diff --git a/src/core/emsdevice.cpp b/src/core/emsdevice.cpp
index 20d338584..d5c18839d 100644
--- a/src/core/emsdevice.cpp
+++ b/src/core/emsdevice.cpp
@@ -368,7 +368,7 @@ void EMSdevice::fetch_values() {
 
     for (const auto & tf : telegram_functions_) {
         if (tf.fetch_) {
-            read_command(tf.telegram_type_id_);
+            read_command(tf.telegram_type_id_, 0, tf.length_);
         }
     }
 }
@@ -547,8 +547,8 @@ void EMSdevice::show_mqtt_handlers(uuid::console::Shell & shell) const {
 }
 
 // register a callback function for a specific telegram type
-void EMSdevice::register_telegram_type(const uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, const process_function_p f) {
-    telegram_functions_.emplace_back(telegram_type_id, telegram_type_name, fetch, false, f);
+void EMSdevice::register_telegram_type(const uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, const process_function_p f, uint8_t length) {
+    telegram_functions_.emplace_back(telegram_type_id, telegram_type_name, fetch, false, length, f);
 }
 
 // add to device value library, also know now as a "device entity"
diff --git a/src/core/emsdevice.h b/src/core/emsdevice.h
index f584e9b58..366f76a2e 100644
--- a/src/core/emsdevice.h
+++ b/src/core/emsdevice.h
@@ -259,7 +259,7 @@ class EMSdevice {
     void setCustomizationEntity(const std::string & entity_id);
     void getCustomizationEntities(std::vector<std::string> & entity_ids);
 
-    void register_telegram_type(const uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, const process_function_p cb);
+    void register_telegram_type(const uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, const process_function_p cb, uint8_t length = 0);
     bool handle_telegram(std::shared_ptr<const Telegram> telegram);
 
     std::string get_value_uom(const std::string & shortname) const;
@@ -555,13 +555,15 @@ class EMSdevice {
         const char *             telegram_type_name_; // e.g. RC20Message
         bool                     fetch_;              // if this type_id be queried automatically
         bool                     received_;
+        uint8_t                  length_;
         const process_function_p process_function_;
 
-        TelegramFunction(uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, bool received, const process_function_p process_function)
+        TelegramFunction(uint16_t telegram_type_id, const char * telegram_type_name, bool fetch, bool received, uint8_t length, const process_function_p process_function)
             : telegram_type_id_(telegram_type_id)
             , telegram_type_name_(telegram_type_name)
             , fetch_(fetch)
             , received_(received)
+            , length_(length)
             , process_function_(process_function) {
         }
     };
diff --git a/src/devices/boiler.cpp b/src/devices/boiler.cpp
index 0f8e60970..66c9505d2 100644
--- a/src/devices/boiler.cpp
+++ b/src/devices/boiler.cpp
@@ -83,7 +83,7 @@ Boiler::Boiler(uint8_t device_type, int8_t device_id, uint8_t product_id, const
 
         register_telegram_type(0x492, "HpHeaterConfig", true, MAKE_PF_CB(process_HpHeaterConfig));
         register_telegram_type(0x488, "HPValve", true, MAKE_PF_CB(process_HpValve));
-        register_telegram_type(0x484, "HPSilentMode", true, MAKE_PF_CB(process_HpSilentMode));
+        register_telegram_type(0x484, "HPSilentMode", true, MAKE_PF_CB(process_HpSilentMode), 65);
         register_telegram_type(0x48B, "HPPumps", true, MAKE_PF_CB(process_HpPumps));
         register_telegram_type(0x491, "HPAdditionalHeater", true, MAKE_PF_CB(process_HpAdditionalHeater));
         register_telegram_type(0x499, "HPDhwSettings", true, MAKE_PF_CB(process_HpDhwSettings));