I’d like to invite everyone to vote/comment on this Home Assistant feature request:
Wouldnt it make sense to build hourly averages and calculate an hourly COP. I dont think minute COPs make any sense. COP granularity per day should be good enough. Hourly is already quite nerdy 
I do only calculate daily, monthly and yearly COP values. The diagram was just a visualization of the issue.
@brambo123 created a new branch, in which the energy is calculated on the ESP with a higher resolution now: GitHub - brambo123/esphome-sensostar at sub-integer-energy
Thus, the issue is solved for me. 
The second batch of PCBs arrived today. Shipping will begin after the New Year.
I would like to wish you all a happy New Year!
Good news! I can’t wait to test it next month! Michael
What type of JST connector is required for power supply?
Housing
JST PH2P BU
Crimp Contact
JST PH CKB
2mm pitch.
So well just wait for your email with the payment info right? Cant wait to test it
Yes, I’m currently crimping the cables and spot welding the batteries, etc.
I will send out a bunch of emails every time I have a sufficient amount of accessories. I hope that by the end of January, everything will have been shipped.
Dirk.
Hi Dirk,
I am happy to share that I have received my package (PCB, PowerDongle, Battery and USB-Cable) in good condition.
Have fitted it to my Sensostar yesterday and it is working like a charm.
Thank you very much for all your effort and your excellent work!!!
Ole
The second batch of orders has now been fully processed. Anyone who ordered an adapter should have received an email containing payment information.
All orders paid for by today have already been shipped.
Any orders that have not been paid for within 10 days will be automatically cancelled. There are some people on the waiting list. I will offer these adapters to them.
Regards,
Dirk
The PCB has arrived today and I installed it instantly.
It works like a charm!
Many Thanks to @STB3 for the good work.
I have an Brummerhoop F90U3 Sensor which comes from the same manufacturer as the Sensostar.
Thanks for the fast delivery. The PCB arrived today. Installation was easy. Your documentation is perfect! I can confirm: it works also well with “Wassergeräte GmbH - Volumess VI-E”. they seem to use the same chinese manufacturer as Sensostar and Brummerhoop.
Thanks for the board. Easy to install with your instruction, took just 10 minutes. Most struggle was about opening the plastic case 
I can confirm that it works with a “Molline Wingman C3” which is obviously a rebranded Engelmann Sensostar.
Thanks a lot for this fantastic project !
Uwe
Dirk, thank You very much. Installation worked fine and I was very much surprised to see the values immediately in my HomeAssistant System! Very nice and many thanks!!
Roland
Yes, it looks like there is no data coming from the heat meter as is.
Did you flash modifications to the board or is it the stock firmware it came with?
Could you post a picture of the MBUS module? I’d like to compare it with mine to see if there are any differences.
Is the red LED blinking?
Regards,
Dirk
Hi Dirk,
No, it’s not the firmware you played. I compiled it with the following yaml using esphome 2025.12.6. The red LED is not flashing.
# Flash using --device COMXX otherwise it is difficult to flash using USB
esphome:
name: sensostar-v2
name_add_mac_suffix: false
comment: SensoStar Energy Meter
platformio_options:
board_build.arduino.memory_type: qio_opi
on_boot:
then:
- mqtt.disable:
- output.turn_off: adc_control # IO14 LOW at boot
- script.execute: read_adc_script # Immediately read ADC once at boot
- lambda: |-
if (!id(wifi_connected)) {
id(ap_mode_blink).execute();
}
# id(api_key_text).publish_state("${api_key_display}"); # uncommet if you want to use an api key
esp32:
variant: esp32c6
framework:
type: esp-idf
wifi:
# Uncomment this if you have ented your credentials in the secrets.yaml
# anyway at least the api_encryption_key: section must be present in the secrets.yaml
use_address: esphome-sensostar-xxxx.fritz.box
ssid: !secret wifi_ssid
password: !secret wifi_password
power_save_mode: NONE
ap:
ssid: "Sensostar"
reboot_timeout: 0s
on_connect:
- script.stop: ap_mode_blink
- output.turn_on: wifi_led
- lambda: |-
if (id(mqtt_enabled).state) {
ESP_LOGI("wifi", "Wi-Fi connected and MQTT switch is ON — enabling MQTT");
id(mqtt_broker).enable();
}
on_disconnect:
- script.execute: ap_mode_blink
captive_portal:
logger:
level: info
# hardware_uart: UART0
# baud_rate: 115200
api:
encryption: # uncommet if you want to use an api key
key: "GzGxxxxxxxxxxxxxxxLJZkW40+Qok=" # create use openssl rand -base64 32 # uncommet if you want to use an api key
reboot_timeout: 600min
ota:
platform: esphome
password: "8xxxxxxxxxxxx5d5a"
web_server:
version: 3
port: 80
external_components:
# - source: github://pr#8103
# components: [uart]
- source:
#type: local
#path: !secret local_path
type: git # Be careful ESPhome is caching the repository. Do the following to update the cache
url: https://github.com/STB3/esphome-sensostar # Deleting the .esphome/external_components/ cache, or
ref: main # or a specific commit SHA # Using a ref: to pin to a specific commit or branch.
components: [ SensoStar_MBus ]
time:
- platform: sntp
id: sntp_time
timezone: Europe/Amsterdam
servers: ["0.nl.pool.ntp.org", "1.nl.pool.ntp.org", "2.nl.pool.ntp.org"]
uart:
- id: uart_mbus
tx_pin: GPIO6
rx_pin: GPIO7
baud_rate: 2400
parity: EVEN
SensoStar_MBus:
id: sensostar_id
uart_id: uart_mbus
update_interval: 10s
data_led: mbus_data_led
sensor:
- platform: SensoStar_MBus
energy:
name: "SensoStar Energy"
volume:
name: "SensoStar Volume"
power:
name: "SensoStar Power"
# on_value:
# then:
# - output.turn_on: mbus_yellow_led
# - delay: 200ms
# - output.turn_off: mbus_yellow_led
flow:
name: "SensoStar Flow"
temperature_flow:
name: "SensoStar Flow Temperature"
temperature_return:
name: "SensoStar Return Temperature"
temperature_diff:
name: "SensoStar Temperature Difference"
calculated_power:
name: "SensoStar Calculated Power"
- platform: adc
pin: GPIO1
id: adc_input_sensor
name: "SensoStar Battery Level"
update_interval: never # done by interval:
filters:
- lambda: return x * 3.6; # Vbat is measured via a resistive divider 39k--o--15k
- platform: wifi_signal
name: "SensoStar WiFi Signal"
id: wifi_signal_sensor
update_interval: 60s
substitutions:
api_key_display: "GzGXiZFbY8xslEQVoSnEZdwT7Fcwh80bLJZkW40+Qok=" #!secret api_encryption_key
text_sensor:
- platform: SensoStar_MBus
status:
name: "SensoStar Status"
# Show API encryption key in the web interface
# - platform: template # uncommet if you want to use an api key
# name: "API Encryption Key" # uncommet if you want to use an api key
# id: api_key_text # uncommet if you want to use an api key
# entity_category: config # uncommet if you want to use an api key
# lambda: |- # uncommet if you want to use an api key
# return std::string("${api_key_display}");# uncommet if you want to use an api key
# update_interval: never # uncommet if you want to use an api key
output:
- platform: gpio
pin: GPIO14
id: adc_control
- platform: gpio
pin: GPIO4
id: heartbeat_output
- platform: gpio
pin: GPIO3
id: wifi_led
- platform: gpio
pin: GPIO2
id: mbus_data_led
- platform: gpio
pin: GPIO5
id: mbus_yellow_led
script:
- id: read_adc_script
then:
- output.turn_on: adc_control # Set IO14 HIGH
- delay: 8ms # wait until the capacitor on the resistive divider is charged
- component.update: adc_input_sensor # Trigger ADC read
- output.turn_off: adc_control # Set IO14 LOW
- id: ap_mode_blink
mode: restart
then:
# - logger.log: "AP mode blinking started"
- while:
condition:
lambda: 'return !id(wifi_connected);'
then:
- output.turn_on: wifi_led
- delay: 200ms
- output.turn_off: wifi_led
- delay: 1000ms
interval:
- interval: 600s
then:
- script.execute: read_adc_script
- interval: 5s
then:
- light.turn_on: heartbeat_led
- delay: 500ms
- light.turn_off: heartbeat_led
button:
- platform: template
name: "Read battery level now"
on_press:
then:
- script.execute: read_adc_script
- platform: template
name: "Read WiFi Signal now"
on_press:
then:
- component.update: wifi_signal_sensor
light:
- platform: binary
id: heartbeat_led
output: heartbeat_output
internal: true # hide from Home Assistant unless needed
binary_sensor:
- platform: status
name: "ESP Status"
id: esp_status
internal: true # hide from Home Assistant unless needed
globals:
- id: wifi_connected
type: bool
restore_value: no
initial_value: 'false'
mqtt:
enable_on_boot: false
broker: ""
id: mqtt_broker
username: ""
password: ""
text:
- platform: template
mode: text
name: "1. MQTT address"
id: "broker_address"
icon: "mdi:text"
optimistic: true
internal: false
entity_category: config
initial_value: ""
restore_value: true
on_value:
then:
- logger.log:
format: "%s"
args: ["x.c_str()"]
- lambda: |-
id(mqtt_broker).set_broker_address(x.c_str());
ESP_LOGI("mqtt", "MQTT broker set to %s", x.c_str());
- platform: template
mode: text
name: "3. MQTT Username"
id: "mqtt_user"
icon: "mdi:text"
optimistic: true
internal: false
entity_category: config
initial_value: ""
restore_value: true
on_value:
then:
- logger.log:
format: "%s"
args: ["x.c_str()"]
- lambda: |-
id(mqtt_broker).set_username(x.c_str());
ESP_LOGI("mqtt", "MQTT user set to %s", x.c_str());
- platform: template
mode: password
name: "4. MQTT Password"
id: "mqtt_pwd"
icon: "mdi:text"
optimistic: true
internal: false
entity_category: config
initial_value: ""
restore_value: true
on_value:
then:
- logger.log:
format: "%s"
args: ["x.c_str()"]
- lambda: |-
id(mqtt_broker).set_password(x.c_str());
ESP_LOGI("mqtt", "MQTT password set to %s", x.c_str());
- platform: template
mode: text
name: "3. MQTT Port"
id: "mqtt_port"
icon: "mdi:text"
optimistic: true
internal: false
entity_category: config
initial_value: "1883"
restore_value: true
on_value:
then:
- logger.log:
format: "%s"
args: ["x.c_str()"]
- lambda: |-
// Convert string to integer
uint16_t port = (uint16_t) atoi(x.c_str());
// Safety check (valid range for MQTT ports)
if (port < 1 || port > 65535) {
ESP_LOGW("mqtt", "Invalid port %d, ignoring", port);
} else {
id(mqtt_broker).set_broker_port(port);
ESP_LOGI("mqtt", "MQTT Port set to %d", port);
}
switch:
- platform: template
name: "MQTT Enabled"
id: mqtt_enabled
optimistic: true
restore_mode: "RESTORE_DEFAULT_OFF"
entity_category: config
turn_off_action:
- logger.log: "MQTT disabled"
- mqtt.disable:
- lambda: |-
ESP_LOGI("mqtt", "MQTT: disabled.");
turn_on_action:
- lambda: |-
// Get values from text/number inputs
std::string addr = id(broker_address).state;
uint16_t port = (uint16_t)atoi(id(mqtt_port).state.c_str());
// Validate broker address
if (addr.empty()) {
ESP_LOGW("mqtt", "Cannot enable MQTT: broker address is empty");
id(mqtt_enabled).turn_off();
return;
}
// Validate port
if (port < 1 || port > 65535) {
ESP_LOGW("mqtt", "Cannot enable MQTT: invalid port %d", port);
id(mqtt_enabled).turn_off();
return;
}
// All checks passed, enable MQTT
ESP_LOGI("mqtt", "MQTT enabled on %s:%d", addr.c_str(), port);
id(mqtt_broker).set_broker_address(addr.c_str());
id(mqtt_broker).set_broker_port(port);
id(mqtt_broker).set_username(id(mqtt_user).state.c_str());
id(mqtt_broker).set_password(id(mqtt_pwd).state.c_str());
// Non-blocking delay of 1 second before enabling MQTT
App.scheduler.set_timeout(nullptr, "mqtt_enable", 1000, []() {
id(mqtt_broker).enable(); });
return;
Michael