diff --git a/src/devices/boiler.cpp b/src/devices/boiler.cpp
index 8064fe626..7b4311391 100644
--- a/src/devices/boiler.cpp
+++ b/src/devices/boiler.cpp
@@ -3161,7 +3161,7 @@ bool Boiler::set_auxLimit(const char * value, const int8_t id) {
 bool Boiler::set_auxHeaterSource(const char * value, const int8_t id) {
     uint8_t v;
     if (Helpers::value2enum(value, v, FL_(enum_auxHeaterSource))) {
-        write_command(0x491, 0, v ? 1 : 0, 0x491);
+        write_command(0x491, 0, v, 0x491);
         return true;
     }
     return false;
diff --git a/src/emsesp_version.h b/src/emsesp_version.h
index 3a453b8c0..82060ecd8 100644
--- a/src/emsesp_version.h
+++ b/src/emsesp_version.h
@@ -1 +1 @@
-#define EMSESP_APP_VERSION "3.7.3-dev.8"
+#define EMSESP_APP_VERSION "3.7.3-dev.9"