diff --git a/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/ConventionalWinter.mo b/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/ConventionalWinter.mo
index 4690d10c77f..1fd8c073893 100644
--- a/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/ConventionalWinter.mo
+++ b/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/ConventionalWinter.mo
@@ -4,6 +4,7 @@ model ConventionalWinter
   extends Buildings.Air.Systems.SingleZone.VAV.Examples.OptimalStart.ConventionalSpring;
 
   annotation (experiment(
+      StartTime=0,
       StopTime=604800,
       Tolerance=1e-06),
       __Dymola_Commands(file="modelica://Buildings/Resources/Scripts/Dymola/Air/Systems/SingleZone/VAV/Examples/OptimalStart/ConventionalWinter.mos"
diff --git a/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/Guideline36Winter.mo b/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/Guideline36Winter.mo
index e528890802f..57ab2c21be5 100644
--- a/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/Guideline36Winter.mo
+++ b/Buildings/Air/Systems/SingleZone/VAV/Examples/OptimalStart/Guideline36Winter.mo
@@ -4,6 +4,7 @@ model Guideline36Winter
   extends Buildings.Air.Systems.SingleZone.VAV.Examples.OptimalStart.Guideline36Spring;
 
   annotation (experiment(
+      StartTime=0,
       StopTime=604800,
       Tolerance=1e-06),
       __Dymola_Commands(file="modelica://Buildings/Resources/Scripts/Dymola/Air/Systems/SingleZone/VAV/Examples/OptimalStart/Guideline36Winter.mos"