Index: firmware/App/Modes/ModeTreatmentParams.c
===================================================================
diff -u -ra7821aff3dc204a060233b0753253ec04d020557 -r1f4d0aead50079c495871c7d0ea1c410186a90c2
--- firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision a7821aff3dc204a060233b0753253ec04d020557)
+++ firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision 1f4d0aead50079c495871c7d0ea1c410186a90c2)
@@ -562,7 +562,7 @@
     U32  dialysateVolume_mL = stagedParams[ TREATMENT_PARAM_DIALYSATE_FLOW ].uInt * \
                               stagedParams[ TREATMENT_PARAM_TREATMENT_DURATION ].uInt;
     F32 heparinVolume_mL = ( stagedParams[ TREATMENT_PARAM_HEPARIN_DISPENSE_RATE ].sFlt * \
-                           ( ( stagedParams[ TREATMENT_PARAM_TREATMENT_DURATION ].uInt - stagedParams[ TREATMENT_PARAM_HEPARIN_PRE_STOP_TIME ].uInt ) / MIN_PER_HOUR ) ) + \
+                           ( (F32)( stagedParams[ TREATMENT_PARAM_TREATMENT_DURATION ].uInt - stagedParams[ TREATMENT_PARAM_HEPARIN_PRE_STOP_TIME ].uInt ) / MIN_PER_HOUR ) ) + \
                              stagedParams[ TREATMENT_PARAM_HEPARIN_BOLUS_VOLUME ].sFlt + SYRINGE_PUMP_PRIME_VOLUME_ML + SYRINGE_PUMP_FILL_VOLUME_OFFSET_ML;
 
     // Check max dialysate volume dependency