diff --git a/libraries/AP_Param/AP_Param.h b/libraries/AP_Param/AP_Param.h
index 8c0cea352e..b7bda5543d 100644
--- a/libraries/AP_Param/AP_Param.h
+++ b/libraries/AP_Param/AP_Param.h
@@ -539,7 +539,7 @@ public:
     /// Combined set and save
     ///
     bool set_and_save(const T &v) {
-        bool force = fabsf(_value - v) < FLT_EPSILON;
+        bool force = fabsf((float)(_value - v)) < FLT_EPSILON;
         set(v);
         return save(force);
     }