Esp32 ADC GPIO35 does not read change in resistance

ESPHome
1

A 220 kOhm pull up resistor connecting 3.3v and GPIO35.
I can see 2.69V between GPIO and Gnd.
And 1.45V when GPIO35 pulled down to Gnd with 100k resistor.

But HA log always report the same value of 1.02 V
I did try GPIO39. No difference. I’m assuming an error in YAML?

- platform: adc
    pin: GPIO35   # water sensor
    icon: mdi:water-alert
    name: "water sensor"
    id: water_sensor
    accuracy_decimals: 0

Also this code appears to be working when esp8266 in use. Tested about 8mo ago.
And sensor readings were reported in ESPhome log every second or so. With ESP32 readings populated every minu. (if the change is in newer HA, I dont see how to update sensors with shorter intervals. Sensor Component - ESPHome - Smart Home Made Simple)

2

You haven’t set attenuation so max is 1.1V, which is close to the 1.02V you are seeing.

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