How to rectify on board temperature sensor accuracy

[BigBobbas]

I'm trying to see if there is a consistent temperature difference on the majority of devices. I find that if I sit another temp sensor near the box I am getting a higher reading of around 4 degrees c. are you also seeing the same scenario?

[youkorr]

Is it possible to remove or replace it with another sensor?

[BigBobbas]

an offset can be applied in the config to make the reading correct, because of its location it reads high as it is getting heat from the rest of the device. The reason for the poll is to see if this is the same for others and if so to find out if the difference is consistent with other users.

[geddyleefan]

I have a dedicated thermometer/humidity sensor, an Adafruit Funhouse, and the S3 all right next to each other, none show the same temperature :) The Funhouse has lights on it, so that affects the reading on it, I've tried to compensate for that, but it's inconsistent. The S3 seems to consistently read about two degrees over the dedicated temp sensor, so at least that one is fixable.

[BigBobbas]

I have a dedicated thermometer/humidity sensor, an Adafruit Funhouse, and the S3 all right next to each other, none show the same temperature :) The Funhouse has lights on it, so that affects the reading on it, I've tried to compensate for that, but it's inconsistent. The S3 seems to consistently read about two degrees over the dedicated temp sensor, so at least that one is fixable.

Thanks for your feedback. To rectify this you can edit the sensor config to :

sensor:
  - platform: aht10 
    i2c_id: bus_b
    variant: AHT20
    temperature:
    filters:
      offset: -2
    name: "Temperature"
    id: s3temp
    humidity:
      name: "Humidity"
    update_interval: 60s

I hope that helps 👍

[BigBobbas]

Hi to all of me it depends sometimes as the box is with a battery I can have with 100% battery a difference of 4 degrees then at 50% battery the difference is 1 degree???

in this case it would be difficult as the difference is varied... so setting a static offset wouldn't really be effective. It may be possible to do a dynamic offset based on the battery level, however this isn't something that I currently have time to work on, with everything else to do too!

[youkorr]

thank you very much for your work I will start applying it

[geddyleefan]

I have a dedicated thermometer/humidity sensor, an Adafruit Funhouse, and the S3 all right next to each other, none show the same temperature :) The Funhouse has lights on it, so that affects the reading on it, I've tried to compensate for that, but it's inconsistent. The S3 seems to consistently read about two degrees over the dedicated temp sensor, so at least that one is fixable.

Thanks for your feedback. To rectify this you can edit the sensor config to :

sensor:
  - platform: aht10 
    i2c_id: bus_b
    variant: AHT20
    temperature:
    filters:
      offset: -2
    name: "Temperature"
    id: s3temp
    humidity:
      name: "Humidity"
    update_interval: 60s

I hope that helps 👍

I'm just going to tack a -2 onto my F conversion :)

[mikey60]

The temperature difference slightly increases with the battery switch on because of the battery LED that is nearby.

[Lin4fun]

Testing completed!

Here a code example to make the offset adjustable through the device config under esphome devices. Now corrected and tested, see below.
In devices - esphome - your esp3box3 you can adjust the temperature offsett. Initial is set to -2 C, you can adjust from -5 to +5. You can read the raw meassured temperatur as well the adjusted one from diagnostic part under the device. Shown on display is the temperature which is corrected through the offset temperature.

Just paste misding number and globals. Replace ath part from sensor:

i2c:

• id: bus_a
  sda: 21
  scl: 22
  scan: true
• id: bus_b
  sda: 18
  scl: 19
  scan: true

globals:

• id: temp_offset
  type: float
  restore_value: yes
  initial_value: '-2.0'

number:

• platform: template
  name: "Temperature Offset"
  id: temp_offset_number
  optimistic: true
  min_value: -5.0
  max_value: 5.0
  step: 0.1
  initial_value: -2.0
  set_action:
  • globals.set:
    id: temp_offset
    value: !lambda 'return x;'

sensor:

• platform: aht10
  i2c_id: bus_b
  variant: AHT20
  temperature:
  name: "Raw Temperature"
  id: raw_temp
  humidity:
  name: "Humidity"
  update_interval: 60s

• platform: template
  name: "Adjusted Temperature"
  id: s3temp
  unit_of_measurement: "°C"
  lambda: |-
  return id(raw_temp).state + id(temp_offset);
  update_interval: 60s
  accuracy_decimals: 1

[PCServices2]

I'm getting an error when compiling the updated code.

INFO ESPHome 2024.8.1
INFO Reading configuration /config/esphome/lr-box-3.yaml...
ERROR Error while reading config: Invalid YAML syntax:

while scanning a simple key
in "/config/esphome/lr-box-3.yaml", line 372, column 5
could not find expected ':'
in "/config/esphome/lr-box-3.yaml", line 373, column 5

The section of code it is referring to is:

number:

• platform: template
  name: "Temperature Offset"
  id: temp_offset_number
  optimistic: true
  min_value: -5.0
  max_value: 5.0
  step: 0.1
  initial_value: -4.5
  set_action:
  • globals.set:
    id: temp_offset
    value: !lambda 'return x;'

sensor:

• platform: aht10
  i2c_id: bus_b
  variant: AHT20
  temperature:
  name: "Raw Temperature"
  id: s3temp
  humidity:
  name: "Humidity"
  update_interval: 60s

• platform: template
  name: "Adjusted Temperature"
  id: s3temp
  unit_of_measurement: "°C"
  lambda: |-
  return id(raw_temp).state + id(temp_offset);
  update_interval: 60s
  accuracy_decimals: 1

The 3rd line from the end is line 373

I'm not a programmer and don't know where the colon (:) should be.

Any help would be very much appreciated

Thank You

[BigBobbas]

try putting 2 spaces before this line
return id(raw_temp).state + id(temp_offset);
as this needs to be indented

[PCServices2]

try putting 2 spaces before this line return id(raw_temp).state + id(temp_offset); as this needs to be indented

Thank you. I tried that but got some other errors. Possible that I missed something elsewhere in the changes I made.

I reverted the changes and used the geddyleefan code (above), which worked for my needs.

[PCServices2]

FWIW, compared to my other sensors, that are in the same room, the Box 3 reads about 4.5C above the ambient temperature.