diff --git a/stores/bedPressureStore.ts b/stores/bedPressureStore.ts
index 72a94a4..ef52c9f 100644
--- a/stores/bedPressureStore.ts
+++ b/stores/bedPressureStore.ts
@@ -103,13 +103,14 @@ export const useBedPressureStore = create<BedPressureStore>((set, get) => ({
   setSelectedTimespan: (timespan) => set({ selectedTimespan: timespan }),
   
   setActiveAlarms: (alarms) => set({ activeAlarms: alarms }),
-  
-  // Computed values
+    // Computed values
   averageValue: () => {
     const { sensorData } = get();
     const sensors = Object.values(sensorData) as SensorData[];
-    if (sensors.length === 0) return 0;
-    return sensors.reduce((sum: number, sensor: SensorData) => sum + sensor.currentValue, 0) / sensors.length;
+    // Only calculate average for sensors with hardware data
+    const hardwareSensors = sensors.filter(sensor => sensor.source === 'hardware');
+    if (hardwareSensors.length === 0) return 0;
+    return hardwareSensors.reduce((sum: number, sensor: SensorData) => sum + sensor.currentValue, 0) / hardwareSensors.length;
   },
   
   criticalSensors: () => {
@@ -258,20 +259,29 @@ export const useBedPressureStore = create<BedPressureStore>((set, get) => ({
             warningDelayMs,
             warningStartTime
           };
-        });
-
-        set({ 
+        });        set({ 
           sensorData: updated,
-          isConnected: data.connected,
+          isConnected: data.connected || false,
           activeAlarms: alarmManager.getActiveAlarms()
         });
 
         if (newAlerts.length > 0) {
           get().addAlerts(newAlerts);
         }
-      }
-    } catch (error) {
+      } else {        // No sensor data available - set as disconnected
+        const { alarmManager } = get();
+        set({ 
+          isConnected: false,
+          activeAlarms: alarmManager.getActiveAlarms()
+        });
+      }    } catch (error) {
       console.error('Failed to fetch sensor data:', error);
+      // Set as disconnected on error
+      const { alarmManager } = get();
+      set({ 
+        isConnected: false,
+        activeAlarms: alarmManager.getActiveAlarms()
+      });
     }
   },