diff --git a/aircon.sh b/aircon.sh
index ae0f82f..4116dc7 100755
--- a/aircon.sh
+++ b/aircon.sh
@@ -379,6 +379,11 @@ function find_nearby_zones() {  # zone_idx filter1 filter2 ...     filter is:  o
         if [[ $conditions == *noaction* && ${zaction[$zi]} != "n/a" ]]; then
             ok=0
         fi
+        if [[ $conditions == *open* && $constant == ${zname[$zi]} ]]; then
+            # the constant zone never counts as an adjacent 'open' zone, because
+            # if we were to close it, it would just get opened again.
+            ok=0
+        fi
         if [[ $ok -eq 1 ]]; then
             nearbyzones="$nearbyzones $thisone"
         fi