I have a dallas ds18b20 in my pool and its reading 22.4 degrees.
However, my outside weather station temp is reading 19.3 degrees outside. There is no way my pool is warmer then the tempreature outside.
Is there a way to calibrate these things? This is connected to a Kinkony KC868-A8 board with a dedicated 1 wire and internal pullup already in place.
Any ideas? I’ve already tried replacing the sensor.
Thanks
Yes, the esphome docs have a quite extensive filter section including calibrate_linear for example.
Welcome, next time maybe try to search the docs and forum before posting!
I had the same issue today and found the same sollution.
The quick-fix is: Sensor Component — ESPHome
My prefered option is probably: Sensor Component — ESPHome
Could I just measure the true tempreate and set a offset?
Yes, that is the basic idea of the solutions that have been provided and are a very common approach…so…
It amazes me how so many people refuse to even make an effort to find answers to their own questions and refuse to use te Docs. They know of the docs and they know how easy it is to Google a question or use tbe search box right here but, they refuse. I dont know how to make sense of this. The only logical reason i can come up with is plain laziness or they just like being clueless. Its really qute easy and much faster to use a search box when you have a question and still people put in more effort and time to start a new thread and wait for someone else to find the answer and place it into their outstretched begger hands. God help us all if these people are procreating.
Don’t forget to use the ESPHome Add-In to edit the yaml for your ESPHome devices, and then you’ll have the INSTALL button to actually compile and upload your config updates to the actual device.
I found the docs mentioned below for filters, but was stupidly using the File Editor add-in to edit the ESPHome device’s config, and then restarting HA, and wondering why it was having zero effect.
Some of us are either quite new to this stuff, or else haven’t tweaked something in such a long time that basic concepts get forgotten.
Lucky us the getting started guide got all covered - young and old!
Without the docs I think it’s not even possible to work with esphome in a sufficient manner.
What evidence do you have that your weather station is more accurate than the DS18B20?
Probably read about the accuracy in the docs not 
I would trust my weather station as they are higher quality sensors.
However, I purchased a floating pool thermometer and placed that in the pool to measure the temp,
Turns out that the DS18B20 is about 3 degrees higher then the actualy temp reported by the floating thermometer.