diff --git a/homeassistant/components/tradfri/fan.py b/homeassistant/components/tradfri/fan.py
index e01d4d3b574..7b64e883c44 100644
--- a/homeassistant/components/tradfri/fan.py
+++ b/homeassistant/components/tradfri/fan.py
@@ -67,6 +67,7 @@ class TradfriAirPurifierFan(TradfriBaseDevice, FanEntity):
         """Initialize a switch."""
         super().__init__(device, api, gateway_id)
         self._attr_unique_id = f"{gateway_id}-{device.id}"
+        self._refresh(device, write_ha=False)
 
     @property
     def supported_features(self) -> int:
diff --git a/tests/components/tradfri/test_fan.py b/tests/components/tradfri/test_fan.py
new file mode 100644
index 00000000000..13b7e59e103
--- /dev/null
+++ b/tests/components/tradfri/test_fan.py
@@ -0,0 +1,162 @@
+"""Tradfri fan (recognised as air purifiers in the IKEA ecosystem) platform tests."""
+
+from unittest.mock import MagicMock, Mock, PropertyMock, patch
+
+import pytest
+from pytradfri.device import Device
+from pytradfri.device.air_purifier import AirPurifier
+from pytradfri.device.air_purifier_control import AirPurifierControl
+
+from .common import setup_integration
+
+
+@pytest.fixture(autouse=True, scope="module")
+def setup(request):
+    """Set up patches for pytradfri methods."""
+    with patch(
+        "pytradfri.device.AirPurifierControl.raw",
+        new_callable=PropertyMock,
+        return_value=[{"mock": "mock"}],
+    ), patch(
+        "pytradfri.device.AirPurifierControl.air_purifiers",
+    ):
+        yield
+
+
+def mock_fan(test_features=None, test_state=None, device_number=0):
+    """Mock a tradfri fan/air purifier."""
+    if test_features is None:
+        test_features = {}
+    if test_state is None:
+        test_state = {}
+    mock_fan_data = Mock(**test_state)
+
+    dev_info_mock = MagicMock()
+    dev_info_mock.manufacturer = "manufacturer"
+    dev_info_mock.model_number = "model"
+    dev_info_mock.firmware_version = "1.2.3"
+    _mock_fan = Mock(
+        id=f"mock-fan-id-{device_number}",
+        reachable=True,
+        observe=Mock(),
+        device_info=dev_info_mock,
+        has_light_control=False,
+        has_socket_control=False,
+        has_blind_control=False,
+        has_signal_repeater_control=False,
+        has_air_purifier_control=True,
+    )
+    _mock_fan.name = f"tradfri_fan_{device_number}"
+    air_purifier_control = AirPurifierControl(_mock_fan)
+
+    # Store the initial state.
+    setattr(air_purifier_control, "air_purifiers", [mock_fan_data])
+    _mock_fan.air_purifier_control = air_purifier_control
+    return _mock_fan
+
+
+async def test_fan(hass, mock_gateway, mock_api_factory):
+    """Test that fans are correctly added."""
+    state = {
+        "fan_speed": 10,
+    }
+
+    mock_gateway.mock_devices.append(mock_fan(test_state=state))
+    await setup_integration(hass)
+
+    fan_1 = hass.states.get("fan.tradfri_fan_0")
+    assert fan_1 is not None
+    assert fan_1.state == "on"
+    assert fan_1.attributes["percentage"] == 18
+    assert fan_1.attributes["preset_modes"] == ["Auto"]
+    assert fan_1.attributes["supported_features"] == 9
+
+
+async def test_fan_observed(hass, mock_gateway, mock_api_factory):
+    """Test that fans are correctly observed."""
+    state = {
+        "fan_speed": 10,
+    }
+
+    fan = mock_fan(test_state=state)
+    mock_gateway.mock_devices.append(fan)
+    await setup_integration(hass)
+    assert len(fan.observe.mock_calls) > 0
+
+
+async def test_fan_available(hass, mock_gateway, mock_api_factory):
+    """Test fan available property."""
+
+    fan = mock_fan(test_state={"fan_speed": 10}, device_number=1)
+    fan.reachable = True
+
+    fan2 = mock_fan(test_state={"fan_speed": 10}, device_number=2)
+    fan2.reachable = False
+
+    mock_gateway.mock_devices.append(fan)
+    mock_gateway.mock_devices.append(fan2)
+    await setup_integration(hass)
+
+    assert hass.states.get("fan.tradfri_fan_1").state == "on"
+    assert hass.states.get("fan.tradfri_fan_2").state == "unavailable"
+
+
+@pytest.mark.parametrize(
+    "test_data, expected_result",
+    [
+        (
+            {"percentage": 50},
+            "on",
+        ),
+        ({"percentage": 0}, "off"),
+    ],
+)
+async def test_set_percentage(
+    hass,
+    mock_gateway,
+    mock_api_factory,
+    test_data,
+    expected_result,
+):
+    """Test setting speed of a fan."""
+    # Note pytradfri style, not hass. Values not really important.
+    initial_state = {"percentage": 10, "fan_speed": 3}
+
+    # Setup the gateway with a mock fan.
+    fan = mock_fan(test_state=initial_state, device_number=0)
+    mock_gateway.mock_devices.append(fan)
+    await setup_integration(hass)
+
+    # Use the turn_on service call to change the fan state.
+    await hass.services.async_call(
+        "fan",
+        "set_percentage",
+        {"entity_id": "fan.tradfri_fan_0", **test_data},
+        blocking=True,
+    )
+    await hass.async_block_till_done()
+
+    # Check that the fan is observed.
+    mock_func = fan.observe
+    assert len(mock_func.mock_calls) > 0
+    _, callkwargs = mock_func.call_args
+    assert "callback" in callkwargs
+    # Callback function to refresh fan state.
+    callback = callkwargs["callback"]
+
+    responses = mock_gateway.mock_responses
+    mock_gateway_response = responses[0]
+
+    # A KeyError is raised if we don't add the 5908 response code
+    mock_gateway_response["15025"][0].update({"5908": 10})
+
+    # Use the callback function to update the fan state.
+    dev = Device(mock_gateway_response)
+    fan_data = AirPurifier(dev, 0)
+    fan.air_purifier_control.air_purifiers[0] = fan_data
+    callback(fan)
+    await hass.async_block_till_done()
+
+    # Check that the state is correct.
+    state = hass.states.get("fan.tradfri_fan_0")
+    assert state.state == expected_result