diff --git a/thermostat/importers.py b/thermostat/importers.py
index 6e4967a..8a4520b 100644
--- a/thermostat/importers.py
+++ b/thermostat/importers.py
@@ -442,7 +442,7 @@ def _calculate_heat_runtime(df, thermostat_id, heat_type, heat_stage, hourly_ind
             return
 
         if has_multi_stage_heating(heat_stage):
-            warnings.warn("Multi-stage cooling isn't supported (yet)")
+            warnings.warn("Multi-stage heating isn't supported (yet)")
             return
 
         if has_two_stage_heating(heat_stage):