esphome/heating.yaml

esphome:
  name: heating
  friendly_name: "Heating"

  # The entire setup consists of:
  #
  # - Furnace that burns oil and produces heat.
  #   It only burns when necessary, i.e. some of the
  #   controlled temperatures are below set values.
  #
  #   r/o: active (burning) / inactive (idle).
  #
  # - Boiler which keeps hot water (but can also heat it
  #   electrically, albeit turned on/off at the mains).
  #
  #   r/o: temperature.
  #
  # - Floor heating which is technically controlled
  #   via furnace control panel, but is a separate system.
  #   It also includes two radiators (which are normally off),
  #   but due to ambiguity of "heating" meaning both the process
  #   and a house-warming system, we opt in for this specific
  #   "floor heating" term.
  #
  #   r/o: flow temperature.
  #   r/o: active (flow temperature controlled) / inactive (idle).
  #   r/w: mode (instruct the flow to start heating).

  project:
    name: dasfoo.heating
    version: "2.0"

  on_boot:
    then:
      - if:
          condition:
            switch.is_off: relay_temperature_manual
          then:
            - select.set:
                id: floor_mode
                option: "auto"
          else:
            - if:
                condition:
                  switch.is_on: relay_temperature_warm
                then:
                  - select.set:
                      id: floor_mode
                      option: "off"
                else:
                  - select.set:
                      id: floor_mode
                      option: "on"

packages:
  device_base: !include templates/esp32.yaml

i2c:
  sda: GPIO21
  # Marked as SCK on the display itself for some reason,
  # thus the GPIO choice.
  scl: GPIO18

font:
- file: "fonts/DejaVuSans.ttf"
  id: font_sans
  size: 20

display:
- platform: ssd1306_i2c
  model: "SSD1306 128x32"
  id: oled_display
  lambda: |-
    it.printf(
      4, 6,
      id(font_sans),
      "%.2f C",
      id(boiler_temperature).state);

    if (id(furnace_burning).state) {
      it.filled_circle(112, 16, 12);
    } else {
      it.circle(112, 16, 12);
    }

dallas:
- pin: GPIO27

sensor:
- platform: dallas
  address: 0x133c2cf648f40728
  id: boiler_temperature
  name: "Boiler temperature"
  filters:
  - offset: 0.5

- platform: dallas
  address: 0x6a0316643959ff28
  id: floor_temperature
  name: "Floor temperature"

- platform: adc
  pin: GPIO32
  update_interval: 1s
  id: furnace_burning_led_brightness
  attenuation: auto
  # Make voltage value available in UI for debugging and history.
  name: "Furnace burning - LED brightness"
  entity_category: diagnostic
  disabled_by_default: true

- platform: adc
  pin: GPIO33
  update_interval: 1s
  id: floor_active_led_brightness
  attenuation: auto
  # Make voltage value available in UI for debugging and history.
  name: "Floor active - LED brightness"
  entity_category: diagnostic
  disabled_by_default: true

binary_sensor:
- platform: analog_threshold
  id: furnace_burning
  name: "Furnace burning"
  sensor_id: furnace_burning_led_brightness
  # The reading (V) gets lower as brightness increases. Keep the threshold
  # low (close to LED reading) to avoid triggering with a lamp or natural light.
  threshold: 2.2 # LED on = 1.93V, flashlight on = 2.5V.
  filters:
  - invert:

- platform: analog_threshold
  id: heating_enabled
  name: "Floor active"
  sensor_id: floor_active_led_brightness
  # This sensor is more exposed to external light due to construction.
  threshold: 1.9 # LED on = 1.76V, flashlight on = 2.1V.
  filters:
  - invert:

switch:
- platform: gpio
  pin: GPIO25
  id: relay_temperature_manual
  inverted: true
  restore_mode: RESTORE_DEFAULT_OFF

- platform: gpio
  pin: GPIO26
  id: relay_temperature_warm
  inverted: true
  restore_mode: RESTORE_DEFAULT_OFF

select:
- platform: template
  name: "Floor mode"
  id: floor_mode
  options:
  - "on"
  - "off"
  - "auto"
  optimistic: true
  set_action:
    lambda: |-
      if (x == "auto") {
        id(relay_temperature_manual).turn_off();
      } else {
        if (x == "off") {
          id(relay_temperature_warm).turn_on();
        } else {
          id(relay_temperature_warm).turn_off();
        }
        id(relay_temperature_manual).turn_on();
      }