diff --git a/etl/customers/stonewater/Wave 3 Preparation.py b/etl/customers/stonewater/Wave 3 Preparation.py
index ad35e2d5..dc01ef6f 100644
--- a/etl/customers/stonewater/Wave 3 Preparation.py	
+++ b/etl/customers/stonewater/Wave 3 Preparation.py	
@@ -460,8 +460,11 @@ def extract_epr(pdf_path):
             if data["Existing Secondary Heating System"] == "":
                 data["Existing Secondary Heating Controls"] = ""
             else:
-                data["Existing Secondary Heating Controls"] = re.search(r"Main Heating Controls\s*(.*?)\n",
-                                                                        secondary_text).group(1).strip()
+                # Might not have heating controls on 2nd system
+                secondary_controls_match = re.search(r"Main Heating Controls\s*(.*?)\n", secondary_text)
+                data["Existing Secondary Heating Controls"] = (
+                    secondary_controls_match.group(1).strip() if secondary_controls_match else ""
+                )
             data["Existing Secondary Heating % of Heat"] = int(
                 re.search(r"Percentage of Heat\s*(\d+)\s*%?", secondary_text).group(1)
             )