diff --git a/datatypes/epc/domain/tests/test_from_site_notes.py b/datatypes/epc/domain/tests/test_from_site_notes.py
index c6647ca82..07786b566 100644
--- a/datatypes/epc/domain/tests/test_from_site_notes.py
+++ b/datatypes/epc/domain/tests/test_from_site_notes.py
@@ -1100,6 +1100,24 @@ class TestPasHubMainHeatingControlCoding:
         ):
             EpcPropertyDataMapper.from_site_notes(survey)
 
+    def test_shared_control_label_on_non_boiler_system_strict_raises(self) -> None:
+        # Arrange — the boiler table's codes are SAP 10.2 Table 4e Group 1 (21xx);
+        # the *same* control label appears in every system group under a different
+        # 2xxx code (e.g. "Programmer, room thermostat and TRVs" is 2106 on a
+        # boiler but 2210/2306/… on a heat pump / heat network). Resolving the
+        # label alone would silently give a non-boiler dwelling the boiler code,
+        # so a non-boiler system_type must strict-raise, naming the system.
+        raw = load("pashub_rdsap_site_notes_example1.json")
+        raw["heating_and_hot_water"]["main_heating"]["system_type"] = "Heat pump"
+        raw["heating_and_hot_water"]["main_heating"][
+            "controls"
+        ] = "Programmer, room thermostat and TRVs"
+        survey = from_dict(PasHubRdSapSiteNotes, raw)
+
+        # Act / Assert
+        with pytest.raises(UnmappedPasHubLabel, match="Heat pump"):
+            EpcPropertyDataMapper.from_site_notes(survey)
+
 
 class TestPasHubUnmappedHeatEmitter:
     """A PasHub survey whose surveyed main-heating emitter label the mapper does