Index: firmware/App/Modes/ModePreTreat.c
===================================================================
diff -u -rbd4f21cec7b0d25c6a83a53a15220550d4e7bda3 -r5003153f03d3ec0e831d5db6bb4c88fbed1c6a99
--- firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision bd4f21cec7b0d25c6a83a53a15220550d4e7bda3)
+++ firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 5003153f03d3ec0e831d5db6bb4c88fbed1c6a99)
@@ -700,7 +700,7 @@
     patientConnectionConfirm = FALSE;
     treatmentStartRequested = FALSE;
 
-    doorClosedRequired( FALSE, TRUE );
+    doorClosedRequired( TRUE, TRUE );
 
     for ( valve = VDI; valve < NUM_OF_VALVES; ++valve )
     {
@@ -1003,26 +1003,47 @@
 
 /*********************************************************************//**
  * @brief
+ * The handlePatientConnectionDoorOpened function handles the check
+ * for door opened in pre-treatment patient connection
+ * sub-mode.
+ * @details Inputs: none
+ * @details Outputs: doorOpened
+ * @return none
+ *************************************************************************/
+static void handlePatientConnectionDoorOpened( void )
+{
+    // Look for cartridge door to open (indicating user inverting dialyzer)
+    if ( STATE_OPEN == getSwitchStatus( FRONT_DOOR ) )
+    {
+        doorOpened = TRUE;
+        cmdStopDGTrimmerHeater();
+        signalDialInPumpHardStop();
+    }
+    else
+    {
+        setDialInPumpTargetFlowRate( DIP_PATIENT_CONNECTION_FLOW_RATE_ML_MIN, MOTOR_DIR_FORWARD, PUMP_CONTROL_MODE_OPEN_LOOP );
+        cmdStartDGTrimmerHeater();
+    }
+}
+
+/*********************************************************************//**
+ * @brief
  * The handlePatientConnectionWait4UFVolState function handles the wait
  * for ultrafiltration volume setting state of pre-treatment patient connection
  * sub-mode.
  * @details Inputs: setUFVolStatus
- * @details Outputs: setUFVolStatus, doorOpened
+ * @details Outputs: setUFVolStatus
  * @return next patient connection state
  *************************************************************************/
 static HD_PRE_TREATMENT_PAT_CONN_STATE_T handlePatientConnectionWait4UFVolState( void )
 {
     HD_PRE_TREATMENT_PAT_CONN_STATE_T nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_UF_VOL_STATE;
 
-    // Look for cartridge door to open (indicating user inverting dialyzer)
-    if ( STATE_OPEN == getSwitchStatus( FRONT_DOOR ) )
-    {
-        doorOpened = TRUE;
-    }
     // If UF volume set by user, move on to next state
     if ( TRUE == setUFVolStatus )
     {
         setUFVolStatus = FALSE;
+        doorClosedRequired( FALSE, TRUE );
         nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_DLZR_INVERT_STATE;
     }
 
@@ -1035,18 +1056,16 @@
  * for dialyzer invert confirmation state of pre-treatment patient connection
  * sub-mode.
  * @details Inputs: doorOpened
- * @details Outputs: doorOpened
+ * @details Outputs: none
  * @return next patient connection state
  *************************************************************************/
 static HD_PRE_TREATMENT_PAT_CONN_STATE_T handlePatientConnectionWait4DialyzerInvertState( void )
 {
     HD_PRE_TREATMENT_PAT_CONN_STATE_T nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_DLZR_INVERT_STATE;
 
     // Look for cartridge door to open and then close (indicating user inverted dialyzer)
-    if ( STATE_OPEN == getSwitchStatus( FRONT_DOOR ) )
-    {
-        doorOpened = TRUE;
-    }
+    handlePatientConnectionDoorOpened();
+
     if ( ( TRUE == doorOpened ) && ( STATE_CLOSED == getSwitchStatus( FRONT_DOOR ) ) )
     {
         nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_USER_CONFIRM_STATE;
@@ -1068,10 +1087,16 @@
 {
     HD_PRE_TREATMENT_PAT_CONN_STATE_T nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_USER_CONFIRM_STATE;
 
+    // Look for cartridge door to open and then close (indicating user inverted dialyzer)
+    handlePatientConnectionDoorOpened();
+
     if ( TRUE == patientConnectionConfirm )
     {
         doorClosedRequired( TRUE, TRUE );
-        nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_TREATMENT_START_STATE;
+        if ( STATE_CLOSED == getSwitchStatus( FRONT_DOOR ) )
+        {
+            nextState = PRE_TREATMENT_PAT_CONN_WAIT_FOR_TREATMENT_START_STATE;
+        }
     }
 
     return nextState;