diff --git a/src/system.js b/src/system.js
index 620255695..da03105c0 100644
--- a/src/system.js
+++ b/src/system.js
@@ -151,7 +151,7 @@ async function checkDiskSpace() {
 
 async function getSwapSize() {
     const swaps = await getSwaps();
-    return Object.keys(swaps).map(n => swaps[n].size).reduce((acc, cur) => acc + cur);
+    return Object.keys(swaps).map(n => swaps[n].size).reduce((acc, cur) => acc + cur, 0);
 }
 
 async function getMemory() {