Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -r3f4105248e6c49ab487ec065f9a4843d72a16a2a -rddcaa054bec161fc48d07b86c3e2550c5bb15fbe
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 3f4105248e6c49ab487ec065f9a4843d72a16a2a)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision ddcaa054bec161fc48d07b86c3e2550c5bb15fbe)
@@ -7,8 +7,8 @@
 *
 * @file    SystemCommMessages.c
 *
-* @author  (last)      Vinayakam Mani
-* @date    (last)      30-Aug-2023
+* @author  (last)      Sean Nash
+* @date    (last)      30-Sep-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  05-Nov-2019
@@ -31,6 +31,7 @@
 #include "ModeStandby.h"
 #include "ModeInitPOST.h"
 #include "OperationModes.h"
+#include "Reservoirs.h"
 #include "RTC.h"
 #include "SampleWater.h"
 #include "SafetyShutdown.h"
@@ -5444,7 +5445,7 @@
     sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
 }
 
-/*************************************************************************
+/*********************************************************************//**
  * @brief
  * The handleSetSwitchesStatusOverrideRequest function handles a
  * request to override the status of a switch in HD.
@@ -5476,7 +5477,7 @@
     sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
 }
 
-/*************************************************************************
+/*********************************************************************//**
  * @brief
  * The handleTestSwitchesPublishIntervalOverrideRequest function handles a
  * request to override the the switches data publish interval.
@@ -8479,4 +8480,36 @@
     sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
 }
 
+/*********************************************************************//**
+ * @brief
+ * The handleTestHDRecirulationPctOverrideRequest function handles a
+ * request to override recirulation percentage.
+ * @details Inputs: none
+ * @details Outputs: message handled
+ * @param message : a pointer to the message to handle
+ * @return none
+ *************************************************************************/
+void handleTestHDRecirulationPctOverrideRequest( MESSAGE_T *message )
+{
+    TEST_OVERRIDE_PAYLOAD_T payload;
+    BOOL result = FALSE;
+
+    // Verify payload length
+    if ( sizeof( TEST_OVERRIDE_PAYLOAD_T ) == message->hdr.payloadLen )
+    {
+        memcpy( &payload, message->payload, sizeof( TEST_OVERRIDE_PAYLOAD_T ) );
+        if ( FALSE == payload.reset )
+        {
+            result = testSetRecirculationLevelPctOverride( payload.state.f32 );
+        }
+        else
+        {
+            result = testResetRecirculationLevelPctOverride();
+        }
+    }
+
+    // Respond to request
+    sendTestAckResponseMsg( (MSG_ID_T)message->hdr.msgID, result );
+}
+
 /**@}*/