Index: firmware/App/Controllers/Ultrafiltration.c
===================================================================
diff -u -r520b5b97e2a1a6d7af037e1144f1ffeb39153e3e -r87ee9712a928c58e3fe8b456bce567df0c6a2038
--- firmware/App/Controllers/Ultrafiltration.c	(.../Ultrafiltration.c)	(revision 520b5b97e2a1a6d7af037e1144f1ffeb39153e3e)
+++ firmware/App/Controllers/Ultrafiltration.c	(.../Ultrafiltration.c)	(revision 87ee9712a928c58e3fe8b456bce567df0c6a2038)
@@ -204,8 +204,12 @@
  *************************************************************************/
 static void updateUFRequest( void )
 {
+    F32 qd      = getTDDialysateFlowrate();
+    BOOL bypass = getTDDialyzerBypass();
+
     // update latest UF run/pause request
-    if ( compUFrate > ZERO_RATE )
+    // if qd is zero or dialyzer is bypassed, UF pump should be turn off
+    if ( ( compUFrate > ZERO_RATE ) && ( qd > ZERO_RATE ) && ( FALSE == bypass ) )
     {
         isUltrafiltrationRequested = TRUE;
     }