diff --git a/lib/cartodb/backends/template_maps.js b/lib/cartodb/backends/template_maps.js
index b31e5fb5..9ba54837 100644
--- a/lib/cartodb/backends/template_maps.js
+++ b/lib/cartodb/backends/template_maps.js
@@ -320,24 +320,29 @@ TemplateMaps.prototype.updTemplate = function(owner, tpl_id, template, callback)
 
 
     self._redisCmd('HGET', [ userTemplatesKey, tpl_id ], (err, _currentTemplate) => {
-        assert.ifError(err);
-        if (!_currentTemplate) {
-            throw new Error("Template '" + tpl_id + "' of user '" + owner + "' does not exist");
+        if (err) {
+            return callback(err);
         }
+
+        if (!_currentTemplate) {
+            return callback(new Error(`Template '${tpl_id}' of user '${owner}' does not exist`));
+        }
+
         previousTemplate = _currentTemplate;
         self._redisCmd('HSET', [ userTemplatesKey, templateName, JSON.stringify(template) ], (err, didSetNewField) => {
-            assert.ifError(err);
+            if (err) {
+                return callback(err);
+            }
+
             if (didSetNewField) {
                 debug('New template created on update operation');
             }
 
-            if (!err) {
-                if (self.fingerPrint(JSON.parse(previousTemplate)) !== self.fingerPrint(template)) {
-                    self.emit('update', owner, templateName, template);
-                }
+            if (self.fingerPrint(JSON.parse(previousTemplate)) !== self.fingerPrint(template)) {
+                self.emit('update', owner, templateName, template);
             }
 
-            callback(err, template);
+            return callback(err, template);
         });
     });
 };