diff --git a/etc/kayobe/kolla/config/prometheus/system.rules b/etc/kayobe/kolla/config/prometheus/system.rules
index fe3a2b9ac..ffc7d25a3 100644
--- a/etc/kayobe/kolla/config/prometheus/system.rules
+++ b/etc/kayobe/kolla/config/prometheus/system.rules
@@ -34,7 +34,7 @@ groups:
       description: "OOM kill detected"
 
   - alert: Overheating
-    expr: node_hwmon_temp_celsius >= 85
+    expr: node_hwmon_temp_celsius >= node_hwmon_temp_max_celsius
     for: 1m
     labels:
       severity: warning