HiLetgo 2pcs DHT22/AM2302 Digital Temperature and Humidity Sensor Module Temperature Humidity Monitor Sensor Replace SHT11 SHT15 for Arduino Electronic Practice DIY

These work great. Only 3 wire saves a conductor. Easy to use, nice that they come with short cables to use during development. Arduino library makes interfacing easy.

I'm a little new to the world of ESP and this was my first attempt to add something to my Atom Lites. But boy was it easy. I connected 3 Dupont wires from this to 5V, GND, and a GPIO pin on the Atom and was off to the races. Just added a handful of lines of YAML to ESPHome on Home Assistant and the sensors were created. Literally a 5 minute thing, plug and play - no resistor. In terms of accuracy, I have this and a Govee BLE an inch apart on my desk for a few hours and the Govee says 70.9 F and this is putting out 70.9 F. Govee humidity is 38% and this is 39%. If they aren't accurate, well they are identically inaccurate - and I think that is unlikely. Certainly you can find alternatives for a few dollars less, but I wanted no fussing and this delivered.

I've bought two sets of these so far, they're reasonably consistent in regards to the reported values. And they're comparable to DHT22's sold by others. Which is good because I use a number of these throughout my home. And the readings are consistent between individual sensors and the reported values are also consistent within a reasonable range. The supply voltage is crucial to these sensors regardless of the vendor. The part (DHT22/AM2302 w/o a board) is spec'd 3.2 or 3.3 to 5 volts. If you are running one of these from a ESP-12E or other MCU with an integrated 3.3v regulator then chances are it will work without issue. And at 5v they'll work without any problems. However, I'm running them from an ESP-01 and external LM1117 regulator board where the regulator is an SMT part. There I've found that the regulators can be off and supply a voltage as low as 3.0 volts. NOTE: The ESP-01 supply voltage is spec'd at 2.7 to 3.6v or 3.7v, depending on the information source. When the supply voltage is at 3.2 or lower the device will not report correctly. Depending on the exact supply voltage the device may either not work at all or intermittently report "NaN" when using the Arduino library. The solution I found for my devices (ESP-01 + LM1117 SMT) was to supply the DHT22 with 5v and use a BSS138 circuit to handle the 3.3v VS 5v sides of the circuit. This has worked extremely well and a "test" device has been running 24/7 with the modified circuit for 3 months without any reading errors. Before that the error rate was about 20 to 50%. Bottom line, this is an excellent sensor for most hobbyist applications. It has the required resistor & capacitor already on-board and the connecting wires are a nice addition. However, for my application I would have preferred male/female wires instead of female/female. I will purchase these again the next time I need some.

I ended up buying two different temp / humidity sensors on Amazon. The first one, a sensor sold by WWZMDiB on Amazon (the one on the left in the picture) worked out fine for my ESP 8266 project, but the humidity readings seemed to be about 5% off compared to my "Airthings" radon/humidity/temp readings. The HiLetgo DHT22 in contrast gave me readings that exactly matched my "Airthings" and another table top temp / humidity device. I don't have any way to prove which one was right other than thinking if 3 devices agree, I have a better chance of being close to the actual value. You can see in the picture that the HiLetgo is just neater. The plastic enclosure around the sensor just looks crisp on the HiLetgo, but not quite as good on the other. Solder joints were just a tad cleaner on the HiLetgo. The HiLetgo was about twice the price, but I think it is worth paying a little more for a sensor that I am more confident in using. Both units came with hookup wire which made connecting them to the ESP 8266 a breeze. Both claim the same specs on accuracy. The "WWZMDiB" was cheaper and performed okay, just seemed to be a step down from the HiLetgo.

Picture shows a Grafana plot of three of them running within a few feet of each other over the course of about 50 minutes. I don't know how good the absolute accuracy is, but they seem very consistent. Dewpoint is calculated from humidity and temperature according to the Magnus formula. The sensor appears to be an AM2302. BE VERY CAREFUL swapping devices from different manufacturers. If you hold them with the sensor packages facing you and the pins down, some are + OUT - (or VCC OUT GND) and some are - OUT + (or GND OUT VCC).

I have been using these with ESP32 boards for a home automation project and they work fine.

Work will with my Raspberry pi 4

Bought a two pack and only one will work Upon looking at the sensors I can see that the bottom sensor (the one that doesn’t work) has a diode installed backwards when comparing it to the functioning sensor I haven’t figure out how to contact their customer service to see if they would offer a replacement so I’m leaving this review in hopes that they will reach out, if not this review is to warn future buyers to pick a different brand