diff --git a/src/omotes_simulator_core/adapter/transforms/esdl_asset_mappers/pipe_mapper.py b/src/omotes_simulator_core/adapter/transforms/esdl_asset_mappers/pipe_mapper.py
index 3ab12336..041ea135 100644
--- a/src/omotes_simulator_core/adapter/transforms/esdl_asset_mappers/pipe_mapper.py
+++ b/src/omotes_simulator_core/adapter/transforms/esdl_asset_mappers/pipe_mapper.py
@@ -13,6 +13,7 @@
 #  You should have received a copy of the GNU General Public License
 #  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 """Module containing the Esdl to Pipe asset mapper class."""
+
 import logging
 from typing import Any
 
@@ -102,26 +103,25 @@ def _get_diameter(esdl_asset: EsdlAssetObject) -> float:
         the insulation schedule must be provided; in this case, it is assumed to be 1.
 
         """
-        inner_diameter = esdl_asset.get_property("innerDiameter", 0)
-        dn_diameter = esdl_asset.get_property("diameter", None)
         # Use default schedule since schedule is not a valid ESDL Pipe attribute
         # TODO add method to get schedule from esdl if it becomes available.
         schedule = PIPE_DEFAULTS.default_schedule
 
-        if inner_diameter == 0:
-            if dn_diameter is not None:
-                esdl_object = EsdlAssetPipeMapper._get_esdl_object_from_edr(
-                    dn_diameter.name, schedule
-                )
-                logger.info(
-                    f"Property innerDiameter is not set for: {esdl_asset.get_name()}, "
-                    f"Schedule S1 is assumed for retrieval of pipe diameter from EDR list."
-                )
-                return float(esdl_object.innerDiameter)
-            else:
-                return PIPE_DEFAULTS.diameter
-        else:
-            return float(inner_diameter)
+        if esdl_asset.esdl_asset.eIsSet("innerDiameter"):
+            inner_diameter = float(esdl_asset.get_property("innerDiameter", PIPE_DEFAULTS.diameter))
+            if inner_diameter != 0:
+                return inner_diameter
+
+        dn_diameter = esdl_asset.get_property("diameter", PIPE_DEFAULTS.diameter)
+        if dn_diameter is PIPE_DEFAULTS.diameter:
+            return PIPE_DEFAULTS.diameter
+
+        esdl_object = EsdlAssetPipeMapper._get_esdl_object_from_edr(dn_diameter.name, schedule)
+        logger.info(
+            f"Property innerDiameter is not set for: {esdl_asset.get_name()}, "
+            f"Schedule S1 is assumed for retrieval of pipe inner diameter from EDR list."
+        )
+        return float(esdl_object.innerDiameter)
 
     @staticmethod
     def _get_esdl_object_from_edr(
diff --git a/unit_test/adapters/transforms/esdl_asset_mappers/test_esdl_asset_pipe_mapper.py b/unit_test/adapters/transforms/esdl_asset_mappers/test_esdl_asset_pipe_mapper.py
index f167aa13..6167e29b 100644
--- a/unit_test/adapters/transforms/esdl_asset_mappers/test_esdl_asset_pipe_mapper.py
+++ b/unit_test/adapters/transforms/esdl_asset_mappers/test_esdl_asset_pipe_mapper.py
@@ -14,6 +14,7 @@
 #  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 """Test pipe mapper."""
+
 import typing
 import unittest
 from pathlib import Path
@@ -138,6 +139,7 @@ def mock_get_property(key, default=None):
             return default
 
         esdl_asset_mock.get_property = mock_get_property
+        esdl_asset_mock.esdl_asset.eIsSet.side_effect = lambda key: key == "innerDiameter"
 
         # Act
         diameter = EsdlAssetPipeMapper._get_diameter(esdl_asset_mock)
@@ -160,6 +162,7 @@ def mock_get_property(key, default=None):
             return default
 
         esdl_asset_mock.get_property = mock_get_property
+        esdl_asset_mock.esdl_asset.eIsSet.side_effect = lambda key: key == "diameter"
         edr_object_mock = Mock()
         edr_object_mock.innerDiameter = 0.42
 
@@ -172,6 +175,37 @@ def mock_get_property(key, default=None):
             # Assert
             self.assertEqual(diameter, 0.42)
 
+    def test_get_diameter_with_inner_diameter_zero_uses_edr(self):
+        """Falls back to EDR when innerDiameter is set to 0 but a DN diameter is provided."""
+        # Arrange
+        esdl_asset_mock = Mock()
+        dn_mock = Mock()
+        dn_mock.name = "DN125"
+
+        def mock_get_property(key, default=None):
+            if key == "innerDiameter":
+                return 0
+            if key == "diameter":
+                return dn_mock
+            return default
+
+        esdl_asset_mock.get_property = mock_get_property
+        esdl_asset_mock.esdl_asset.eIsSet.side_effect = lambda key: key in (
+            "innerDiameter",
+            "diameter",
+        )
+        edr_object_mock = Mock()
+        edr_object_mock.innerDiameter = 0.1273
+
+        with patch.object(
+            EsdlAssetPipeMapper, "_get_esdl_object_from_edr", return_value=edr_object_mock
+        ):
+            # Act
+            diameter = EsdlAssetPipeMapper._get_diameter(esdl_asset_mock)
+
+            # Assert
+            self.assertEqual(diameter, 0.1273)
+
     def test_get_diameter_default_when_none_provided(self):
         """Returns default diameter when both innerDiameter is 0 and diameter is None."""
         # Arrange
@@ -180,11 +214,10 @@ def test_get_diameter_default_when_none_provided(self):
         def mock_get_property(key, default=None):
             if key == "innerDiameter":
                 return 0
-            if key == "diameter":
-                return None
             return default
 
         esdl_asset_mock.get_property = mock_get_property
+        esdl_asset_mock.esdl_asset.eIsSet.return_value = False
 
         # Act
         diameter = EsdlAssetPipeMapper._get_diameter(esdl_asset_mock)
@@ -224,6 +257,7 @@ def mock_get_property(key, default=None):
             return default
 
         esdl_asset_mock.get_property = mock_get_property
+        esdl_asset_mock.esdl_asset.eIsSet.side_effect = lambda key: key == "diameter"
         edr_object_mock = Mock()
         edr_object_mock.innerDiameter = 0.08