Everyone loves the IBS-TH2. It’s an excellent, super accurate thermometer. It’s IPXX so it can be used in freezers and other humid environments. It’s compatible with HA.
Except, it has huge thermal inertia. It can take up to an hour for it to converge to the ambient temperature of the place it’s located in. I’ve compared it with a K-type thermocouple (near instant) and — while accurate — it leaves much to be desired. Aqara and Xiaomi Mi thermometers are much faster.
I found a fix.
- Open the back and remove the batteries.
- Crack open its case carefully,
- Toss the front shell.
- Snap off the post that supports the thermometer sensor.
- Remove the rubber seal that sits atop the thermometer sensor.
- Keep the rear shell — reinsert the battery terminals in it, and place the batteries again. This should suffice to keep the thermometer in place.
- Close the back lid with its screw.
With this mod, the thermal inertia of the device becomes smaller than all other indoor thermometers I’ve tested, reaching the area temperature to a tenth of a degree three times faster (18 minutes instead of an hour) in my tests.
Of course, it still won’t be anywhere near as fast as a K-type thermocouple, and you can no longer use the device as-is in high moisture applications. But you can safely use this thermometer outdoors — much easier to power than an ESP + BME280 combo, and more budget-friendly than a professional weather station — if you place it into my free-to-print open source Stevenson screen:
I haven’t tried the mod in the version of the IBS-TH2 that has a hygrometer, but if you do have one, and you plan to try this mod, please post pictures downthread.
That’s it! I just wanted to report my findings. I hope someone else finds this useful.