# Use a Home Assistant temperature sensor

> Send a Home Assistant temperature entity to the controller, including a Govee thermometer received through Bluetooth or a proxy.

Source: https://serin-labs.com/controller/sensors-home-assistant.html
Last updated: 2026-10-27

Send a Home Assistant temperature entity to your ESPHome controller. Home Assistant must keep running to forward readings, including those received through a Bluetooth proxy.

## Before you start

Complete [Home Assistant setup](https://serin-labs.com/esphome/setup.html) and confirm the indoor unit responds. [Save the existing YAML and secrets](https://serin-labs.com/controller/backups.html#esphome) before replacing its configuration.

If you already have a working temperature entity, continue to sending its reading to the controller. For direct controller-to-thermometer operation, use [direct Bluetooth configuration](https://serin-labs.com/controller/sensors-esphome.html).

## Add the included Govee sensor to Home Assistant

The included Govee thermometer needs Home Assistant's **Govee Bluetooth** integration; the standard ESPHome firmware does not read it directly. Use a Bluetooth receiver within range:

- **The Home Assistant computer's Bluetooth adapter:** in **Settings** > **Devices & services**, select **Add** on the discovered Bluetooth card. If absent, select **Add integration** > **Bluetooth**.
- **The controller's Bluetooth proxy:** available automatically after adding the standard ESPHome build to Home Assistant. It appears on the **Bluetooth** integration's page. Use this if the Home Assistant computer lacks Bluetooth, as Home Assistant Green does, or is out of range.

Both receivers can be used together.

1. [Position the thermometer](https://serin-labs.com/controller/room-sensors.html#placement).
2. In **Settings** > **Devices & services**, select **Add** on the discovered Govee Bluetooth device. If absent, select **Add integration** > **Govee Bluetooth** and choose the thermometer.
3. Open the new device, confirm its temperature is current, and copy the sensor's entity ID for the steps below.

If the controller is missing from the Bluetooth integration, enable its proxy in the YAML generator as described below.

## Use a temperature sensor through Home Assistant

Any integration supplying a temperature entity can be used, including Zigbee, Z-Wave, Bluetooth and another ESPHome device.

1. Find the sensor's entity ID in Home Assistant, for example `sensor.living_room_temp`, and confirm it has a current reading.
2. Follow [Customize ESPHome](https://serin-labs.com/controller/customize-esphome.html) to import your existing configuration into the YAML generator.
3. Under **Room temperature source**, enable **Home Assistant temperature sensor** and fill in **Sensor entity ID in Home Assistant**. Without an ID, the generator omits the sensor. Keep the device identity and credentials.
4. Match **Sensor unit in Home Assistant** to the entity's unit. The default is °F; leaving it there for a Celsius sensor causes readings to be ignored.
5. If using the controller's proxy, select **Home Assistant Bluetooth proxy** under **Advanced options**. Otherwise the generated configuration removes the proxy and the thermometer stops reporting.
6. Replace the device's configuration with the generated file and install over Wi-Fi.
7. If you also enabled Serin Link's room sensor, set **Room Temperature Source** in Home Assistant to **Home Assistant**. Only the selected source feeds the heat pump.

Invalid readings are ignored. When remote readings time out, the indoor unit uses its built-in sensor until they resume.

## Verify the source

Confirm the controller's room reading follows the selected entity and a climate command reaches the indoor unit. Check the sensor unit and source selection before calibrating an incorrect reading.

For an unavailable entity, check its integration. If climate control also fails, use [Home Assistant troubleshooting](https://serin-labs.com/troubleshooting.html#esphome).