descriptions to better help understand what they do.

Code Clean Up

• Cleaned up code for reliability that could cause a bug.

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

[GTunney]

Sorry for being a complete idiot here but can you explain a bit the purpose of the derivative sensor?

I’m trying to determine if this blueprint is for me.

I added a derivative sensor for one of my humidity sensors (master bedroom) just to test and see its behaviour. I noticed over night the humidity within the room crept up as we slept to almost 80% but the derivative sensor never crept over 0.4%.

I’m guessing the derivative is best served for a spike in humidity instead of a gradual increase? My worry is during a shower derivative kicks in the fan, lowers humidity and then turns off however the humidity then starts to gradually increase to a point the fan should kick in again but doesn’t because the derivative is too low.

[sparkydave (🇦🇺 Dave)]

@GTunney

I’m guessing the derivative is best served for a spike in humidity instead of a gradual increase? My worry is during a shower derivative kicks in the fan, lowers humidity and then turns off however the humidity then starts to gradually increase to a point the fan should kick in again but doesn’t because the derivative is too low.

That’s pretty much it. You simply adjust the off-delay to prevent the fan from turning off due to the decrease in humidity that it causes by being on.

[Blacky]

@GTunney

@GTunney

I added a derivative sensor for one of my humidity sensors (master bedroom) just to test and see its behaviour. I noticed over night the humidity within the room crept up as we slept to almost 80% but the derivative sensor never crept over 0.4%.

And this is why we use the derivative sensor so the fan only comes ON when is needed.

@GTunney

I’m guessing the derivative is best served for a spike in humidity instead of a gradual increase? My worry is during a shower derivative kicks in the fan, lowers humidity and then turns off however the humidity then starts to gradually increase to a point the fan should kick in again but doesn’t because the derivative is too low.

Yes, when you Have a shower you should see a spike. When finished you should see a drop spike. You then also have the option to use “Maximum Humidity” this will turn the fan ON but not OFF for when you have back to back showers. All this is explained in the FAQ Click Here.

Try it out and see it for yourself.

Blacky

[GTunney]

I shall give it a go but I don’t think it would be applicable in my scenario.

Ideally I’d like the fan to come on / off regardless of how quickly the humidity incremented so may be better off just using set values for humidity and triggering automations based on that.

[sparkydave (🇦🇺 Dave)]

@GTunney

Ideally I’d like the fan to come on / off regardless of how quickly the humidity incremented so may be better off just using set values for humidity and triggering automations based on that.

The whole point of this blueprint using derivative is to prevent the fan coming on simply because it’s a humid day. Using set values of humidity only will likely end up causing the fan to come on at odd times due to the weather. ie: in the middle of the night when you don’t want it to.

[Blacky]

FAQ – Manual Trigger

This feature allows you to manually trigger the automation, replacing the humidity derivative settings in either ‘Default - Summer Mode’ or ‘Winter Mode’ configurations. Turning it ON initiates the automation process, and turning it OFF starts the time delay. Note that auto triggers can and will override the manual trigger option if activated.

This feature can operate with or without a humidity sensor, which is particularly useful if the humidity sensor malfunctions, allowing time for repairs and reducing stress levels. It is designed with good spouse approval in mind. It can also serve as the primary trigger for the automation if you don’t have a humidity sensor and cannot create a humidity derivative sensor.

Additionally, you can customize a manual trigger by creating any template sensor you can imagine. This is a powerful feature that allows you to trigger the automation in various ways.

You can use it with a physical switch on the wall that lets you trigger the automation to turn ON the fan before a shower, aiding in humidity removal before the auto triggers take over. This can be very useful in the colder winter months when humidity levels are high or during quick, colder showers in summer where a humidity derivative sensor may not trigger the automation.

How it works.

• When you trigger the manual trigger, it will run the automation turning ON the fan, light and automation link.
• It will then wait for the manual trigger to turn OFF by either manually turning it OFF or by the safe guard or auto OFF time delay.
• Once turned OFF the automation will then proceed to the time delay in either ‘Default - Summer Mode’ or ‘Winter Mode’. It will then continue as per your settings you selected in ‘Default - Summer Mode’ or ‘Winter Mode’.

NOTE: The auto triggers can and will override the manual trigger option if activated at any point. Although this can be used as the main trigger it was designed to add value to the auto triggers.

Enjoy

Blacky

Back to FAQ: Click Here

[vicusj]

After using this great blueprint now for several weeks, I understand things around the behavior of the humidity etc all a bit better and have my setup dialed in quite well where I am quite happy with it. I experimented a lot, and tried 3 different Humidity sensors until I landed on this one, and countless mounting positions thereof in the ensuite before I was happy with it all.
I thought to share my graphs showing the relationship between humidity, the derivative, and where the fan turns on and off. Since I used these graphs, it made it much easier for myself to understand the nuts and bolts behind it all. I hope this info might help others in turn.
Thank you again Blacky for this, and all your patience with my ‘not-so-smart’ questions at the beginning

[vaclavIII]

Hello, Blacky,
I’ve successfully used your second blueprint, here’s my YAML for good measure:

alias: Ventilátor koupelna
description: ""
use_blueprint:
  path: Blackshome/bathroom-humidity-exhaust-fan.yaml
  input:
    trigger: sensor.derivacni_senzor_koupelna
    fan_switch:
      entity_id: switch.vypinac_ventilator_prepinac_1
      area_id: koupelna
    time_out: 20
    include_manual_fan_switch: enable_manual_fan_switch_auto_off
    manual_fan_switch:
      - switch.vypinac_ventilator_prepinac_1
    rising_humidity: 0.7
    include_max_humidity: maximum_humidity_enabled
    max_humidity: 80
    bypass_auto_off_delay: 20

I have a question for you about the “manual_fan_switch” function. I tried to enable it, although I didn’t have much hope that it would work. Namely: you write that the manual switch must be independent. My fan switch is a classic mechanical switch on the wall, with a wifi controller between it and the fan (only one switch is connected). Ultimately, therefore, the fan is always switched by this controller - whether it has been switched on by the mechanical switch, or by an instruction by way of wifi (and therefore automation). The situation can be clearly seen in the definitions of “fan_switch” and “manual_fan_switch” above. This explains the fact that “bypass_auto_off_delay” doesn’t work. Do you think my explanation is correct?
If so: I understand that the automation does not know if the switch was turned on by a human, or by the automation. However: Couldn’t some counter be used to track these states:

1. Switch tripping immediately preceded by an X% rise in the humidity derivative sensor value.
2. the switch trip was not preceded by a rise in the value of the humidity derivative sensor (and therefore was manually tripped - if this option is enabled)?

Thanks for the answer!

[Blacky]

@vaclavIII

Yes you can’t use the same switch that controls the fan and the manual fan switch.

Looks like you have a smart plug for the fan and a wifi switch to turn ON the smart plug. If so detach the wifi switch from the smart plug. Then use the smart plug in the automation for the fan and use the wifi switch for your manual control.

Blacky

[vaclavIII]

@vaclavIII

“bypass_auto_off_delay”

Thanks for the quick reply!
No, it is not a smart plug, it is a wifi module (controller) under the switch in the wall, the fan is also built into the wall. I don’t want to disconnect it (already because it was very difficult to put all the wires plus the controller into the switch box ).
I am attaching the controller wiring diagram to complete it:

I also found that the automation knows how the switch (controller) was turned on/off. I attach a screenshot of the history of the entity “fan bathroom switch” in HA, (I am translating from Czech):

1. Fan bathroom switch on, triggered by automation, Fan bathroom switch on, triggered by numeric state Derivative sensor bathroom
2. Fan bathroom switch, off
   (State 2 is triggered by the manual switch (and interpreted by the controller)).

Thus, it would probably be possible to build this algorithm into your automation:
If the fan is controlled by a controller that allows bypass for a mechanical switch, take into account how the fan was turned on - whether by automation or manually. In case of manual switching, enable “manual_fan_switch” and also “bypass_auto_off_delay”. I don’t know how though - I’ll leave that to an expert …