diff --git a/homeassistant/components/overkiz/sensor.py b/homeassistant/components/overkiz/sensor.py
index ac32c76c459b880bacde4da7b5e919fc2d503d92..55b865c1aeb4337ba5c521a9299ce417caf334b5 100644
--- a/homeassistant/components/overkiz/sensor.py
+++ b/homeassistant/components/overkiz/sensor.py
@@ -354,10 +354,16 @@ SENSOR_DESCRIPTIONS: list[OverkizSensorDescription] = [
     OverkizSensorDescription(
         key=OverkizState.IO_HEAT_PUMP_OPERATING_TIME,
         name="Heat Pump Operating Time",
+        icon="mdi:home-clock",
+        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",
+        native_unit_of_measurement=TIME_SECONDS,
+        entity_category=EntityCategory.DIAGNOSTIC,
     ),
     # Cover
     OverkizSensorDescription(