Aqara has put the “T1” name on at least two, and possibly three, different temperature and humidity sensors. The original model has no marketing name at all, just a model code. The device most people mean when they say “Aqara T1 temperature sensor” is WSDCGQ12LM. And current retail listings suggest a further hardware refresh, also called T1, under a different model code entirely. If you’re trying to work out which one is screwed to your wall, or which one you’d actually be buying today, the name alone won’t tell you. This comparison sorts the generations by model code, because that’s the only thing that reliably separates them.
Three things separate the two confirmed generations. The T1 (WSDCGQ12LM) added device_temperature, power_outage_count, and OTA firmware updates through Zigbee2MQTT, none of which the original’s device page mentions. It’s documented as a Zigbee 3.0 device. And its Zigbee2MQTT page doesn’t carry the mixed-brand router warning the original’s page does. What it did not change is the core sensing: both expose temperature, humidity, pressure, and battery the same way.
The naming problem: at least three devices, one marketing name
Aqara’s newer product lines use a two-letter-plus-number naming scheme, something like “S02D” or “S04D”, that this site has covered separately. The temperature/humidity line has run into a specific version of that problem: retail listings for a current-production “Aqara T1 Temperature and Humidity Sensor” point to a model code, TH-S02D, that is different from the original T1’s WSDCGQ12LM. Whether that’s a running production change, a regional SKU difference, or a full hardware revision isn’t something a retailer listing settles.
This article treats WSDCGQ11LM and WSDCGQ12LM as the two confirmed generations, because both have official Zigbee2MQTT device pages this article was built from directly. TH-S02D is covered separately below as an open question, not as a third confirmed generation.
There’s a second naming collision worth clearing up before it causes confusion. Aqara also sells a device sometimes discussed alongside these under the “T1” family, which is actually a materially different product with a different model code: TH-S04D. That device is the Aqara Climate Sensor W100, a unit with a display, scheduling and thermostat-adjacent features, and support for pairing an external sensor. Our W100 guide covers it on its own terms.
Quick identification table
| Model code | Marketing name | Exposes beyond temp/humidity | OTA via Z2M | Battery |
|---|---|---|---|---|
| WSDCGQ11LM | Original / none | pressure, voltage |
Not listed | CR2032 |
| WSDCGQ12LM | T1 | pressure, device_temperature, power_outage_count, voltage |
Listed | CR2032 |
| TH-S02D | Also marketed as T1 | Pressure, per retailer specs — no Z2M expose list published | Unconfirmed — no Z2M device page found this run | CR2032, per retailer specs |
| TH-S04D | Climate Sensor W100 | Different product — display, scheduling, external sensor pairing | See W100 guide | See W100 guide |
The back label is the reliable check. Both confirmed generations print their full model code on the device itself, and that code is what Zigbee2MQTT and ZHA identify the device by during pairing, not the marketing name on the retail box. Aqara’s own T1 specification page can’t help you here, because it never prints a model code at all — which is a fair summary of how this line got confusing in the first place.
WSDCGQ11LM: the original
The original Aqara temperature and humidity sensor exposes battery, temperature, humidity, pressure, and voltage. It runs on a CR2032 coin cell. Its Zigbee2MQTT device page notes that Xiaomi and Aqara devices generally don’t fully comply with the Zigbee spec, and lists specific router brands the sensor can have trouble pairing or staying connected through when signal quality is weak (linkquality under 20), including Centralite, GE, Iris, Ledvance, Legrand, OSRAM, Sylvania, Securifi, and SmartThings.
That same note gives the remedy, which is worth knowing before you start replacing hardware: reset the sensor and re-pair it while it’s physically next to the coordinator, so it parents directly to the coordinator rather than through an incompatible router. This warning is carried on Aqara and Xiaomi’s first-generation device pages rather than the range as a whole, and the T1’s page doesn’t carry it. That asymmetry is the most practical reason to prefer the newer model, and it’s easy to miss because neither page advertises it.
The original’s page doesn’t mention OTA firmware update support. That’s a meaningful gap if you’re planning to run this sensor for years and want Zigbee2MQTT to be able to push a firmware fix to it later. Our WSDCGQ11LM guide has the full pairing and setup detail for this model.
WSDCGQ12LM (“T1”): what actually changed
The T1 keeps the same core sensing, temperature, humidity, and pressure, and adds three things the original’s page doesn’t have: device_temperature, power_outage_count, and listed OTA support.
device_temperature is worth being precise about, because it’s easy to misread. It’s the temperature of the sensor’s own internal chip, not a second ambient reading. Don’t treat it as a duplicate or a more accurate version of the temperature expose. power_outage_count is more straightforward: it increments each time the sensor loses and regains power, useful for spotting a battery that’s dying rather than just dead.
Aqara’s own specification page for the T1 lists the sensor as Zigbee 3.0, powered by a CR2032 cell, with a temperature range of -20 to +50°C at ±0.3°C, humidity across 0–100% RH at ±3%, and atmospheric pressure from 30 to 110 kPa at ±0.12 kPa. Those figures describe the T1 as a product line rather than a specific model code, for the reason given above, so treat them as the line’s published specification rather than proof of what’s in any particular box.
The WSDCGQ12LM’s Zigbee2MQTT page lists minimum coordinator firmware versions required for reliable pairing: CC2530/CC2531 at 20211115 or later, CC1352/CC2652 at 20211114 or later, CC2538 at 20211222 or later, and Conbee II at firmware 0x26720700 or later. If your coordinator’s firmware predates these, pairing this specific model can fail or behave unreliably even though older Aqara sensors on the same coordinator work fine. Check your adapter’s firmware version before assuming a failed pairing attempt is the sensor’s fault.
Our T1 setup guide covers WSDCGQ12LM pairing in more depth, and a second T1 walkthrough on this site goes through the Home Assistant entity side.
The known WSDCGQ12LM pressure-null bug
If your WSDCGQ12LM’s pressure reading shows up as null in Home Assistant, that’s a known, already-documented issue rather than something new to work through here. Our dedicated fix article covers the fix and the calibration steps directly.
TH-S02D: the newest refresh, and what’s genuinely unverified
Current retail listings describe a further Aqara temperature and humidity sensor sold under the T1 name, model code TH-S02D. Multiple independent listings agree on the same spec set: Zigbee 3.0, a CR2032 cell, and temperature, humidity and atmospheric pressure sensing, with accuracy figures matching Aqara’s published T1 specification. That consistency is worth something, but retailer copy is still retailer copy, and none of it is an official Aqara datasheet tied to that model code.
The bigger open question is whether Zigbee2MQTT supports it. Two separate checks of Zigbee2MQTT’s supported-devices reference failed to turn up a device page for TH-S02D. One explanation is that the model code or URL casing differs from what retailers print. The more likely one is that the device isn’t yet in Zigbee2MQTT’s supported-devices database: its same-generation sibling TH-S04D has a device page filed under exactly that retail model code, so the naming scheme itself clearly isn’t the obstacle. Several retail listings do claim Zigbee2MQTT compatibility, but vendor compatibility lists are marketing copy, not the supported-devices database, and the two disagree here.
If you buy an “Aqara T1 Temperature and Humidity Sensor” today, current production may ship you TH-S02D hardware rather than the WSDCGQ12LM covered above, and the two are not confirmed to behave identically. Before assuming this article’s WSDCGQ12LM coverage applies to what arrives in the box, check the model code printed on the device against Zigbee2MQTT’s current supported-devices list, and check ZHA’s device list separately if that’s what you run.
I think Aqara reusing the “T1” name for hardware that isn’t even confirmed to show up in Zigbee2MQTT’s device database yet is a genuinely bad call. It turns what should be a five-minute box check into exactly the kind of ambiguity this article exists to sort out.
Which one should you buy
For anyone building or extending a local-only setup with Zigbee2MQTT or ZHA, WSDCGQ12LM is the safer purchase right now, precisely because its support status is confirmed and documented. Its OTA support, extra exposes, and the absence of the first-generation router-compatibility warning are a genuine, if modest, improvement over the original. If you can find the original new or secondhand and don’t care about OTA or the outage counter, it’s fine hardware — it’s just the one with no firmware-update path and the mixed-router caveat attached.
Frequently asked questions
What’s the difference between Aqara WSDCGQ11LM and WSDCGQ12LM?
The T1 (WSDCGQ12LM) adds device_temperature (the sensor’s own chip temperature, not a second ambient reading), power_outage_count, and OTA firmware update support through Zigbee2MQTT. Both expose the same core temperature, humidity, and pressure readings.
Is the Aqara T1 temperature sensor the same as the original?
No. WSDCGQ12LM (marketed as T1) has three exposes and a firmware-update path the original WSDCGQ11LM’s Zigbee2MQTT page doesn’t list. There’s also a further, newer hardware refresh under model code TH-S02D also using the T1 name, which is a separate, currently-unverified device covered above.
Does the new Aqara T1 temperature sensor work with Zigbee2MQTT?
Unclear as of this writing. Two checks of Zigbee2MQTT’s supported-devices reference found no device page for TH-S02D, which doesn’t confirm the device is unsupported, only that its status couldn’t be verified. Check Zigbee2MQTT’s current supported-devices list against the exact model code on your unit before buying or pairing.
Why does my Aqara temperature sensor show pressure as null?
This is a known issue specific to the WSDCGQ12LM. Our dedicated fix article covers the fix and calibration steps.
Which Aqara temperature sensor should I buy in 2026?
WSDCGQ12LM, if you can confirm that’s what you’re actually getting. Its Zigbee2MQTT support, OTA path, and extra exposes are all documented. If a current “T1” listing turns out to be TH-S02D hardware, confirm support status before relying on any of this article’s WSDCGQ12LM-specific detail.
What this comparison verified
This article is built from Zigbee2MQTT’s official device reference pages for WSDCGQ11LM and WSDCGQ12LM, cross-referenced against each other and against Aqara’s own published T1 specification. No sensor was bought or paired for it.
Both confirmed generations run entirely over Zigbee through Zigbee2MQTT or ZHA, so neither depends on Aqara’s hub, app, or cloud account to keep working. Whether TH-S02D turns out to be a supported, simply-renamed T1 or something that needs its own dedicated guide is the open question worth checking before you buy one.