diff --git a/src/driver_qheat.cc b/src/driver_qheat.cc
index a3fa204..d9bae6e 100644
--- a/src/driver_qheat.cc
+++ b/src/driver_qheat.cc
@@ -191,11 +191,13 @@ namespace
         it = t->dv_entries.find("0DFF5F");
         if (it != t->dv_entries.end()) {
             DVEntry entry = it->second.second;
-            qdsExtractWalkByField(t, this, entry, 24, 8, "0C05", "total_energy_consumption", Quantity::Energy);
-            qdsExtractWalkByField(t, this, entry, 32, 4, "426C", "last_year_date", Quantity::Text);
-            qdsExtractWalkByField(t, this, entry, 36, 8, "4C05", "last_year_energy_consumption", Quantity::Energy);
-            qdsExtractWalkByField(t, this, entry, 44, 4, "C2086C", "last_month_date", Quantity::Text);
-            qdsExtractWalkByField(t, this, entry, 48, 8, "CC0805", "last_month_energy_consumption", Quantity::Energy);
+            if (entry.value.length() == 53 * 2) {
+                qdsExtractWalkByField(t, this, entry, 24, 8, "0C05", "total_energy_consumption", Quantity::Energy);
+                qdsExtractWalkByField(t, this, entry, 32, 4, "426C", "last_year_date", Quantity::Text);
+                qdsExtractWalkByField(t, this, entry, 36, 8, "4C05", "last_year_energy_consumption", Quantity::Energy);
+                qdsExtractWalkByField(t, this, entry, 44, 4, "C2086C", "last_month_date", Quantity::Text);
+                qdsExtractWalkByField(t, this, entry, 48, 8, "CC0805", "last_month_energy_consumption", Quantity::Energy);
+            }
         }
     }
 }
diff --git a/src/driver_qwater.cc b/src/driver_qwater.cc
index 2148cb7..acaf5aa 100644
--- a/src/driver_qwater.cc
+++ b/src/driver_qwater.cc
@@ -142,6 +142,9 @@ void Driver::processContent(Telegram *t) {
         return;
     }
     DVEntry entry = it->second.second;
+    if (entry.value.length() != 53 * 2) {
+        return;
+    }
     qdsExtractWalkByField(t, this, entry, 24, 8, "0C13", "total", Quantity::Volume);
     qdsExtractWalkByField(t, this, entry, 32, 4, "426C", "due", Quantity::PointInTime);
     qdsExtractWalkByField(t, this, entry, 36, 8, "4C13", "due_date", Quantity::Volume);