diff --git a/homeassistant/components/melnor/switch.py b/homeassistant/components/melnor/switch.py
index c2d32c428d3..7a615a8582d 100644
--- a/homeassistant/components/melnor/switch.py
+++ b/homeassistant/components/melnor/switch.py
@@ -48,10 +48,7 @@ class MelnorSwitch(MelnorBluetoothBaseEntity, SwitchEntity):
         super().__init__(coordinator)
         self._valve_index = valve_index
 
-        self._attr_unique_id = (
-            f"switch-{self._attr_unique_id}-zone{self._valve().id}-manual"
-        )
-
+        self._attr_unique_id = f"{self._attr_unique_id}-zone{self._valve().id}-manual"
         self._attr_name = f"{self._device.name} Zone {self._valve().id+1}"
 
     @property