diff --git a/homeassistant/components/vistapool/__init__.py b/homeassistant/components/vistapool/__init__.py
index fd7321a16625a6..d5b08f07066893 100644
--- a/homeassistant/components/vistapool/__init__.py
+++ b/homeassistant/components/vistapool/__init__.py
@@ -16,7 +16,12 @@
 
 _LOGGER = logging.getLogger(__name__)
 
-PLATFORMS: list[Platform] = [Platform.BUTTON, Platform.NUMBER, Platform.SENSOR]
+PLATFORMS: list[Platform] = [
+    Platform.BUTTON,
+    Platform.NUMBER,
+    Platform.SENSOR,
+    Platform.SWITCH,
+]
 
 
 @dataclass
diff --git a/homeassistant/components/vistapool/strings.json b/homeassistant/components/vistapool/strings.json
index e12ecfe545ec39..79377ff911fe74 100644
--- a/homeassistant/components/vistapool/strings.json
+++ b/homeassistant/components/vistapool/strings.json
@@ -89,6 +89,26 @@
       "uv": {
         "name": "UV"
       }
+    },
+    "switch": {
+      "electrolysis_boost": {
+        "name": "Electrolysis boost"
+      },
+      "electrolysis_cover": {
+        "name": "Electrolysis cover"
+      },
+      "filtration": {
+        "name": "Filtration"
+      },
+      "heating_climate": {
+        "name": "Heating climate"
+      },
+      "relay": {
+        "name": "Relay {number}"
+      },
+      "smart_mode_freeze": {
+        "name": "Smart mode freeze"
+      }
     }
   },
   "exceptions": {
diff --git a/homeassistant/components/vistapool/switch.py b/homeassistant/components/vistapool/switch.py
new file mode 100644
index 00000000000000..90bb9fa0299a75
--- /dev/null
+++ b/homeassistant/components/vistapool/switch.py
@@ -0,0 +1,163 @@
+"""Vistapool Switch entities."""
+
+from dataclasses import dataclass
+from typing import Any
+
+from aioaquarite import AquariteError
+
+from homeassistant.components.switch import SwitchEntity, SwitchEntityDescription
+from homeassistant.core import HomeAssistant
+from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
+
+from . import VistapoolConfigEntry
+from .const import DOMAIN, PATH_HASHIDRO
+from .coordinator import VistapoolDataUpdateCoordinator
+from .entity import VistapoolEntity
+
+PARALLEL_UPDATES = 1
+
+
+@dataclass(frozen=True, kw_only=True)
+class VistapoolSwitchEntityDescription(SwitchEntityDescription):
+    """Describes a Vistapool switch entity."""
+
+    value_path: str
+    is_relay: bool = False
+    exists_path: str | tuple[str, ...] | None = None
+    translation_placeholders: dict[str, str] | None = None
+
+
+SWITCH_DESCRIPTIONS: tuple[VistapoolSwitchEntityDescription, ...] = (
+    VistapoolSwitchEntityDescription(
+        key="filtration",
+        translation_key="filtration",
+        value_path="filtration.status",
+    ),
+    *(
+        VistapoolSwitchEntityDescription(
+            key=f"relay_{i}",
+            translation_key="relay",
+            translation_placeholders={"number": str(i)},
+            value_path=f"relays.relay{i}.info.onoff",
+            is_relay=True,
+        )
+        for i in (1, 2, 3, 4)
+    ),
+    VistapoolSwitchEntityDescription(
+        key="electrolysis_cover",
+        translation_key="electrolysis_cover",
+        value_path="hidro.cover_enabled",
+        exists_path=PATH_HASHIDRO,
+    ),
+    VistapoolSwitchEntityDescription(
+        key="electrolysis_boost",
+        translation_key="electrolysis_boost",
+        value_path="hidro.cloration_enabled",
+        exists_path=PATH_HASHIDRO,
+    ),
+)
+
+
+async def async_setup_entry(
+    hass: HomeAssistant,
+    entry: VistapoolConfigEntry,
+    async_add_entities: AddConfigEntryEntitiesCallback,
+) -> None:
+    """Set up Vistapool switches for every pool on the account."""
+    entities: list[SwitchEntity] = []
+
+    for coordinator in entry.runtime_data.coordinators.values():
+        for description in SWITCH_DESCRIPTIONS:
+            if description.exists_path is not None:
+                required = (
+                    (description.exists_path,)
+                    if isinstance(description.exists_path, str)
+                    else description.exists_path
+                )
+                if not all(coordinator.get_value(path) for path in required):
+                    continue
+            entities.append(VistapoolSwitch(coordinator, description))
+
+        if coordinator.get_value("filtration.hasHeat"):
+            entities.append(
+                VistapoolSwitch(
+                    coordinator,
+                    VistapoolSwitchEntityDescription(
+                        key="heating_climate",
+                        translation_key="heating_climate",
+                        value_path="filtration.heating.clima",
+                    ),
+                )
+            )
+
+        if coordinator.get_value("filtration.hasSmart"):
+            entities.append(
+                VistapoolSwitch(
+                    coordinator,
+                    VistapoolSwitchEntityDescription(
+                        key="smart_mode_freeze",
+                        translation_key="smart_mode_freeze",
+                        value_path="filtration.smart.freeze",
+                    ),
+                )
+            )
+
+    async_add_entities(entities)
+
+
+class VistapoolSwitch(VistapoolEntity, SwitchEntity):
+    """Generic Vistapool switch driven by an entity description."""
+
+    entity_description: VistapoolSwitchEntityDescription
+
+    def __init__(
+        self,
+        coordinator: VistapoolDataUpdateCoordinator,
+        description: VistapoolSwitchEntityDescription,
+    ) -> None:
+        """Initialize the switch."""
+        super().__init__(coordinator)
+        self.entity_description = description
+        self._attr_unique_id = self.build_unique_id(description.key)
+        if description.translation_placeholders is not None:
+            self._attr_translation_placeholders = description.translation_placeholders
+
+    @property
+    def is_on(self) -> bool | None:
+        """Return true if the switch is on."""
+        value = self.coordinator.get_value(self.entity_description.value_path)
+        if value is None:
+            return None
+        on = value in (True, "1")
+        if self.entity_description.is_relay:
+            # Relays report a separate read-only `status` next to the writable
+            # `onoff`; show the switch as on when either is truthy.
+            status_path = self.entity_description.value_path.replace("onoff", "status")
+            status = self.coordinator.get_value(status_path)
+            if status is not None:
+                on = on or status in (True, "1")
+        return on
+
+    async def async_turn_on(self, **kwargs: Any) -> None:
+        """Turn the switch on."""
+        await self._async_set_value(1)
+
+    async def async_turn_off(self, **kwargs: Any) -> None:
+        """Turn the switch off."""
+        await self._async_set_value(0)
+
+    async def _async_set_value(self, value: int) -> None:
+        """Send a value update via the Vistapool cloud API."""
+        try:
+            await self.coordinator.api.set_value(
+                self.coordinator.pool_id,
+                self.entity_description.value_path,
+                value,
+            )
+        except AquariteError as err:
+            raise HomeAssistantError(
+                translation_domain=DOMAIN,
+                translation_key="set_failed",
+                translation_placeholders={"entity": self.entity_id},
+            ) from err
diff --git a/tests/components/vistapool/snapshots/test_switch.ambr b/tests/components/vistapool/snapshots/test_switch.ambr
new file mode 100644
index 00000000000000..e3ee3ae9c7e4aa
--- /dev/null
+++ b/tests/components/vistapool/snapshots/test_switch.ambr
@@ -0,0 +1,351 @@
+# serializer version: 1
+# name: test_all_entities[switch.my_pool_electrolysis_boost-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_electrolysis_boost',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Electrolysis boost',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Electrolysis boost',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'electrolysis_boost',
+    'unique_id': 'ABCDEF1234567890-electrolysis_boost',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_electrolysis_boost-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Electrolysis boost',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_electrolysis_boost',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_electrolysis_cover-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_electrolysis_cover',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Electrolysis cover',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Electrolysis cover',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'electrolysis_cover',
+    'unique_id': 'ABCDEF1234567890-electrolysis_cover',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_electrolysis_cover-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Electrolysis cover',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_electrolysis_cover',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_filtration-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_filtration',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Filtration',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Filtration',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'filtration',
+    'unique_id': 'ABCDEF1234567890-filtration',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_filtration-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Filtration',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_filtration',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'on',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_1-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_relay_1',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Relay 1',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Relay 1',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'relay',
+    'unique_id': 'ABCDEF1234567890-relay_1',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_1-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Relay 1',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_relay_1',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_2-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_relay_2',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Relay 2',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Relay 2',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'relay',
+    'unique_id': 'ABCDEF1234567890-relay_2',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_2-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Relay 2',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_relay_2',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_3-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_relay_3',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Relay 3',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Relay 3',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'relay',
+    'unique_id': 'ABCDEF1234567890-relay_3',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_3-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Relay 3',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_relay_3',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_4-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': None,
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'switch',
+    'entity_category': None,
+    'entity_id': 'switch.my_pool_relay_4',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Relay 4',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Relay 4',
+    'platform': 'vistapool',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': 'relay',
+    'unique_id': 'ABCDEF1234567890-relay_4',
+    'unit_of_measurement': None,
+  })
+# ---
+# name: test_all_entities[switch.my_pool_relay_4-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      'friendly_name': 'My Pool Relay 4',
+    }),
+    'context': <ANY>,
+    'entity_id': 'switch.my_pool_relay_4',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': 'off',
+  })
+# ---
diff --git a/tests/components/vistapool/test_switch.py b/tests/components/vistapool/test_switch.py
new file mode 100644
index 00000000000000..7311dfd58ac199
--- /dev/null
+++ b/tests/components/vistapool/test_switch.py
@@ -0,0 +1,167 @@
+"""Tests for the Vistapool switch platform."""
+
+from collections.abc import Generator
+from typing import Any
+from unittest.mock import AsyncMock, patch
+
+from aioaquarite import AquariteError
+import pytest
+from syrupy.assertion import SnapshotAssertion
+
+from homeassistant.components.switch import (
+    DOMAIN as SWITCH_DOMAIN,
+    SERVICE_TURN_OFF,
+    SERVICE_TURN_ON,
+)
+from homeassistant.const import ATTR_ENTITY_ID, STATE_OFF, STATE_ON, Platform
+from homeassistant.core import HomeAssistant
+from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers import entity_registry as er
+
+from tests.common import MockConfigEntry, snapshot_platform
+
+
+@pytest.fixture(autouse=True)
+def _only_switch_platform() -> Generator[None]:
+    """Restrict integration setup to the switch platform for these tests."""
+    with patch("homeassistant.components.vistapool.PLATFORMS", [Platform.SWITCH]):
+        yield
+
+
+async def test_all_entities(
+    hass: HomeAssistant,
+    snapshot: SnapshotAssertion,
+    entity_registry: er.EntityRegistry,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+    mock_pool_data: dict[str, Any],
+) -> None:
+    """Test switch entities for the default fixture."""
+    mock_vistapool_client.fetch_pool_data.return_value = mock_pool_data
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    await snapshot_platform(hass, entity_registry, snapshot, mock_config_entry.entry_id)
+
+
+async def test_switch_relay_status_fallback(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+) -> None:
+    """Test relay switches report on when the read-only status is set."""
+    mock_vistapool_client.fetch_pool_data.return_value = {
+        "main": {"version": 1},
+        "relays": {
+            "relay1": {"info": {"onoff": 0, "status": 1}},
+            "relay2": {"info": {"onoff": 1, "status": 0}},
+            "relay3": {"info": {"onoff": 0, "status": 0}},
+            "relay4": {"info": {"onoff": 0, "status": 0}},
+        },
+    }
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert hass.states.get("switch.my_pool_relay_1").state == STATE_ON
+    assert hass.states.get("switch.my_pool_relay_2").state == STATE_ON
+    assert hass.states.get("switch.my_pool_relay_3").state == STATE_OFF
+
+
+async def test_switch_heating_climate_requires_has_heat(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+) -> None:
+    """Test heating_climate is only created when filtration.hasHeat is set."""
+    mock_vistapool_client.fetch_pool_data.return_value = {
+        "main": {"version": 1},
+        "filtration": {"hasHeat": 1, "heating": {"clima": 0}},
+    }
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert hass.states.get("switch.my_pool_heating_climate") is not None
+    assert hass.states.get("switch.my_pool_smart_mode_freeze") is None
+
+
+async def test_switch_smart_mode_freeze_requires_has_smart(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+) -> None:
+    """Test smart_mode_freeze is only created when filtration.hasSmart is set."""
+    mock_vistapool_client.fetch_pool_data.return_value = {
+        "main": {"version": 1},
+        "filtration": {"hasSmart": 1, "smart": {"freeze": 1}},
+    }
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    assert hass.states.get("switch.my_pool_smart_mode_freeze").state == STATE_ON
+    assert hass.states.get("switch.my_pool_heating_climate") is None
+
+
+@pytest.mark.parametrize(
+    ("service", "expected_value"),
+    [
+        pytest.param(SERVICE_TURN_ON, 1, id="turn_on"),
+        pytest.param(SERVICE_TURN_OFF, 0, id="turn_off"),
+    ],
+)
+async def test_switch_set_value(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+    mock_pool_data: dict[str, Any],
+    service: str,
+    expected_value: int,
+) -> None:
+    """Test turn_on / turn_off call the library's set_value with the right args."""
+    mock_vistapool_client.fetch_pool_data.return_value = mock_pool_data
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    await hass.services.async_call(
+        SWITCH_DOMAIN,
+        service,
+        {ATTR_ENTITY_ID: "switch.my_pool_filtration"},
+        blocking=True,
+    )
+
+    mock_vistapool_client.set_value.assert_awaited_once_with(
+        "ABCDEF1234567890", "filtration.status", expected_value
+    )
+
+
+async def test_switch_set_value_raises_on_api_error(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_vistapool_client: AsyncMock,
+    mock_pool_data: dict[str, Any],
+) -> None:
+    """Test action raises HomeAssistantError when the library fails."""
+    mock_vistapool_client.fetch_pool_data.return_value = mock_pool_data
+    mock_vistapool_client.set_value.side_effect = AquariteError("boom")
+    mock_config_entry.add_to_hass(hass)
+
+    assert await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    with pytest.raises(HomeAssistantError) as excinfo:
+        await hass.services.async_call(
+            SWITCH_DOMAIN,
+            SERVICE_TURN_ON,
+            {ATTR_ENTITY_ID: "switch.my_pool_filtration"},
+            blocking=True,
+        )
+    assert excinfo.value.translation_key == "set_failed"