diff --git a/WiFiManager.cpp b/WiFiManager.cpp
index f751dae..6782b96 100644
--- a/WiFiManager.cpp
+++ b/WiFiManager.cpp
@@ -86,8 +86,12 @@ void WiFiManagerParameter::setValue(const char *defaultValue, int length) {
   //   // return false; //@todo bail 
   // }
 
-  _length = length;
-  _value  = new char[_length + 1]; 
+  if(_length != length){
+    _length = length;
+    if( _value != nullptr)
+      delete _value;
+    _value  = new char[_length + 1];  
+  }
   memset(_value, 0, _length + 1); // explicit null
   
   if (defaultValue != NULL) {