diff --git a/platformio.ini b/platformio.ini
index 2ba16ef..8728a36 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -51,7 +51,7 @@ monitor_speed = 115200
 monitor_filters = direct
 board_build.flash_mode = dio
 board_build.filesystem = littlefs
-version = 1.4.0-rc.20
+version = 1.4.0-rc.21
 
 ; Defaults
 [esp8266_defaults]
diff --git a/src/defines.h b/src/defines.h
index 4a985cf..f7e5718 100644
--- a/src/defines.h
+++ b/src/defines.h
@@ -1,5 +1,5 @@
 #define PROJECT_NAME                "OpenTherm Gateway"
-#define PROJECT_VERSION             "1.4.0-rc.20"
+#define PROJECT_VERSION             "1.4.0-rc.21"
 #define PROJECT_REPO                "https://github.com/Laxilef/OTGateway"
 
 #define EMERGENCY_TIME_TRESHOLD     120000