diff --git a/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/HotWaterHandler.java b/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/HotWaterHandler.java
index b89805f95acee..7ee381d105456 100644
--- a/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/HotWaterHandler.java
+++ b/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/HotWaterHandler.java
@@ -132,7 +132,11 @@ private State getBoostRemainingState() {
             final Integer overrideTimeout = firstChannel.getOverrideTimeoutUnixTime();
 
             if (overrideTimeout != null && !"NONE".equalsIgnoreCase(firstChannel.getOverrideType())) {
-                return new QuantityType<Time>(overrideTimeout - (System.currentTimeMillis() / 1000L), SmartHomeUnits.SECOND).toUnit(SmartHomeUnits.MINUTE);
+                final QuantityType<Time> duration = new QuantityType<Time>(overrideTimeout - (System.currentTimeMillis() / 1000L), SmartHomeUnits.SECOND).toUnit(SmartHomeUnits.MINUTE);
+                if (duration != null)
+                {
+                    return duration;
+                } 
             }
         }
         return new QuantityType<Time>(0, SmartHomeUnits.MINUTE);
diff --git a/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/RoomHandler.java b/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/RoomHandler.java
index e38e0c77a1e71..b1f8d59bb9a98 100644
--- a/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/RoomHandler.java
+++ b/bundles/org.openhab.binding.draytonwiser/src/main/java/org/openhab/binding/draytonwiser/internal/handler/RoomHandler.java
@@ -168,7 +168,11 @@ private State getBoostedState() {
     private State getBoostRemainingState() {
         final Integer overrideTimeout = getData().getOverrideTimeoutUnixTime();
         if (overrideTimeout != null && !"NONE".equalsIgnoreCase(getData().getOverrideType())) {
-            return new QuantityType<Time>(overrideTimeout - (System.currentTimeMillis() / 1000L), SmartHomeUnits.SECOND).toUnit(SmartHomeUnits.MINUTE);
+            final QuantityType<Time> duration = new QuantityType<Time>(overrideTimeout - (System.currentTimeMillis() / 1000L), SmartHomeUnits.SECOND).toUnit(SmartHomeUnits.MINUTE);
+            if (duration != null)
+            {
+                return duration;
+            } 
         }
         return new QuantityType<Time>(0, SmartHomeUnits.MINUTE);
     }