the boiler app now use mqtt instead of relying on an automation on ha side

.gitignore

@@ -4,3 +4,4 @@ __pycache__/
 *.pyc
 logs/
 apps/data/
+secrets.yaml

appdaemon.yaml

@@ -13,6 +13,29 @@ appdaemon:
       token: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJiZThhYWI2ZTlkNmQ0NWU2YTk1ODU5OWJjOWM3MWJkYiIsImlhdCI6MTc3NjEwOTc0NCwiZXhwIjoyMDkxNDY5NzQ0fQ.BorkjFjWlWCZqnUa9-NMUxGsDiupDoRZ3cEgsmeSofM
       cert_verify: True
       ws_timeout: 00:10:00
+    MQTT:
+      type: mqtt
+      namespace: mqtt
+      client_host: 10.0.0.21
+      client_port: 1883
+      client_id: appdaemon_radiator_heating
+      client_user: !secret boiler_mqtt_user
+      client_password: !secret boiler_mqtt_password
+      client_timeout: 30
+      client_topics:
+        - appdaemon/radiator_heating/command/+
+        - appdaemon/radiator_heating/heartbeat
+        - themaplus-condens/bai/SetMode
+        - themaplus-condens/bai/Statenumber
+        - themaplus-condens/bai/FlowTemp
+        - homeassistant/status
+      birth_topic: appdaemon/radiator_heating/connection
+      birth_payload: online
+      birth_retain: true
+      will_topic: appdaemon/radiator_heating/connection
+      will_payload: offline
+      will_retain: true
+      shutdown_payload: offline
 http:
   url: http://0.0.0.0:5050
 admin:

apps/boilerclimate.py

@@ -1,8 +1,4 @@
-"""MQTT-discovered boiler climate; MQTT transport is Home Assistant's service.
-
-Incoming MQTT is forwarded by the companion Home Assistant automation. All
-callbacks run on the app's pinned AppDaemon thread; no broker credentials.
-"""
+"""MQTT-discovered climate using AppDaemon's MQTT plugin and HA sensors."""
 from datetime import datetime, timezone
 import json
 from pathlib import Path
@@ -16,12 +12,22 @@ from logger_interface import LoggerInterface
 class BoilerClimate(hass.Hass, LoggerInterface):
     def initialize(self):
         self.initialize_logger_interface(self.get_ad_api(), ascii_encode=False)
+        self.mqtt_namespace = self.args.get('mqtt_namespace', 'mqtt')
+        if self.AD.plugins.get_plugin_object(self.mqtt_namespace) is None:
+            raise RuntimeError('MQTT plugin missing; configure it and restart AppDaemon')
         self.base = self.args.get('mqtt_topic', 'appdaemon/radiator_heating').rstrip('/')
         self.boiler = self.args.get('boiler_topic', 'themaplus-condens').rstrip('/')
+        self.connection_topic = self.args.get('mqtt_connection_topic', self.base + '/connection')
         self.uid = self.args.get('unique_id', 'appdaemon_radiator_heating')
         self.title = self.args.get('display_name', 'Chauffage radiateurs')
         self.indoor = self.args['indoor_sensor']
-        self.outdoor = self.args['outdoor_sensor']
+        outdoors = self.args.get('outdoor_sensors')
+        if outdoors is None:
+            outdoors = [self.args['outdoor_sensor']]
+        if not isinstance(outdoors, list) or not outdoors or any(not isinstance(e, str) or not e for e in outdoors):
+            raise ValueError('outdoor_sensors must be a non-empty list of entity IDs')
+        self.outdoors = tuple(dict.fromkeys(outdoors))
+        self.selected_outdoor = None
         self.interval = finite(self.args.get('command_interval', 60))
         if not 10 <= self.interval <= 300:
             raise ValueError('command_interval must be between 10 and 300 seconds')
@@ -43,9 +49,10 @@ class BoilerClimate(hass.Hass, LoggerInterface):
         self.sensor_error = None
         self.last_status_time = 0.0
         self._state = None
-        self.listen_event(self._mqtt_event, 'APPDAEMON_BOILER_MQTT')
+        self.listen_event(self._mqtt_event, 'MQTT_MESSAGE', namespace=self.mqtt_namespace)
         self.listen_state(self._sensor_changed, self.indoor, attribute='all')
-        self.listen_state(self._sensor_changed, self.outdoor, attribute='all')
+        for entity in self.outdoors:
+            self.listen_state(self._sensor_changed, entity, attribute='all')
         self._discovery()
         self.run_every(self._tick, 'now', self.interval)
         self._control()
@@ -54,12 +61,15 @@ class BoilerClimate(hass.Hass, LoggerInterface):
     def _publish(self, topic, payload, retain=False):
         if not isinstance(payload, str):
             payload = json.dumps(payload, allow_nan=False, ensure_ascii=False)
-        self.call_service('mqtt/publish', topic=topic, payload=payload, qos=0, retain=retain)
+        self.call_service('mqtt/publish', topic=topic, payload=payload, qos=0,
+                          retain=retain, namespace=self.mqtt_namespace)
 
     def _discovery(self):
         device = dict(identifiers=[self.uid], name=self.title,
                       manufacturer='AppDaemon', model='Weather compensation + room PI')
-        common = dict(device=device, availability_topic=self.base + '/availability')
+        common = dict(device=device, availability=[{'topic': self.base + '/availability'},
+                                                   {'topic': self.connection_topic}],
+                      availability_mode='all')
         config = dict(common, name=None, unique_id=self.uid,
                       default_entity_id='climate.radiator_heating',
                       modes=['off', 'heat'], temperature_unit='C', precision=0.1,
@@ -147,6 +157,11 @@ class BoilerClimate(hass.Hass, LoggerInterface):
 
     def _mqtt_event(self, event, data, kwargs):
         topic, payload = data.get('topic'), data.get('payload', '')
+        if topic is None:
+            if data.get('state') == 'Connected':
+                self._discovery()
+                self._control(force=True)
+            return
         if topic == 'homeassistant/status' and payload == 'online':
             self._discovery()
             self._control()
@@ -201,7 +216,8 @@ class BoilerClimate(hass.Hass, LoggerInterface):
 
     def _attributes(self):
         self._publish(self.base + '/attributes', dict(
-            indoor_sensor=self.indoor, outdoor_sensor=self.outdoor,
+            indoor_sensor=self.indoor, outdoor_sensors=list(self.outdoors),
+            outdoor_sensor=self.selected_outdoor,
             commands_enabled=self.send_commands,
             sensor_error=getattr(self, 'sensor_error', None),
             last_command_at=self.last_command_at, last_c6_echo_at=self.last_echo_at,
@@ -215,16 +231,20 @@ class BoilerClimate(hass.Hass, LoggerInterface):
         indoor = outdoor = None
         result = None
         readings, errors = {}, []
-        for entity in (self.indoor, self.outdoor):
+        sensors = (self.indoor, *self.outdoors)
+        for entity in sensors:
             try:
                 readings[entity] = self._sensor_value(entity)
             except (ValueError, TypeError, KeyError) as exc:
                 errors.append(str(exc))
-        indoor, outdoor = readings.get(self.indoor), readings.get(self.outdoor)
+        indoor = readings.get(self.indoor)
+        self.selected_outdoor = (min(self.outdoors, key=readings.__getitem__)
+                                 if all(entity in readings for entity in self.outdoors) else None)
+        outdoor = readings.get(self.selected_outdoor)
         valid = not errors
         sensor_error = '; '.join(errors) if errors else None
         # Log once per set of failing sensors, not every minute as age increases.
-        signature = tuple((entity, entity in readings) for entity in (self.indoor, self.outdoor))
+        signature = tuple((entity, entity in readings) for entity in sensors)
         previous = getattr(self, '_sensor_fault_signature', None)
         if not valid and signature != previous:
             self.log_error(f'Heating inhibited: sensor fault: {sensor_error}')

apps/boilerwatchdog.py

@@ -0,0 +1,42 @@
+"""Independent AppDaemon worker monitoring the boiler climate heartbeat."""
+import time
+
+import appdaemon.plugins.hass.hassapi as hass
+from logger_interface import LoggerInterface
+from boilerregulator import finite
+
+
+class BoilerWatchdog(hass.Hass, LoggerInterface):
+    def initialize(self):
+        self.initialize_logger_interface(self.get_ad_api(), ascii_encode=False)
+        self.base = self.args.get('mqtt_topic', 'appdaemon/radiator_heating').rstrip('/')
+        self.mqtt_namespace = self.args.get('mqtt_namespace', 'mqtt')
+        self.timeout = finite(self.args.get('heartbeat_timeout', 180))
+        if self.timeout < 60:
+            raise ValueError('heartbeat_timeout must be at least 60 seconds')
+        if self.AD.plugins.get_plugin_object(self.mqtt_namespace) is None:
+            raise RuntimeError('MQTT plugin missing; configure it and restart AppDaemon')
+        self.last_heartbeat = None
+        self.fault = False
+        self.listen_event(self._mqtt_event, 'MQTT_MESSAGE', namespace=self.mqtt_namespace)
+        self.run_every(self._check, 'now', 10)
+        self._check()
+
+    def _mqtt_event(self, event, data, kwargs):
+        if data.get('topic') == self.base + '/heartbeat':
+            self.last_heartbeat = time.monotonic()
+            if self.fault:
+                self.log_info('Boiler climate heartbeat recovered')
+            self.fault = False
+        elif data.get('topic') is None and data.get('state') == 'Connected':
+            self.last_heartbeat = None
+            self.fault = False
+            self._check()
+
+    def _check(self, kwargs=None):
+        if self.last_heartbeat is None or time.monotonic() - self.last_heartbeat >= self.timeout:
+            if not self.fault:
+                self.call_service('mqtt/publish', namespace=self.mqtt_namespace,
+                                  topic=self.base + '/availability', payload='offline', qos=0, retain=True)
+                self.log_warning('Boiler climate unavailable: waiting for a fresh heartbeat')
+                self.fault = True

apps/global/heating.yaml

@@ -224,7 +224,9 @@ radiator_heating:
   display_name: Chauffage radiateurs
   unique_id: appdaemon_radiator_heating
   indoor_sensor: sensor.corridor_temperature
-  outdoor_sensor: sensor.ext_front_temperature
+  outdoor_sensors:
+    - sensor.ext_front_temperature
+    - sensor.ext_back_temperature
   target_temperature: 18
   initial_mode: heat
 
@@ -233,6 +235,8 @@ radiator_heating:
   send_commands: true
   command_interval: 60
   mqtt_topic: appdaemon/radiator_heating
+  mqtt_namespace: mqtt
+  mqtt_connection_topic: appdaemon/radiator_heating/connection
   boiler_topic: themaplus-condens
 
   # Starting values, to tune from observations with radiator circulation enabled.
@@ -247,3 +251,10 @@ radiator_heating:
     max_flow: 50
     overheat: 0.5
     restart_margin: 0.1
+
+radiator_heating_watchdog:
+  module: boilerwatchdog
+  class: BoilerWatchdog
+  mqtt_namespace: mqtt
+  mqtt_topic: appdaemon/radiator_heating
+  heartbeat_timeout: 180

docs/radiator-heating.md

@@ -1,23 +1,36 @@
 # Chauffage radiateurs — AppDaemon et C6
 
 L'app `radiator_heating` expose `climate.radiator_heating` par MQTT Discovery.
-Les publications utilisent le service `mqtt.publish` de Home Assistant, comme
-l'ancienne implémentation de SmartObject. Aucun identifiant MQTT supplémentaire
-ni plugin MQTT AppDaemon n'est nécessaire.
+La version MQTT directe utilise le plugin MQTT d'AppDaemon pour les publications
+et les abonnements. Le plugin Home Assistant sert à lire les thermomètres.
+Les commandes du climate et les retours C6 restent sur les mêmes topics.
+
+## Configuration MQTT
+
+Le plugin `MQTT` est configuré dans `appdaemon.yaml`, namespace `mqtt`.
+Les identifiants du broker sont dans `secrets.yaml` (exclu de Git) et référencés
+par `!secret`. Ils doivent être sauvegardés séparément pour une réinstallation.
+Un redémarrage complet du conteneur/service AppDaemon est nécessaire pour charger
+un nouveau plugin ; le rechargement des apps ne suffit pas.
+
+Le climate et son watchdog exigent ce plugin. Les deux anciennes automatisations
+Home Assistant ont été supprimées après vérification des commandes et de la
+télémétrie en MQTT direct. Aucun relais MQTT dans Home Assistant n'est nécessaire.
 
 ## Fichiers
 
 - `apps/boilerclimate.py` : MQTT Discovery, consigne, mode, mesures et commandes.
+- `apps/boilerwatchdog.py` : surveillance indépendante du heartbeat.
 - `apps/boilerregulator.py` : calcul indépendant de la température d'eau.
-- `apps/global/heating.yaml`, bloc `radiator_heating` : paramètres actifs de l'app.
-- `homeassistant/packages/radiator_heating_mqtt.yaml` : copie des deux
-  automatisations installées via l'API de configuration de Home Assistant.
-  Ne pas inclure aussi cette copie comme package : les automatisations existent
-  déjà dans Home Assistant. Leur modification dans cette copie ne les redéploie pas.
+- `apps/global/heating.yaml`, blocs `radiator_heating` et
+  `radiator_heating_watchdog` : paramètres actifs des deux apps.
+- `appdaemon.yaml`, plugin `MQTT` : connexion broker, abonnements et Last Will.
 
 ## Régulation
 
-Avec S la consigne ambiante, Ti la température du couloir et Te celle de devant :
+Avec S la consigne ambiante, Ti la température du couloir et Te la plus basse
+des températures extérieures (`sensor.ext_front_temperature` et
+`sensor.ext_back_temperature`, configurées dans `outdoor_sensors`) :
 
     courbe = S + pente × (S − Te) + décalage
     correction P = kp × (S − Ti)
@@ -42,7 +55,12 @@ Après arrêt, le redémarrage exige Ti <= S + 0,1 °C et une demande suffisante
 Les gains sont des valeurs initiales à ajuster après les essais de circulation,
 pas des coefficients identifiés pour cette maison.
 
-Les deux capteurs doivent fournir des valeurs finies en °C, entre −40 et 60 °C.
+Le capteur intérieur et les deux capteurs extérieurs doivent fournir des valeurs
+finies en °C, entre −40 et 60 °C. Le minimum extérieur est recalculé à chaque
+mise à jour de l'un des capteurs et à chaque cycle. L'attribut `outdoor_sensors`
+liste les sondes utilisées et `outdoor_sensor` identifie celle sélectionnée.
+Si l'une des sondes est invalide, le chauffage reste inhibé comme auparavant.
+La configuration historique `outdoor_sensor` reste acceptée pour une seule sonde.
 Une température inchangée, même ancienne, reste valide : ces sondes peuvent
 ne publier qu'en cas de changement. Aucun délai sur l'âge de la mesure n'est
 appliqué. Les états indisponibles/inconnus, les valeurs invalides et les unités
@@ -67,11 +85,21 @@ cette app, conserve les accents et le symbole °C.
 - État et diagnostics : `appdaemon/radiator_heating/state` et `/attributes`.
 - Chaudière : `themaplus-condens/bai/SetMode/set`.
 
-L'automatisation de retour transmet les commandes MQTT et les retours chaudière
-à l'événement `APPDAEMON_BOILER_MQTT`, écouté par l'app. Le watchdog marque le
-climate indisponible après trois minutes sans heartbeat. Il ne commande PAS
-la chaudière : il signale l'arrêt de l'app. Configuration et états sont retenus ;
-les commandes utilisateur et chaudière ne doivent jamais être retenues.
+Le plugin transmet les commandes MQTT et les retours chaudière à l'événement
+`MQTT_MESSAGE` du namespace `mqtt`, écouté directement par l'app. Le watchdog
+AppDaemon marque le climate indisponible après trois minutes sans heartbeat
+(vérification toutes les dix secondes). Il ne commande PAS la chaudière.
+Il utilise un worker distinct du climate. Il publie `offline` au démarrage et
+après reconnexion tant qu'aucun heartbeat récent n'est arrivé. Seul le climate
+publie `online`, selon la validité de ses mesures.
+
+La disponibilité MQTT Discovery exige simultanément la disponibilité de l'app
+(`/availability`) et celle de la connexion MQTT (`/connection`). Le plugin
+publie `online` sur `/connection` à la connexion, et le broker publie `offline`
+via le Last Will si cette connexion est perdue. Ce mécanisme ne garantit pas
+une détection immédiate et ne coupe pas le chauffage. Configuration et états
+sont retenus ; les commandes utilisateur et chaudière ne doivent jamais l'être.
+Une reconnexion MQTT republie la découverte et renouvelle la commande.
 
 `SetMode` est renouvelé chaque minute et lors d'un changement de demande.
 Les retours de télémétrie ne renouvellent pas la commande. Un arrêt ordonné

homeassistant/packages/radiator_heating_mqtt.yaml

@@ -1,47 +0,0 @@
-# Installed through HA's automation configuration API. This is the reviewable
-# source copy; do not also include it as a package if the automations exist.
-automation:
-  - id: appdaemon_radiator_heating_bridge
-    alias: AppDaemon - Chauffage radiateurs - Retour MQTT
-    description: Transmet les commandes du climate et les retours C6 à AppDaemon.
-    triggers:
-      - trigger: mqtt
-        topic: appdaemon/radiator_heating/command/+
-      - trigger: mqtt
-        topic: themaplus-condens/bai/SetMode
-      - trigger: mqtt
-        topic: themaplus-condens/bai/Statenumber
-      - trigger: mqtt
-        topic: themaplus-condens/bai/FlowTemp
-      - trigger: mqtt
-        topic: homeassistant/status
-    actions:
-      - event: APPDAEMON_BOILER_MQTT
-        event_data:
-          topic: '{{ trigger.topic }}'
-          payload: '{{ trigger.payload }}'
-    mode: queued
-    max: 50
-  - id: appdaemon_radiator_heating_watchdog
-    alias: AppDaemon - Chauffage radiateurs - Disponibilité
-    description: Marque le climate indisponible après trois minutes sans heartbeat.
-    triggers:
-      - trigger: mqtt
-        topic: appdaemon/radiator_heating/heartbeat
-        id: heartbeat
-      - trigger: homeassistant
-        event: start
-        id: startup
-    actions:
-      - if:
-          - condition: template
-            value_template: "{{ trigger.id == 'heartbeat' }}"
-        then:
-          - delay:
-              minutes: 3
-      - action: mqtt.publish
-        data:
-          topic: appdaemon/radiator_heating/availability
-          payload: offline
-          retain: true
-    mode: restart

tests/test_boilerclimate.py

@@ -11,6 +11,7 @@ sys.path.insert(0, str(Path(__file__).resolve().parents[1] / 'apps'))
 sys.path.insert(0, str(Path(__file__).resolve().parents[1] / 'apps' / 'ad_toolbox'))
 from boilerregulator import BoilerRegulator, setmode
 from boilerclimate import BoilerClimate
+from boilerwatchdog import BoilerWatchdog
 
 
 class RegulatorTests(unittest.TestCase):
@@ -68,8 +69,12 @@ class ClimateTests(unittest.TestCase):
         # Test the actual app callbacks without starting an AppDaemon server.
         app = object.__new__(BoilerClimate)
         app.base, app.boiler = 'appdaemon/test', 'boiler'
+        app.mqtt_namespace = 'mqtt'
+        app.connection_topic = app.base + '/connection'
         app.mode, app.target = 'heat', 18
         app.indoor, app.outdoor = 'sensor.indoor', 'sensor.outdoor'
+        app.outdoors = (app.outdoor,)
+        app.selected_outdoor = None
         app.min_target, app.max_target = 10, 23
         app.interval = 60
         app.controller = BoilerRegulator()
@@ -89,6 +94,39 @@ class ClimateTests(unittest.TestCase):
     def writes(self, app):
         return [c for c in app._publish.call_args_list if c.args[0] == 'boiler/bai/SetMode/set']
 
+    def test_mqtt_transport_uses_plugin_namespace(self):
+        a = self.app()
+        a.call_service = Mock()
+        BoilerClimate._publish(a, 'boiler/bai/SetMode/set', setmode(40, True))
+        call = a.call_service.call_args
+        self.assertEqual(call.args, ('mqtt/publish',))
+        self.assertEqual(call.kwargs['namespace'], 'mqtt')
+        self.assertFalse(call.kwargs['retain'])
+        self.assertEqual(json.loads(call.kwargs['payload']), setmode(40, True))
+
+    def test_discovery_requires_app_and_connection_online(self):
+        a = self.app()
+        a.uid, a.title = 'test_boiler', 'Test boiler'
+        a._discovery()
+        config = a._publish.call_args_list[0].args[1]
+        self.assertNotIn('availability_topic', config)
+        self.assertEqual(config['availability_mode'], 'all')
+        self.assertEqual(config['availability'], [{'topic': a.base + '/availability'},
+                                                   {'topic': a.connection_topic}])
+
+    def test_mqtt_reconnect_renews_discovery_and_command(self):
+        a = self.app()
+        a._discovery = Mock()
+        a._mqtt_event('MQTT_MESSAGE', {'state': 'Connected', 'topic': None}, {})
+        a._discovery.assert_called_once()
+        self.assertEqual(len(self.writes(a)), 1)
+
+    def test_mqtt_disconnect_does_not_publish_or_advance_controller(self):
+        a = self.app()
+        a._mqtt_event('MQTT_MESSAGE', {'state': 'Disconnected', 'topic': None}, {})
+        a._publish.assert_not_called()
+        self.assertEqual(a.previous_time, 1000)
+
     def test_single_change_and_periodic_refresh_only(self):
         a = self.app()
         with patch('boilerclimate.time.monotonic', return_value=1000):
@@ -103,6 +141,34 @@ class ClimateTests(unittest.TestCase):
         for call in self.writes(a):
             self.assertFalse(call.args[2])
 
+    def test_lowest_outdoor_reading_controls_regulation(self):
+        a = self.app()
+        a.target = 23
+        a.outdoors = ('sensor.front', 'sensor.back')
+        readings = {a.indoor: 22.6, 'sensor.front': 30.2, 'sensor.back': 23.7}
+        a._sensor_value = lambda entity: readings[entity]
+        a._control()
+        self.assertEqual(a._state['outdoor'], 23.7)
+        self.assertEqual(a.selected_outdoor, 'sensor.back')
+        self.assertTrue(a._state['heating_requested'])
+        readings['sensor.front'] = 20
+        a._sensor_changed('sensor.front', 'all', None, None, {})
+        self.assertEqual(a._state['outdoor'], 20)
+        self.assertEqual(a.selected_outdoor, 'sensor.front')
+
+    def test_invalid_second_outdoor_sensor_still_inhibits_heat(self):
+        a = self.app()
+        a.outdoors = ('sensor.front', 'sensor.back')
+        def reading(entity):
+            if entity == 'sensor.back':
+                raise ValueError('sensor.back: unavailable')
+            return 18 if entity == a.indoor else 5
+        a._sensor_value = reading
+        a._control()
+        self.assertEqual(self.writes(a)[0].args[1]['disablehc'], 1)
+        self.assertEqual(a._state['reason'], 'invalid_sensor')
+        self.assertIn('sensor.back', a.sensor_error)
+
     def test_invalid_sensor_explicitly_inhibits_heat(self):
         a = self.app()
         a._sensor_value = Mock(side_effect=ValueError('unavailable'))
@@ -265,5 +331,45 @@ class ClimateTests(unittest.TestCase):
         self.assertEqual(a.controller.integral, integral)
 
 
+class WatchdogTests(unittest.TestCase):
+    def app(self):
+        a = object.__new__(BoilerWatchdog)
+        a.base, a.mqtt_namespace, a.timeout = 'appdaemon/test', 'mqtt', 180
+        a.last_heartbeat, a.fault = None, False
+        a.call_service, a.log = Mock(), Mock()
+        a.initialize_logger_interface(a, ascii_encode=False)
+        return a
+
+    def test_missing_heartbeat_publishes_offline_once(self):
+        a = self.app()
+        a._check()
+        a._check()
+        a.call_service.assert_called_once_with('mqtt/publish', namespace='mqtt',
+                                              topic=a.base + '/availability', payload='offline', qos=0, retain=True)
+
+    def test_timeout_and_recovery_do_not_override_sensor_availability(self):
+        a = self.app()
+        with patch('boilerwatchdog.time.monotonic', return_value=1000):
+            a._mqtt_event('', {'topic': a.base + '/heartbeat', 'payload': 'timestamp'}, {})
+        with patch('boilerwatchdog.time.monotonic', return_value=1179):
+            a._check()
+        a.call_service.assert_not_called()
+        with patch('boilerwatchdog.time.monotonic', return_value=1180):
+            a._check()
+        self.assertTrue(a.fault)
+        a.call_service.reset_mock()
+        a._mqtt_event('', {'topic': a.base + '/heartbeat'}, {})
+        self.assertFalse(a.fault)
+        a.call_service.assert_not_called()  # The climate alone decides online/offline for sensor faults.
+
+    def test_reconnection_waits_for_new_heartbeat(self):
+        a = self.app()
+        a.last_heartbeat = 1000
+        a._mqtt_event('', {'topic': None, 'state': 'Connected'}, {})
+        self.assertIsNone(a.last_heartbeat)
+        self.assertTrue(a.fault)
+        self.assertEqual(a.call_service.call_args.kwargs['payload'], 'offline')
+
+
 if __name__ == '__main__':
     unittest.main()