diff --git a/uiserver/webpack.config.js b/uiserver/webpack.config.js
index 80f8941..55bd0e4 100644
--- a/uiserver/webpack.config.js
+++ b/uiserver/webpack.config.js
@@ -22,6 +22,13 @@ try {
     console.error(`[UI Server] Failed to connect to database at ${dbPath}:`, err.message);
 }
 
+// Output bindings: map virtual outputs to physical devices
+// Format: outputChannel -> { device, channel, type }
+const OUTPUT_BINDINGS = {
+    'BigDehumid': { device: 'tapo', channel: 'r0', type: 'switch' },
+    'CO2Valve': { device: 'tapo', channel: 'c', type: 'switch' },
+};
+
 // =============================================
 // WebSocket Server for Agents (port 3962)
 // =============================================
@@ -217,6 +224,11 @@ function handleAgentMessage(ws, message, clientState, clientId) {
             ws.send(JSON.stringify({ type: 'auth', success: true, devicePrefix: keyInfo.device_prefix, name: keyInfo.name }));
             break;
 
+        case 'pong':
+            // Keepalive from agent - just update timestamp
+            clientState.lastPong = Date.now();
+            break;
+
         case 'data':
             if (!clientState.authenticated) {
                 ws.send(JSON.stringify({ type: 'error', error: 'Not authenticated' }));
@@ -266,6 +278,45 @@ function sendCommandToDevicePrefix(devicePrefix, command) {
     return sent > 0;
 }
 
+// Periodic sync: push non-zero output states to agents every 60s
+function syncOutputStates() {
+    if (!db) return;
+
+    try {
+        // Get current output values
+        const stmt = db.prepare(`
+            SELECT channel, value FROM output_events 
+            WHERE id IN (SELECT MAX(id) FROM output_events GROUP BY channel)
+        `);
+        const rows = stmt.all();
+
+        for (const row of rows) {
+            // Only sync non-zero values
+            if (row.value > 0) {
+                const binding = OUTPUT_BINDINGS[row.channel];
+                if (binding) {
+                    const success = sendCommandToDevicePrefix(`${binding.device}:`, {
+                        device: binding.channel,
+                        action: 'set_state',
+                        value: 1
+                    });
+
+                    if (!success) {
+                        console.error(`[Sync] ERROR: Cannot deliver 'on' command for ${row.channel} -> ${binding.device}:${binding.channel} (no agent connected)`);
+                    }
+                }
+            }
+        }
+    } catch (err) {
+        console.error('[Sync] Error syncing output states:', err.message);
+    }
+}
+
+// Start output state sync interval (every 60s)
+setInterval(syncOutputStates, 60000);
+// Also sync immediately on startup after a short delay
+setTimeout(syncOutputStates, 5000);
+
 // Start the WebSocket server
 const agentWss = createAgentWebSocketServer();
 
@@ -515,13 +566,6 @@ module.exports = {
                 }
             });
 
-            // Output bindings: map virtual outputs to physical devices
-            // Format: outputChannel -> { device, channel, type }
-            const OUTPUT_BINDINGS = {
-                'BigDehumid': { device: 'tapo', channel: 'r0', type: 'switch' },
-                'CO2Valve': { device: 'tapo', channel: 'c', type: 'switch' },
-            };
-
             // GET /api/outputs/commands - Get desired states for bound devices
             // Agents poll this to get commands. Returns { "device:channel": { state: 0|1 } }
             app.get('/api/outputs/commands', (req, res) => {