diff --git a/backend/Funding.py b/backend/Funding.py
index 3c30ba27..1a3b3b67 100644
--- a/backend/Funding.py
+++ b/backend/Funding.py
@@ -419,6 +419,21 @@ class Funding:
         ]:
             return 'Solid Fossil Room Heaters'
 
+        # Handle the case of no heating system - electric heaters assumed
+        if mainheating["has_no_system_present"] or mainheating["has_portable_electric_heaters"]:
+            return 'Electric Room Heaters'
+
+        if not any(mainheating.values()):
+            # This means we have an unknown heating system like 'SAP05:Main-Heating'
+            return 'Electric Room Heaters'
+
+        if mainheating["has_warm_air"] and main_fuel["fuel_type"] == "mains gas":
+            # Treat warm air gas system as a condensing gas boiler
+            if mainheat_energy_eff in ["Good", "Very Good"]:
+                return "Condensing Gas Boiler"
+            else:
+                return "Non Condensing Gas Boiler"
+
         raise ValueError("Invalid pre heating system")
 
     def calculate_partial_project_abs(
diff --git a/backend/tests/test_funding.py b/backend/tests/test_funding.py
index 860dd120..9e46ea9e 100644
--- a/backend/tests/test_funding.py
+++ b/backend/tests/test_funding.py
@@ -1009,6 +1009,8 @@ from tqdm import tqdm
 from etl.epc_clean.epc_attributes.MainheatAttributes import MainHeatAttributes
 from etl.epc_clean.epc_attributes.MainFuelAttributes import MainFuelAttributes
 
+# TODO: Add innovation uplift to private
+
 mock_project_scores_matrix = mock_project_scores_matrix()
 mock_whlg_postcodes = mock_whlg_postcodes()
 mock_partial_scores_matrix = mock_partial_scores_matrix()