diff --git a/homeassistant/components/indevolt/binary_sensor.py b/homeassistant/components/indevolt/binary_sensor.py
index 109a9488f6bb..1be4bf6364a5 100644
--- a/homeassistant/components/indevolt/binary_sensor.py
+++ b/homeassistant/components/indevolt/binary_sensor.py
@@ -46,6 +46,8 @@ BINARY_SENSORS: Final = (
         key=IndevoltSystem.HEATING_STATE,
         generation=(1,),
         translation_key="electric_heating_state",
+        on_value=1000,
+        off_value=1001,
         entity_category=EntityCategory.DIAGNOSTIC,
         entity_registry_enabled_default=False,
     ),
diff --git a/homeassistant/components/indevolt/sensor.py b/homeassistant/components/indevolt/sensor.py
index eb6379191938..1331d7b0356f 100644
--- a/homeassistant/components/indevolt/sensor.py
+++ b/homeassistant/components/indevolt/sensor.py
@@ -939,12 +939,24 @@ class IndevoltSensorEntity(IndevoltEntity, SensorEntity):
 
     @property
     def available(self) -> bool:
-        """Return False when the device is not in the required energy mode."""
+        """Return False for sensors in a non-applicable state."""
+
+        # Check whether device is not in the required energy mode
         if self.entity_description.energy_mode is not None:
             energy_mode = self.coordinator.data.get(IndevoltConfig.READ_ENERGY_MODE)
             if energy_mode != self.entity_description.energy_mode:
                 return False
 
+        # Check whether inverter is reporting 0 degrees with heater not active (thus reporting to indicate "idle")
+        # Pending fix by Indevolt: https://discord.com/channels/1417471269942591571/1510277757689659522
+        if self.entity_description.key == IndevoltBattery.GEN_1_INVERTER_TEMPERATURE:
+            inverter_temp = self.coordinator.data.get(
+                IndevoltBattery.GEN_1_INVERTER_TEMPERATURE
+            )
+            heating_state = self.coordinator.data.get(IndevoltSystem.HEATING_STATE)
+            if inverter_temp == 0 and heating_state != 1000:
+                return False
+
         return super().available
 
     @property
diff --git a/tests/components/indevolt/fixtures/gen_1.json b/tests/components/indevolt/fixtures/gen_1.json
index 6dcb05a0612a..676d4ed1d221 100644
--- a/tests/components/indevolt/fixtures/gen_1.json
+++ b/tests/components/indevolt/fixtures/gen_1.json
@@ -31,7 +31,7 @@
   "6006": 277.16,
   "6007": 256.39,
   "7120": 1000,
-  "7121": 1,
+  "7121": 1001,
   "7600": 35.2,
   "7605": 28.1,
   "7620": 27.4,
diff --git a/tests/components/indevolt/snapshots/test_binary_sensor.ambr b/tests/components/indevolt/snapshots/test_binary_sensor.ambr
index c122ef7f1da7..e18c4c3425e1 100644
--- a/tests/components/indevolt/snapshots/test_binary_sensor.ambr
+++ b/tests/components/indevolt/snapshots/test_binary_sensor.ambr
@@ -46,7 +46,7 @@
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,
-    'state': 'on',
+    'state': 'off',
   })
 # ---
 # name: test_binary_sensor[1][binary_sensor.bk1600_meter_connected-entry]
diff --git a/tests/components/indevolt/snapshots/test_diagnostics.ambr b/tests/components/indevolt/snapshots/test_diagnostics.ambr
index 1e7a2cc4c9f3..6f143b00a579 100644
--- a/tests/components/indevolt/snapshots/test_diagnostics.ambr
+++ b/tests/components/indevolt/snapshots/test_diagnostics.ambr
@@ -34,7 +34,7 @@
       '667': 0,
       '7101': 5,
       '7120': 1000,
-      '7121': 1,
+      '7121': 1001,
       '7600': 35.2,
       '7605': 28.1,
       '7620': 27.4,
diff --git a/tests/components/indevolt/test_sensor.py b/tests/components/indevolt/test_sensor.py
index 247dc34899bb..32597a0ecbb1 100644
--- a/tests/components/indevolt/test_sensor.py
+++ b/tests/components/indevolt/test_sensor.py
@@ -4,7 +4,12 @@ from datetime import timedelta
 from unittest.mock import AsyncMock, patch
 
 from freezegun.api import FrozenDateTimeFactory
-from indevolt_api import IndevoltConfig, IndevoltEnergyMode
+from indevolt_api import (
+    IndevoltBattery,
+    IndevoltConfig,
+    IndevoltEnergyMode,
+    IndevoltSystem,
+)
 import pytest
 from syrupy.assertion import SnapshotAssertion
 
@@ -115,6 +120,43 @@ async def test_realtime_sensor_energy_mode_availability(
     )
 
 
+@pytest.mark.usefixtures("entity_registry_enabled_by_default")
+@pytest.mark.parametrize("generation", [1], indirect=True)
+async def test_inverter_sensor_temperature_availability(
+    hass: HomeAssistant,
+    mock_indevolt: AsyncMock,
+    mock_config_entry: MockConfigEntry,
+    freezer: FrozenDateTimeFactory,
+) -> None:
+    """Test inverter sensors are only available when temperature is reported."""
+    with patch("homeassistant.components.indevolt.PLATFORMS", [Platform.SENSOR]):
+        await setup_integration(hass, mock_config_entry)
+
+    # Default fixture reports a valid temperature (35.2) with heating off, sensor should be available
+    assert hass.states.get("sensor.bk1600_inverter_temperature").state == "35.2"
+
+    # Set temperature to 0 with heating off - sensor should become unavailable
+    mock_indevolt.fetch_data.return_value[
+        IndevoltBattery.GEN_1_INVERTER_TEMPERATURE
+    ] = 0
+
+    freezer.tick(delta=timedelta(seconds=SCAN_INTERVAL))
+    async_fire_time_changed(hass)
+    await hass.async_block_till_done()
+
+    assert (
+        hass.states.get("sensor.bk1600_inverter_temperature").state == STATE_UNAVAILABLE
+    )
+
+    # Switch heating on, sensor should be available again with value 0
+    mock_indevolt.fetch_data.return_value[IndevoltSystem.HEATING_STATE] = 1000
+    freezer.tick(delta=timedelta(seconds=SCAN_INTERVAL))
+    async_fire_time_changed(hass)
+    await hass.async_block_till_done()
+
+    assert hass.states.get("sensor.bk1600_inverter_temperature").state == "0"
+
+
 # In individual tests, you can override the mock behavior
 async def test_battery_pack_filtering(
     hass: HomeAssistant,