Getting two temperature values from BME280

ESPHome
1

I just started playing with the BME280, and I’ve come across something odd that I’m hoping someone can explain. I’m seeing two differing charts for temperature data when I pull up the sensor:

image

The pressure and humidity sensors are only showing one set of values as would be expected. Why am I seeing two graphs for the temp?

EDIT: So it appears to be a more recent set of values along side the historical lookback. Why would I just see this behavior here? The scale of the recent values graph also seems to be arbitrary. I pulled it up again, and now it’s only showing the past ~2-3 minutes.

Here is my esphome yaml:

esphome:
  name: bme280_wemos_01
  platform: ESP8266
  board: d1_mini

wifi:
  ssid: "<redacted>"
  password: "<redacted>"

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Bme280 Wemos 01 Fallback Hotspot"
    password: "<redacted>"

captive_portal:

# Enable logging
logger:

# Enable Home Assistant API
api:

ota:

### BME280 Setup
i2c:
  sda: 4  # D2/SDA/GPIO4 on Wemos D1 mini
  scl: 5  # D1/SCL/GPIO5 on Wemos D1 mini
  scan: True

sensor:
  - platform: bme280
    update_interval: 60s
    address: 0x76
    temperature:
      name: "BME280 Temperature"
    pressure:
      name: "BME280 Pressure"
    humidity:
      name: "BME280 Humidity"
2

I’ve seen this happen when you change units. Given time the second graph will disappear.

3

I think there is something weird about the reporting of temperatures from a bme280 via esphome to HA. I haven’t had time (or know-how) to look into it yet. I haven’t seen what @muchtall reported, but I have seen other oddities that could be related.

bme280 and esphome report the temperature in centigrade. I have my HA configured to display temperatures in fahrenheit. Most of the time, I see graphs of temperature displayed with “C” on the y-axis but with numeric values that are actually “F”.

image

But, sometimes, I will see a graph with “F” on the y-axis. And sometimes, I will see some of my sensors displayed with “C” and others with “F”. In fact, at least once, I saw both “C” and “F” graphs, where the “F” started when the “C” stopped (for a single sensor).

That’s all in the HA UI. I haven’t been too worried about fixing it up since I plan to eventually use pretty grafana stuff instead of the built-in HA graphs.

4

Here’s an example of the graphic switching from one graph to another on its own. This is from the mobile app, but the same thing happens in the web app. Notice the atticbug readings in red in the top graph suddenly go flat, which just means there are no new readings from the point where the flatness starts. The atticbug readings in light purple in the bottom graph start at that point. Beats me why. I definitely wasn’t fooling around with this stuff at 11pm when I noticed it.

image
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