diff --git a/homeassistant/components/overkiz/sensor.py b/homeassistant/components/overkiz/sensor.py
index 55b865c1aeb4337ba5c521a9299ce417caf334b5..cbe4234a5acbc00afbf4ad2a07ff97cb84da472e 100644
--- a/homeassistant/components/overkiz/sensor.py
+++ b/homeassistant/components/overkiz/sensor.py
@@ -354,14 +354,14 @@ SENSOR_DESCRIPTIONS: list[OverkizSensorDescription] = [
     OverkizSensorDescription(
         key=OverkizState.IO_HEAT_PUMP_OPERATING_TIME,
         name="Heat Pump Operating Time",
-        icon="mdi:home-clock",
+        device_class=SensorDeviceClass.DURATION,
         entity_category=EntityCategory.DIAGNOSTIC,
         native_unit_of_measurement=TIME_SECONDS,
     ),
     OverkizSensorDescription(
         key=OverkizState.IO_ELECTRIC_BOOSTER_OPERATING_TIME,
         name="Electric Booster Operating Time",
-        icon="mdi:home-clock",
+        device_class=SensorDeviceClass.DURATION,
         native_unit_of_measurement=TIME_SECONDS,
         entity_category=EntityCategory.DIAGNOSTIC,
     ),