diff --git a/scripts/reclassify_main_heating.py b/scripts/reclassify_main_heating.py
index a51743aa4..c958458b4 100644
--- a/scripts/reclassify_main_heating.py
+++ b/scripts/reclassify_main_heating.py
@@ -26,13 +26,21 @@ from __future__ import annotations
 
 import argparse
 from collections.abc import Iterable
+from typing import Optional
 
 from sqlalchemy import Connection, text
 
 from domain.epc.property_overrides.main_heating_guard import main_heating_guard
+from domain.epc.property_overrides.main_heating_system_type import (
+    MainHeatingSystemType,
+)
 from scripts.e2e_common import build_engine, load_env
 
 
+def electric_cpsu_for(description: str, main_fuel: Optional[str]) -> Optional[str]:
+    raise NotImplementedError
+
+
 def main_heating_corrections(
     stored: Iterable[tuple[str, str]],
 ) -> dict[str, str]:
diff --git a/tests/scripts/test_reclassify_main_heating.py b/tests/scripts/test_reclassify_main_heating.py
index 12ce4254d..8c172d0c5 100644
--- a/tests/scripts/test_reclassify_main_heating.py
+++ b/tests/scripts/test_reclassify_main_heating.py
@@ -11,7 +11,10 @@ from domain.epc.property_overrides.main_heating_guard import main_heating_guard
 from domain.epc.property_overrides.main_heating_system_type import (
     MainHeatingSystemType,
 )
-from scripts.reclassify_main_heating import main_heating_corrections
+from scripts.reclassify_main_heating import (
+    electric_cpsu_for,
+    main_heating_corrections,
+)
 
 
 def test_garbage_drawer_rows_are_remapped_to_faithful_archetypes() -> None:
@@ -85,6 +88,18 @@ def test_every_guard_target_round_trips_to_a_resolvable_archetype() -> None:
         assert simulation.heating.sap_main_heating_code is not None, description
 
 
+def test_electric_cpsu_is_resolved_from_the_fuel_not_the_description() -> None:
+    # "Boiler: A/C rated CPSU" is identical bar the band — the electric/gas split is
+    # fuel-determined (the pure-string guard can't see it), so the reclassify keys
+    # on the property's main_fuel override: electricity → Electric CPSU (192);
+    # mains gas / unknown → keep Gas CPSU (120). A non-CPSU boiler is ignored here
+    # (the guard handles "NA" electric boilers) — ADR-0045.
+    assert electric_cpsu_for("boiler: a rated cpsu", "electricity") == "Electric CPSU"
+    assert electric_cpsu_for("boiler: c rated cpsu", "mains gas") is None
+    assert electric_cpsu_for("boiler: c rated cpsu", None) is None
+    assert electric_cpsu_for("boiler: a rated na", "electricity") is None
+
+
 def test_already_corrected_rows_need_no_change() -> None:
     # Act / Assert — idempotent.
     assert (