Change in humidity to trigger exhaust fan

[adamthp]

A while back I saw a member talk about a program they use to trigger an exhaust fan in a bathroom. Instead of using a set humidity point, it sounded like they were using change of humidity over a short time period as their trigger. This alleviated the potential for different humidities throughout the year triggering the program. 

On to my question.... does anyone have an example of this type of program they wouldn't mind sharing? I'd like to use the same change of humidity as a trigger, but can't put my finger on how to do it. 

Thanks in advance! 

[simplextech]

9 minutes ago, adamthp said:

A while back I saw a member talk about a program they use to trigger an exhaust fan in a bathroom. Instead of using a set humidity point, it sounded like they were using change of humidity over a short time period as their trigger. This alleviated the potential for different humidities throughout the year triggering the program. 

On to my question.... does anyone have an example of this type of program they wouldn't mind sharing? I'd like to use the same change of humidity as a trigger, but can't put my finger on how to do it. 

Thanks in advance! 

I use Temp/Humidity sensors that connect to my Ambient Weather station.  I have one of the sensors in the bathroom and a very simple program:

Bathroom.Humidity - [ID 0020][Parent 0001]

If
        'Ambient Weather / WS-1401-Addon' Sensor 1 Humidity >= 75%
 
Then
        Set 'Bathroom / sw.Bathroom.Fan' On
 
Else
   - No Actions - (To add one, press 'Action')

I have other programs that check if the fan is on and for how long and then turn it off.  But just a very simple humidity check mainly used if someone is in the shower without the fan on...

[palayman]

3 minutes ago, simplextech said:

I use Temp/Humidity sensors that connect to my Ambient Weather station.

I was concerned about latency.  Do they react fairly quickly to humidity changes.  I had thought about using some wireless tags for this.

Paul

[simplextech]

4 minutes ago, palayman said:

I was concerned about latency.  Do they react fairly quickly to humidity changes.  I had thought about using some wireless tags for this.

Paul

The sensors update the Ambient Weather system every 60 seconds and the data feed to the nodeserver is real-time as changes happen.

Wireless Tags are also great and I've been thinking about buying some too

 

[adamthp]

@simplextech

This just got me to thinking that I have plenty of other humidity sensors in the house. (either z-wave multi sensors, or nest thermostats) I can just compare the humidity in the bathroom to one of the other sensors in the house, and if the difference is greater than 20% switch on the fan. 

I actually have a CAO sensor in the bathroom currently that just triggers the fan once a certain threshold is hit. I'd like to get away from the cloud dependency for this, so I have an Aeotec multi 6 in the bathroom I can use to compare to another one in the house.

 

Thanks for the inspiration. 

[Bumbershoot]

The wireless tags respond quickly.  Here's a link to a 24 hour snapshot: https://my.wirelesstag.net/eth/tempStats.html?e4f7284b-8a11-4ce3-a474-e52d4c30a584&Master Bath Motion Detector&F

2 minutes ago, adamthp said:

@simplextech

this just got me to thinking that I have plenty of other humidity sensors in the house. (either z-wave multi sensors, or nest thermostats) I can just compare the humidity in the bathroom to one of the other sensors in the house, and if the difference is greater than 20% switch on the fan. 

 

I do this very thing.  The Nest only reports out humidity data in 5% increments, so I use a Z-Wave multisensor instead.

[adamthp]

Just now, Bumbershoot said:

The wireless tags respond quickly.  Here's a link to a 24 hour snapshot: https://my.wirelesstag.net/eth/tempStats.html?e4f7284b-8a11-4ce3-a474-e52d4c30a584&Master Bath Motion Detector&F

I do this very thing.  The Nest only reports out humidity data in 5% increments, so I use a Z-Wave multisensor instead.

Would you mind sharing your program? I'm working on this right now and realized I'm not sure how to calculate the difference the difference to trigger. I got as far as creating integer variables to represent the two humidity levels... but where do you go from there?

Thanks!

[Bumbershoot]

4 minutes ago, adamthp said:

Would you mind sharing your program? I'm working on this right now and realized I'm not sure how to calculate the difference the difference to trigger. I got as far as creating integer variables to represent the two humidity levels... but where do you go from there?

Thanks!

Okay, these are a bit cumbersome.  I turn on the fan only when the Master Bath humidity spikes 7% over the humidity on the other side of the house (I use variables to do this, and $s.ZW_008Humidity comes from a mulitsensor in another room).  I shut if off when the humidity drops to only 5% over.

I have a 2% hysteresis between the stop and start values for my fan so it doesn't toggle on/off incessantly (I'm not sure that's the best thing for a fan motor).  These programs run with every humidity change between the hours specified.

This sets the threshold at which the fan turns on:

MastBathTargetHumidityHIGH - [ID 00B2][Parent 007E]

If
        $s.ZW_008Humidity > 1
 
Then
        $i.HouseHumidityPlus7  = $s.ZW_008Humidity
        $i.HouseHumidityPlus7 += 7
 
Else
   - No Actions - (To add one, press 'Action')

This sets the threshold at which the fan shuts off:

MastBathTargetHumidityLOW - [ID 00B3][Parent 007E]

If
        $s.ZW_008Humidity > 1
 
Then
        $i.HouseHumidityPlus5  = $s.ZW_008Humidity
        $i.HouseHumidityPlus5 += 5
 
Else
   - No Actions - (To add one, press 'Action')

This starts the fan upon high humidity (I check to see if the Nest is running my HVAC fan, as I have a whole home humidifier, and I don't run the fan if I'm trying to drive humidity up):

MasterBathFanHumidityON - [ID 00B0][Parent 007E]

If
        From     7:00:00AM
        To       6:00:00PM (same day)
    And $s.MasterBathHumidity >= $i.HouseHumidityPlus7
    And $s.NestHeatCool is 0
// The variable $.s.NestHeatCool is used to see if my HVAC is adjusting the home environment already.
 
Then
        Run Program 'MastBathFan' (Then Path)
 
Else
   - No Actions - (To add one, press 'Action')
 

Here's the program that stops the fan:

MasterBathFanHumidityOFF - [ID 00B4][Parent 007E]

If
        $s.MasterBathHumidity <= $i.HouseHumidityPlus5
 
Then
        Run Program 'MastBathFan' (Else Path)
 
Else
   - No Actions - (To add one, press 'Action')
 

And here's the simple program that starts/stops the fan:

MastBathFan - [ID 0016][Parent 007E]

If
   - No Conditions - (To add one, press 'Schedule' or 'Condition')
 
Then
        Set 'Devices / dirMasterBath / sloMasterBathFan' On
 
Else
        Set 'Devices / dirMasterBath / sloMasterBathFan' Off
 

 

[palayman]

1 hour ago, simplextech said:

The sensors update the Ambient Weather system every 60 seconds

I wasn't so concerned about the system latency, rather the humidity detector itself.  I have moved a tag into our MBR bath and will monitor for a few weeks.

Thanks,

Paul

[adamthp]

@Bumbershoot

Thanks for this. I was getting close, but your program is a little more elegant and detailed than mine. I really appreciate you sharing. What reporting interval do you have your z-wave sensor set to? 

Thanks

[Bumbershoot]

29 minutes ago, adamthp said:

@Bumbershoot

Thanks for this. I was getting close, but your program is a little more elegant and detailed than mine. I really appreciate you sharing. What reporting interval do you have your z-wave sensor set to? 

Thanks

Good question, but I don't recall as I set it up years ago.  Whatever it is though, it's sufficient, as the humidity in the house changes slowly with the exception of the bathrooms and laundry room. 

FWIW, the CAO Wireless tags work well enough in the bathroom.  My better half isn't impressed with "barnacles" (also known as multi/motion sensors, both Insteon and Z-Wave) that get stuck on the walls around here, so I use a tag that's unobtrusive/easy to hide.

EDIT: Here's a screenshot of the humidity that the CAO Wireless tag reports when a shower is taken in the master bathroom:

 

[Bumbershoot]

@adamthp I just realized that my use of INTEGER variables in these programs may not work for you if humidity control is critical.  You might want to use STATE variables instead, so that your programs run if any one of the variables change -- you may get more beneficial activity out of your fan if you do.  In my case, it's not a big deal, but if I were writing these programs for general use, I'd use STATE variables.

[larryllix]

There no time scale indicated to make your point clear.

 

I would think my shower would be done by the time my Tags reported high humidity if I started at the beginning of a 15 minute update period.

 

Sent from my SM-G930W8 using Tapatalk

 

 

 

 

[Bumbershoot]

27 minutes ago, larryllix said:

There no time scale indicated to make your point clear.

 

I would think my shower would be done by the time my Tags reported high humidity if I started at the beginning of a 15 minute update period.

 

Sent from my SM-G930W8 using Tapatalk

 

 

 

 

I have my tag update frequently during the hours when the programs might run, but that's handled from the Wireless Tag website, so it doesn't show up in these programs.  It would certainly be easy enough to have the ISY run a query against the tag periodically if the Tag Manager nodeserver is used -- there are just too many ways to to do things, sometimes... ?

[palayman]

13 minutes ago, Bumbershoot said:

I have my tag update frequently during the hours when the programs might run, but that's handled from the Wireless Tag website, so it doesn't show up in these programs.  It would certainly be easy enough to have the ISY run a query against the tag periodically if the Tag Manager nodeserver is used -- there are just too many ways to to do things, sometimes... ?

@BumbershootI really like what you have done.  I plan to move a couple of my wireless tags this weekend.

I guess you could considered adding a wireless methane sensor as well ? There is a Z-Wave one around https://products.z-wavealliance.org/products/2995

[Bumbershoot]

1 hour ago, palayman said:

@BumbershootI really like what you have done.  I plan to move a couple of my wireless tags this weekend.

I guess you could considered adding a wireless methane sensor as well ? There is a Z-Wave one around https://products.z-wavealliance.org/products/2995

Ha, I hadn't thought of that.  I do have a separate fan in the WC that I could automate, but I'd probably do unnecessary damage to my WAF score -- she still has her sense of humor about home automation.  I wouldn't mind finding a way to prank the guests bathroom, especially when my sister-in-law visits (she thinks home automation is silly).  Maybe something obnoxious with the vanity lights... ?

[simplextech]

12 minutes ago, Bumbershoot said:

I wouldn't mind finding a way to prank the guests bathroom, especially when my sister-in-law visits (she thinks home automation is silly).  Maybe something obnoxious with the vanity lights... ?

Opposite lighting rule?  Motion turns off the lights instead of on?  So enter the room and lights go off... leave and lights turn on.... ?

 

[Bumbershoot]

28 minutes ago, simplextech said:

Opposite lighting rule?  Motion turns off the lights instead of on?  So enter the room and lights go off... leave and lights turn on.... ?

 

That would work, but I'd immediately get yelled at.  I was thinking of lighting that would make her face look grey, so she would put on lots of bright makeup...  Probably get me yelled at, too...

[simplextech]

2 hours ago, Bumbershoot said:

That would work, but I'd immediately get yelled at.  I was thinking of lighting that would make her face look grey, so she would put on lots of bright makeup...  Probably get me yelled at, too...

I thought the point WAS to get yelled at?

Put some LIFX bulbs (Or other smart color bulbs) in there and change their hue to make everything appear like soft white but with a nice orange tinge in the light and her makeup will come out looking like a spray tan!

[Bumbershoot]

11 hours ago, simplextech said:

I thought the point WAS to get yelled at?

It is, but not before a laugh!

11 hours ago, simplextech said:

...come out looking like a spray tan!

Yeah, now we're talking...  I like HA to be subtle...