diff -r 331e7f700971 -r 495b7eafbf5a main/config.c
--- a/main/config.c	Tue Nov 12 21:57:40 2019 +0100
+++ b/main/config.c	Sun Nov 17 12:58:39 2019 +0100
@@ -91,6 +91,7 @@
             sprintf(units[i].uuid, "c0ffeeee-dead-beef-caf%d-%02x%02x%02x%02x%02x%02x", i & 3,
                         mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);
             sprintf(units[i].alias, "unit%d", (i + 1) & 3);
+	    units[i].pressure_zero = 110;
         }
         write_units();
     } else {