Deprecate aux_heat in elkm1 (#125372)

* Deprecate aux_heat in elkm1

* Update homeassistant/components/elkm1/switch.py

---------

Co-authored-by: Joost Lekkerkerker <joostlek@outlook.com>

homeassistant/components/elkm1/climate.py

@@ -20,8 +20,9 @@ from homeassistant.components.climate import (
 from homeassistant.const import PRECISION_WHOLE
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
+from homeassistant.helpers.issue_registry import IssueSeverity, async_create_issue
 
-from . import ElkEntity, ElkM1ConfigEntry, create_elk_entities
+from . import DOMAIN, ElkEntity, ElkM1ConfigEntry, create_elk_entities
 
 SUPPORT_HVAC = [
     HVACMode.OFF,
@@ -151,10 +152,30 @@ class ElkThermostat(ElkEntity, ClimateEntity):
 
     async def async_turn_aux_heat_on(self) -> None:
         """Turn auxiliary heater on."""
+        async_create_issue(
+            self.hass,
+            DOMAIN,
+            "migrate_aux_heat",
+            breaks_in_ha_version="2025.4.0",
+            is_fixable=True,
+            is_persistent=True,
+            translation_key="migrate_aux_heat",
+            severity=IssueSeverity.WARNING,
+        )
         self._elk_set(ThermostatMode.EMERGENCY_HEAT, None)
 
     async def async_turn_aux_heat_off(self) -> None:
         """Turn auxiliary heater off."""
+        async_create_issue(
+            self.hass,
+            DOMAIN,
+            "migrate_aux_heat",
+            breaks_in_ha_version="2025.4.0",
+            is_fixable=True,
+            is_persistent=True,
+            translation_key="migrate_aux_heat",
+            severity=IssueSeverity.WARNING,
+        )
         self._elk_set(ThermostatMode.HEAT, None)
 
     async def async_set_fan_mode(self, fan_mode: str) -> None:

homeassistant/components/elkm1/strings.json

@@ -189,5 +189,18 @@
       "name": "Sensor zone trigger",
       "description": "Triggers zone."
     }
+  },
+  "issues": {
+    "migrate_aux_heat": {
+      "title": "Migration of Elk-M1 set_aux_heat action",
+      "fix_flow": {
+        "step": {
+          "confirm": {
+            "description": "The Elk-M1 `set_aux_heat` action has been migrated. A new emergency heat switch entity is available for each thermostat.\n\nUpdate any automations to use the new emergency heat switch entity. When this is done, Press submit to fix this issue.",
+            "title": "[%key:component::elkm1::issues::migrate_aux_heat::title%]"
+          }
+        }
+      }
+    }
   }
 }

homeassistant/components/elkm1/switch.py

@@ -4,13 +4,18 @@ from __future__ import annotations
 
 from typing import Any
 
+from elkm1_lib.const import ThermostatMode, ThermostatSetting
+from elkm1_lib.elements import Element
+from elkm1_lib.elk import Elk
 from elkm1_lib.outputs import Output
+from elkm1_lib.thermostats import Thermostat
 
 from homeassistant.components.switch import SwitchEntity
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from . import ElkAttachedEntity, ElkEntity, ElkM1ConfigEntry, create_elk_entities
+from .models import ELKM1Data
 
 
 async def async_setup_entry(
@@ -23,6 +28,9 @@ async def async_setup_entry(
     elk = elk_data.elk
     entities: list[ElkEntity] = []
     create_elk_entities(elk_data, elk.outputs, "output", ElkOutput, entities)
+    create_elk_entities(
+        elk_data, elk.thermostats, "thermostat", ElkThermostatEMHeat, entities
+    )
     async_add_entities(entities)
 
 
@@ -43,3 +51,32 @@ class ElkOutput(ElkAttachedEntity, SwitchEntity):
     async def async_turn_off(self, **kwargs: Any) -> None:
         """Turn off the output."""
         self._element.turn_off()
+
+
+class ElkThermostatEMHeat(ElkEntity, SwitchEntity):
+    """Elk Thermostat emergency heat as switch."""
+
+    _element: Thermostat
+
+    def __init__(self, element: Element, elk: Elk, elk_data: ELKM1Data) -> None:
+        """Initialize the emergency heat switch."""
+        super().__init__(element, elk, elk_data)
+        self._unique_id = f"{self._unique_id}emheat"
+        self._attr_name = f"{element.name} emergency heat"
+
+    @property
+    def is_on(self) -> bool:
+        """Get the current emergency heat status."""
+        return self._element.mode == ThermostatMode.EMERGENCY_HEAT
+
+    def _elk_set(self, mode: ThermostatMode) -> None:
+        """Set the thermostat mode."""
+        self._element.set(ThermostatSetting.MODE, mode)
+
+    async def async_turn_on(self, **kwargs: Any) -> None:
+        """Turn on the output."""
+        self._elk_set(ThermostatMode.EMERGENCY_HEAT)
+
+    async def async_turn_off(self, **kwargs: Any) -> None:
+        """Turn off the output."""
+        self._elk_set(ThermostatMode.EMERGENCY_HEAT)