diff --git a/caimira/apps/calculator/__init__.py b/caimira/apps/calculator/__init__.py
index 0c3505c2..bf25cee6 100644
--- a/caimira/apps/calculator/__init__.py
+++ b/caimira/apps/calculator/__init__.py
@@ -256,6 +256,10 @@ class ArveData(BaseRequestHandler):
         client_secret = self.settings['arve_client_secret']
         arve_api_key = self.settings['arve_api_key']
 
+        if (client_id == '<undefined>' or client_secret == '<undefined>' or arve_api_key == '<undefined>'):
+            # If the credentials are not defined, we skip the ARVE API connection
+            return self.finish('ARVE API credentials not defined.')
+
         http_client = AsyncHTTPClient()
 
         URL = 'https://arveapi.auth.eu-central-1.amazoncognito.com/oauth2/token'
diff --git a/caimira/apps/calculator/static/js/form.js b/caimira/apps/calculator/static/js/form.js
index 6c0525fa..41536425 100644
--- a/caimira/apps/calculator/static/js/form.js
+++ b/caimira/apps/calculator/static/js/form.js
@@ -312,6 +312,7 @@ function show_sensors_data(url) {
       url: `${$('#url_prefix').data().calculator_prefix}/api/arve/v1/${HOTEL_ID}/${FLOOR_ID}`,
       type: 'GET',
       success: function (result) {
+        if (result.length == 0) return; // If the ARVE credentials were not defined, we don't have a valid result.
         DATA_FROM_SENSORS = result;
         result.map(room => {
           $("#sensors").append(`<option id=${room.RoomId} value=${room.RoomId}>Sensor ${room.RoomId}</option>`);