Mill panel heater (generation 2)
General Notes
Mill panel heaters are available in various versions. This component is specifically designed for Generation 2 panel heaters (not compatible with portable heater models). Below is a table that helps you determine which generation you have based on the Wi-Fi serial number prefix (originally linked from Mill’s support article):
Generation overview
| Wi-Fi serial starts with | Generation | Approx. year |
|---|---|---|
SKAG***** | 1 | 2016 |
SKAH***** | 2 | 2017 |
SKAI***** | 2 | 2018 |
SKAJ***** | 2 | 2019 |
SKAK***** | 2 | 2020 |
SKAL***** | 3 / 3M | 2021 |
SKAN***** | 3 / 3M | 2022 |
SKAO***** | 3 / 3M | 2023 |
MI***... | 3 / 3M | 2024 |
If you have a Generation 3 panel heater (which comes with a built-in ESP32), check out this component:
https://github.com/ssieb/esphome_components/tree/mill/components/mill_heater
To use this component with a Generation 2 panel heater, you’ll need to replace the HF-LPT120A module with an ESP8266.
HF-LPT120A desoldered
Solder the ESP8266 in place. Refer to the GPIO Pinout section for detailed instructions
GPIO Pinout
| PIN (mill board) | ESP8266 | Description |
|---|---|---|
| +3.3V | VCC | Power input (3.3V) |
| GND | GND | Ground |
| WTX | TX (GPIO1) | UART transmitter |
| WRX | RX (GPIO3) | UART receiver |
Configuration
substitutions:
devicename: "millzero_heater" #Lower case name
friendly_name: "Mill Zero heater"
esphome:
name: "${devicename}"
external_components:
source:
type: git
url: https://github.com/owangen/esphome
components: [ mill_panelheater_gen2 ]
esp8266:
board: d1_mini
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
ap:
captive_portal:
# Enable logging
logger:
baud_rate: 0 # Deactived to prevent conflict with UART, sending UART to mill controller does not work if enabled
# Enable Home Assistant API
api:
ota:
uart:
id: uart_bus
tx_pin: GPIO01
rx_pin: GPIO03
baud_rate: 9600
climate:
- platform: mill_panelheater_gen2
name: Mill heater
Credits
This component builds on the work by: