diff --git a/lib/cartodb/backends/template_maps.js b/lib/cartodb/backends/template_maps.js
index e2c53e8c..00f0cd2e 100644
--- a/lib/cartodb/backends/template_maps.js
+++ b/lib/cartodb/backends/template_maps.js
@@ -74,7 +74,10 @@ TemplateMaps.prototype._redisCmd = function(redisFunc, redisArgs, callback) {
 
         redisClient[redisFunc.toUpperCase()](...redisArgs, (err, data) => {
             this.redis_pool.release(this.db_signatures, redisClient);
-            return callback(err, data);
+            if (err) {
+                return callback(err);
+            }
+            return callback(null, data);
         });
     });
 };