I’m brainstorming ways of finding out when cooking occurs and the amount of steam/smoke that needs to be extracted with my extractor hood. The extractor hood is a ceiling mounted unit that can be controlled with a remote control that I’ll spoof with a Broadlink RM4, it has four intensity levels. So far I’ve thought about:
Measuring the power consumtion of the induction cooktop. That would require some pretty serious hardware because the cooktop is 11.1kW / 3 Phase. Probably something like the Shelly 3EM. A solution like that is available from many companies making extractor hoods like: Thermex Top Link® - YouTube But they don’t seem very smart at all, working basically as a binary switch and would probably just become annoying and overridden most of the time.
Alternatively I could measure the current on a single phase with a Shelly EM and use that information to turn on the extractor hood, this option would be much cheaper.
Measure the air quality next to the intake of the extractor hood, to measure the “intensity” of cooking. more pollution → higher intensity level. Something like the Tuya Smart Air Quality Sensor seems like a good but cheap option and gives a bunch of options. Humidity is probably always a good bet, but when searing a steak a better indicator of “intensity” would might be PM2.5 or CO2.
The best solution is probably some sort of hybrid, turn on extractor fan when the cooktop gets powered on, measure the air quality to evaluate the amount of pollution happening and adjust the extraction level accordingly, turn off when air quality is back to normal.
That’s my rant, I’d love to hear anyone’s thoughts on the subject!
I think humidity will be enough.
There is some humidity in everything and when you heat it up it will release some humidity.
So having a humidity sensor inside the hood should be enough to trigger.
Air quality sensor, do the react on just boiling water?
That would make for a much sleeker installation, Temperature/Humidity sensors can be quite small in comparison.
It’ll also be interesting to tune the software side, turning on the extraction would pull more air=humidity into the sensor, increasing the perceived need for extraction. That might be a good thing though, when it reaches equilibrium it might be set optimally.
I have a Sonoff TH10 that is measuring the temperature above a radiator, I’ll try it out with that. My only concern is the distance between cooktop and extraction hood, it’s 1.5 meters between them, so it’ll probably take a while for the humidity to hit the sensor.
Nah…
If you boil water or if you put some butter in a pan then it rises immediately.
I think the sensor will be the slower part of the detection not the actual humidity
My use case is to just monitor when the stove is on, with primary use to notify is stove is left on. So I use temperature delta between two Bluetooth BLE sensors, one in stove hood, one in kitchen occupied space. So this does not address smoke sensing and would trigger on the water boiling case. All that said, I have found this to be a very reliable setup. If nothing, it might offer additional data to a primary smoke solution, at a low cost. The sensor I use in the stove hood is a Govee H5074, amazon link below. It is pretty robust, no issue with temperatures up to 140’s fahrenheit. Second link is a chart showing the temperature reading rates of some BLE sensors. Good hunting!
