diff --git a/datatypes/epc/domain/tests/test_from_site_notes.py b/datatypes/epc/domain/tests/test_from_site_notes.py
index 16ad4f4d8..da5b68768 100644
--- a/datatypes/epc/domain/tests/test_from_site_notes.py
+++ b/datatypes/epc/domain/tests/test_from_site_notes.py
@@ -2669,6 +2669,33 @@ class TestPasHubMainHeatingControlCoding:
         ):
             EpcPropertyDataMapper.from_site_notes(survey)
 
+    def test_room_heater_no_thermostatic_control_maps_to_group6_code(self) -> None:
+        # Arrange — a Table 4e Group 6 room-heater dwelling with the lowest-
+        # control label: "No thermostatic control of room temperature" → 2601
+        # (PCDB `room_heater_systems_controls`, control type 2, +0.3 °C MIT
+        # adjustment) — one step below the already-mapped 2602.
+        from domain.sap10_calculator.rdsap.cert_to_inputs import (
+            _control_type,  # pyright: ignore[reportPrivateUsage]
+        )
+
+        raw = load("pashub_rdsap_site_notes_example1.json")
+        mh = raw["heating_and_hot_water"]["main_heating"]
+        mh["system_type"] = "Room heaters"
+        mh["community_heat_source"] = "Panel, Convector or radiant heaters"
+        mh["fuel"] = "Electricity"
+        mh["product_id"] = 0
+        mh["controls"] = "No thermostatic control of room temperature"
+        survey = from_dict(PasHubRdSapSiteNotes, raw)
+
+        # Act
+        main = EpcPropertyDataMapper.from_site_notes(
+            survey
+        ).sap_heating.main_heating_details[0]
+
+        # Assert
+        assert main.main_heating_control == 2601
+        assert _control_type(main) == 2
+
     def test_heat_network_control_maps_to_group3_code(self) -> None:
         # Arrange — a Table 4e Group 3 heat network (`system_type =
         # "Community heating system"`). Its control label carries a Group 3