diff --git a/homeassistant/components/flexit_bacnet/quality_scale.yaml b/homeassistant/components/flexit_bacnet/quality_scale.yaml
index eb649656c9d..7a98eda4eb3 100644
--- a/homeassistant/components/flexit_bacnet/quality_scale.yaml
+++ b/homeassistant/components/flexit_bacnet/quality_scale.yaml
@@ -52,7 +52,7 @@ rules:
     status: exempt
     comment: |
       Integration doesn't require any form of authentication.
-  test-coverage: todo
+  test-coverage: done
   # Gold
   entity-translations: done
   entity-device-class: done
diff --git a/tests/components/flexit_bacnet/test_climate.py b/tests/components/flexit_bacnet/test_climate.py
index 5baac1c5077..be361541c39 100644
--- a/tests/components/flexit_bacnet/test_climate.py
+++ b/tests/components/flexit_bacnet/test_climate.py
@@ -1,19 +1,32 @@
 """Tests for the Flexit Nordic (BACnet) climate entity."""
 
+import asyncio
 from unittest.mock import AsyncMock
 
-from flexit_bacnet import VENTILATION_MODE_AWAY, VENTILATION_MODE_HOME
+from flexit_bacnet import (
+    VENTILATION_MODE_AWAY,
+    VENTILATION_MODE_HOME,
+    VENTILATION_MODE_STOP,
+)
+import pytest
 from syrupy.assertion import SnapshotAssertion
 
 from homeassistant.components.climate import (
+    ATTR_HVAC_ACTION,
+    ATTR_HVAC_MODE,
     ATTR_PRESET_MODE,
     PRESET_AWAY,
     PRESET_HOME,
+    SERVICE_SET_HVAC_MODE,
     SERVICE_SET_PRESET_MODE,
+    SERVICE_SET_TEMPERATURE,
+    HVACAction,
+    HVACMode,
 )
 from homeassistant.components.flexit_bacnet.const import PRESET_TO_VENTILATION_MODE_MAP
-from homeassistant.const import ATTR_ENTITY_ID, Platform
+from homeassistant.const import ATTR_ENTITY_ID, ATTR_TEMPERATURE, Platform
 from homeassistant.core import HomeAssistant
+from homeassistant.exceptions import HomeAssistantError
 from homeassistant.helpers import entity_registry as er
 
 from . import setup_with_selected_platforms
@@ -81,3 +94,128 @@ async def test_set_hvac_preset_mode(
     mock_flexit_bacnet.set_ventilation_mode.assert_called_with(
         PRESET_TO_VENTILATION_MODE_MAP[PRESET_HOME]
     )
+
+    mock_flexit_bacnet.set_ventilation_mode.side_effect = asyncio.TimeoutError
+    with pytest.raises(HomeAssistantError):
+        await hass.services.async_call(
+            Platform.CLIMATE,
+            SERVICE_SET_PRESET_MODE,
+            {
+                ATTR_ENTITY_ID: ENTITY_ID,
+                ATTR_PRESET_MODE: PRESET_AWAY,
+            },
+            blocking=True,
+        )
+
+    mock_flexit_bacnet.set_ventilation_mode.assert_called_with(
+        PRESET_TO_VENTILATION_MODE_MAP[PRESET_AWAY]
+    )
+
+
+async def test_set_hvac_mode(
+    hass: HomeAssistant,
+    mock_flexit_bacnet: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test setting HVAC mode."""
+    await setup_with_selected_platforms(hass, mock_config_entry, [Platform.CLIMATE])
+
+    mock_flexit_bacnet.ventilation_mode = VENTILATION_MODE_STOP
+    await hass.services.async_call(
+        Platform.CLIMATE,
+        SERVICE_SET_HVAC_MODE,
+        {ATTR_ENTITY_ID: ENTITY_ID, ATTR_HVAC_MODE: HVACMode.OFF},
+        blocking=True,
+    )
+
+    state = hass.states.get(ENTITY_ID)
+    assert state.state == HVACMode.OFF
+    mock_flexit_bacnet.set_ventilation_mode.assert_called_once_with(
+        VENTILATION_MODE_STOP
+    )
+
+    mock_flexit_bacnet.set_ventilation_mode.side_effect = asyncio.TimeoutError
+    with pytest.raises(HomeAssistantError):
+        await hass.services.async_call(
+            Platform.CLIMATE,
+            SERVICE_SET_HVAC_MODE,
+            {ATTR_ENTITY_ID: ENTITY_ID, ATTR_HVAC_MODE: HVACMode.OFF},
+            blocking=True,
+        )
+
+    mock_flexit_bacnet.set_ventilation_mode.assert_called_with(VENTILATION_MODE_STOP)
+
+
+async def test_hvac_action(
+    hass: HomeAssistant,
+    mock_flexit_bacnet: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test hvac_action property."""
+    await setup_with_selected_platforms(hass, mock_config_entry, [Platform.CLIMATE])
+
+    # Simulate electric heater being ON
+    mock_flexit_bacnet.electric_heater = True
+    await hass.helpers.entity_component.async_update_entity(ENTITY_ID)
+
+    state = hass.states.get(ENTITY_ID)
+    assert state.attributes[ATTR_HVAC_ACTION] == HVACAction.HEATING
+
+    # Simulate electric heater being OFF
+    mock_flexit_bacnet.electric_heater = False
+    await hass.helpers.entity_component.async_update_entity(ENTITY_ID)
+
+    state = hass.states.get(ENTITY_ID)
+    assert state.attributes[ATTR_HVAC_ACTION] == HVACAction.FAN
+
+
+async def test_set_temperature(
+    hass: HomeAssistant,
+    mock_flexit_bacnet: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+) -> None:
+    """Test setting the temperature."""
+    await setup_with_selected_platforms(hass, mock_config_entry, [Platform.CLIMATE])
+
+    # Set ventilation mode to HOME and set temperature to 22.5°C
+    mock_flexit_bacnet.ventilation_mode = VENTILATION_MODE_HOME
+    await hass.services.async_call(
+        Platform.CLIMATE,
+        SERVICE_SET_TEMPERATURE,
+        {
+            ATTR_ENTITY_ID: ENTITY_ID,
+            ATTR_TEMPERATURE: 22.5,
+        },
+        blocking=True,
+    )
+
+    # Ensure that the correct method was called
+    mock_flexit_bacnet.set_air_temp_setpoint_home.assert_called_once_with(22.5)
+
+    # Change ventilation mode to AWAY and set temperature
+    mock_flexit_bacnet.ventilation_mode = VENTILATION_MODE_AWAY
+    await hass.services.async_call(
+        Platform.CLIMATE,
+        SERVICE_SET_TEMPERATURE,
+        {
+            ATTR_ENTITY_ID: ENTITY_ID,
+            ATTR_TEMPERATURE: 18.0,
+        },
+        blocking=True,
+    )
+
+    # Ensure that the correct method was called
+    mock_flexit_bacnet.set_air_temp_setpoint_away.assert_called_once_with(18.0)
+
+    # Test handling of connection errors
+    mock_flexit_bacnet.set_air_temp_setpoint_away.side_effect = ConnectionError
+    with pytest.raises(HomeAssistantError):
+        await hass.services.async_call(
+            Platform.CLIMATE,
+            SERVICE_SET_TEMPERATURE,
+            {
+                ATTR_ENTITY_ID: ENTITY_ID,
+                ATTR_TEMPERATURE: 20.0,
+            },
+            blocking=True,
+        )