I have been using Xiaomi Mi and now Aqara sensors for Bathroom fan control for several years now with great success. From my experience its not the sensor reporting rate that makes the biggest difference. It’s how you decide when to turn on and off your fans. Back when I used SmartThings I had a Webcore piston that took a humidity reading every minute and if the jump between readings was more than 5% it set a baseline (previous reading) and turn on the fan. Then when the humidity reduced to the baseline the fan would switch off. My HA scripting is not yet to the point for me to replicate this in HA so I am currently using the Generic Hygrostat in HACS to do the same job. Although not quite as good as my Webcore Piston, it does the job until I can successfully implement my code in a script.
I currently have both Xiaomi Mi and Aqara humidity sensors connected via Conbee II and ZHA. Reliability is excellent and the battery life of the sensors is amazing.
I turned onthe shower at 10:55. It wasn’t until 5 and a half minutes later that there’s a sensor report showing the humidity increase. That’s not… useful.
Interesting to see in that graph is that most reports seem to be either greater than a 5% humidity change or greater than 5 minute since last report, but not all off them.
From the Z-Wave JS database I can see that humidity reporting threshold (parameter 3) is supported. What do you have parameter 3 set to? From the graph it looks like 5%. The default is 10% to save battery, but that’s not useful at all for a bathroom. 1% would be a better setting but it would eat those expensive batteries.
I think at the end of the day you would be better off going with an Aqara sensor though.
(See the 10 min graph; shower started between 10:33 & 10:34pm.)
This is from the sonoff SNZB-02… $8.5 USD directly from sonoff / itead at the moment.
Have not changed any parameter on the sensor - there’s no need to my use case.
Can’t say about long term reliability since I have only got it a few days ago. But at least this is a reference point on the fast response & price point.
Also, somewhere on YouTube someone must have done some side by side comparison on various sensors.
Have you decided which sensor (or sensors) you would go with? Or have you addressed the issue via some parameter changes on your Zooz 4-in-1?
I’ll check out the SNZB-02 — seems like it’s working for you, and easy to see for myself at that price. Zooz tech support tells me this device prioritizes motion, and that their dedicated temperature / humidity sensor would be better — but it’s $40.
Interesting you say Aqara sensors report regularly for you. I have the WSDCGQ11LM and it is showing the same problem of major lag before updating that the OP is experiencing with the Zooz.
I came here looking for something faster, as 11 minutes to react from switching the shower on is not acceptable to me.
@mattdm Did you try the Sonoff and did it resolve the problem for you?
If anyone has any ideas, I’d also be interested in hearing why my Aqara sensor is taking so long to react if others are not experiencing this. Ideally I would rather not replace it as I bought three of these for activating extractor fans based on humidity. I am using it with Zigbee2MQTT and a Conbee II stick. From what I have read, these particular Aqara sensors do not support changing the reporting intervals.
Yeah, that wouldn’t work for me either. All I can say mine perform well in 4 bathrooms. Fan and lights come up within one, maybe up to two minutes of the water running hot, usually about the time I’m stepping in.
From my personal experience: positioning is everything. Experiment with different positions for the humidity sensor. Too much or too little airflow where it resides makes a huge difference.
I don’t think so. My experience with ZigBee sensor, I had the feeling they (force throttle) to conserve battery. Maybe they don’t even take measurements for a period of time so obviously they lack/loose measurements which ultimately leads to low response times.
I ditched all my ZigBee humidity sensor for cheaper Xiaomi BLE ones with display which (contrary to the ZigBee ones) react fast and can even be customized (default broadcasts every 2.5 seconds I think).
The BLE hygrometers are located on the exact same spot like the formerly owned ZigBee ones but react almost instantly!
There is some combination of measurement delta vs frequency. I went back and looked at the past several days, during rapid changes after starting the shower, I’ll see readings every 15-60 seconds. I don’t see small delta’s that frequently, ie a 1% change probably wouldn’t update in under a minute, but a 10% change would. There is gray area in between, I’ve never tried to figure out the exact algorithm, but so far they fit my needs.
I am pretty sure it’s nothing to do with positioning. I’ve been trying to upload the history graph, but for some reason it keeps giving an error. There is no reaction for about 11 minutes and then it jumps by a good few percent, so it’s like the reporting rate is being throttled to once every 5 minutes or something.
Also using Aqara Temp/Humidity sensors in all areas of my house, bought at different times over the past 2-3 years. I also have some original Xiaomi Mia ones as well. The bathroom ones react fast enough, maybe a take a minute or so. I am using a Conbee II and ZHA.
If I just look at a graph it only shows change every 5 minutes but off I tune the reporting down to a smaller period when I know the shower was on, I can see a faster rate of change.
My understanding was that the sensors report on a fixed time interval unless there is a significant change and then report immediately. Not sure what a significant change is, but it seems good enough for my use.
If the temperature, humidity and atmospheric pressure vary only a bit, data will be reported once an hour.
If the temperature variation exceeds 0.5℃ (1℉), the humidity variation exceeds 6% and the atmospheric pressure is no less than 25hPa, data will be reported instantly.
From what I have read, this is not changeable in Zigbee2MQTT reporting (seems to be hardcoded into the sensors) and it does seem to correlate roughly with what I am seeing. It appears to be only updating when the temperature has increased by 0.5, which seems to be detected quicker than the humidity increase, which is then getting triggered by a +6% increase. This is probably fine for most use cases, but not for switching an extractor fan on when showering, at least not for how it’s performing for me anyway. Still not sure how others are seeing faster responses, unless some batches of sensors have different reporting limits set.
It looks like the Sonoff SNZB-02 does support configuring the reporting interval, so I think I am going to order one and give it a go. Short of that, it might be a case of setting up some Bluetooth Proxies and going the Bluetooth sensor route as suggested by @indeeed.
@mattdm I would be very interested to know how you got on with the Sonoff.
Those parameters still don’t tell the whole story. I routinely get changes of less than 6% in something closer to real time. Maybe not instantly, but certainly not hourly.
Strange we are seeing such a discrepency in reporting/response with apparently the same sensors. I checked and my firmware matches yours.
I tried another Aqara sensor (in case the one I was using was faulty) and it’s behaving exactly the same. I’ve ordered a Sonoff and will report back on whether there is any improvement with it.
