diff --git a/homeassistant/components/touchline_sl/entity.py b/homeassistant/components/touchline_sl/entity.py
index 637ad8955eb8..773ba6dfef75 100644
--- a/homeassistant/components/touchline_sl/entity.py
+++ b/homeassistant/components/touchline_sl/entity.py
@@ -35,4 +35,8 @@ class TouchlineSLZoneEntity(CoordinatorEntity[TouchlineSLModuleCoordinator]):
     @property
     def available(self) -> bool:
         """Return if the device is available."""
-        return super().available and self.zone_id in self.coordinator.data.zones
+        return (
+            super().available
+            and self.zone_id in self.coordinator.data.zones
+            and self.zone.alarm is None
+        )
diff --git a/tests/components/touchline_sl/conftest.py b/tests/components/touchline_sl/conftest.py
index 4edeb048f5bd..8a6f1b01e578 100644
--- a/tests/components/touchline_sl/conftest.py
+++ b/tests/components/touchline_sl/conftest.py
@@ -2,7 +2,7 @@
 
 from collections.abc import Generator
 from typing import NamedTuple
-from unittest.mock import AsyncMock, patch
+from unittest.mock import AsyncMock, MagicMock, patch
 
 import pytest
 
@@ -19,6 +19,39 @@ class FakeModule(NamedTuple):
     id: str
 
 
+def make_mock_zone(
+    zone_id: int = 1, name: str = "Zone 1", alarm: str | None = None
+) -> MagicMock:
+    """Return a mock Zone with configurable alarm state."""
+    zone = MagicMock()
+    zone.id = zone_id
+    zone.name = name
+    zone.temperature = 21.5
+    zone.target_temperature = 22.0
+    zone.humidity = 45
+    zone.mode = "constantTemp"
+    zone.algorithm = "heating"
+    zone.relay_on = False
+    zone.alarm = alarm
+    zone.schedule = None
+    zone.enabled = True
+    zone.signal_strength = 100
+    zone.battery_level = None
+    return zone
+
+
+def make_mock_module(zones: list) -> MagicMock:
+    """Return a mock module with the given zones."""
+    module = MagicMock()
+    module.id = "deadbeef"
+    module.name = "Foobar"
+    module.type = "SL"
+    module.version = "1.0"
+    module.zones = AsyncMock(return_value=zones)
+    module.schedules = AsyncMock(return_value=[])
+    return module
+
+
 @pytest.fixture
 def mock_setup_entry() -> Generator[AsyncMock]:
     """Override async_setup_entry."""
diff --git a/tests/components/touchline_sl/test_climate.py b/tests/components/touchline_sl/test_climate.py
new file mode 100644
index 000000000000..94d50364ff81
--- /dev/null
+++ b/tests/components/touchline_sl/test_climate.py
@@ -0,0 +1,55 @@
+"""Tests for the Roth Touchline SL climate platform."""
+
+from unittest.mock import AsyncMock, MagicMock
+
+import pytest
+
+from homeassistant.components.climate import HVACMode
+from homeassistant.const import STATE_UNAVAILABLE
+from homeassistant.core import HomeAssistant
+
+from .conftest import make_mock_module, make_mock_zone
+
+from tests.common import MockConfigEntry
+
+ENTITY_ID = "climate.zone_1"
+
+
+async def test_climate_zone_available(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_touchlinesl_client: MagicMock,
+) -> None:
+    """Test that the climate entity is available when zone has no alarm."""
+    zone = make_mock_zone(alarm=None)
+    module = make_mock_module([zone])
+    mock_touchlinesl_client.modules = AsyncMock(return_value=[module])
+
+    mock_config_entry.add_to_hass(hass)
+    await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    state = hass.states.get(ENTITY_ID)
+    assert state is not None
+    assert state.state == HVACMode.HEAT
+
+
+@pytest.mark.parametrize("alarm", ["no_communication", "sensor_damaged"])
+async def test_climate_zone_unavailable_on_alarm(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_touchlinesl_client: MagicMock,
+    alarm: str,
+) -> None:
+    """Test that the climate entity is unavailable when zone reports an alarm state."""
+    zone = make_mock_zone(alarm=alarm)
+    module = make_mock_module([zone])
+    mock_touchlinesl_client.modules = AsyncMock(return_value=[module])
+
+    mock_config_entry.add_to_hass(hass)
+    await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    state = hass.states.get(ENTITY_ID)
+    assert state is not None
+    assert state.state == STATE_UNAVAILABLE