Temperature data logging (Central heating and stuff)

I bought 10 IoT temperature & humidity sensors for £25 on aliexpress and hooked them into my Google Home setup which I then connected to a setup of Home Assistant in a docker container on my server.

All the graphs you could ever want, and you can d/l data for your own spreadsheets or whatever.

Been running for 3 weeks now, and already there are some interesting findings. One room mysteriously seems to stay warmer than the house as a whole. No idea why.

I think it really comes down to form factor.

'Room' temperature sensors (for mounting on your wall) that use zigbee/bluetooth/wifi are ten a penny.

'Probe' sensors (with a ~5mm metal bar you can shove in places) are a bit rarer, but do exist.

'Bead' sensors (with a tiny thermistor or thermocouple bead you can eg tape to a pipe) are a bit harder.

There are things like this:

I think these are typically set up for the Tuya app out of the box, which will likely provide some logging. You can then set them up to talk to a larger system like Apple/Google/Home Assistant if you want.

Have you swapped the sensors around to check for sensor offsets? I get the impression the cheap sensors aren't super accurate.

Theo

I haven't ... I may do.

Accuracy is really in the eye of the beholder. I can live with a +/- 0.5C margin of error at c. £2 a pop :)