diff --git a/components/truma_inetbox/TrumaEnums.h b/components/truma_inetbox/TrumaEnums.h
index 50c9da1..e33336f 100644
--- a/components/truma_inetbox/TrumaEnums.h
+++ b/components/truma_inetbox/TrumaEnums.h
@@ -141,16 +141,21 @@ enum class ClockSource : u_int8_t {
 
 enum class TRUMA_DEVICE : u_int8_t {
   UNKNOWN = 0x00,
+  
   // Saphir Compact AC
   AIRCON_DEVICE = 0x01,
-  // Combi 4
-  HEATER_COMBI4 = 0x02,
-  // Vario Heat Comfort (non E)
-  HEATER_VARIO = 0x03,
+
   // CP Plus for Combi
   CPPLUS_COMBI = 0x04,
   // CP Plus for Vario Heat
   CPPLUS_VARIO = 0x05,
+
+  // Combi 4
+  HEATER_COMBI4 = 0x02,
+  // Vario Heat Comfort (non E)
+  HEATER_VARIO = 0x03,
+  // Old Truma CP6 (MY 2015)
+  HEATER_CP6 = 0x05,
   // Combi 6 D
   HEATER_COMBI6D = 0x06,
 };
diff --git a/components/truma_inetbox/TrumaiNetBoxApp.cpp b/components/truma_inetbox/TrumaiNetBoxApp.cpp
index b2a09f4..35cc709 100644
--- a/components/truma_inetbox/TrumaiNetBoxApp.cpp
+++ b/components/truma_inetbox/TrumaiNetBoxApp.cpp
@@ -334,16 +334,18 @@ const u_int8_t *TrumaiNetBoxApp::lin_multiframe_recieved(const u_int8_t *message
         ESP_LOGW(TAG, "Unknown information in StatusFrameDevice found. Please report.");
     }
 
-    if (truma_device == TRUMA_DEVICE::HEATER_COMBI4) {
-      this->heater_device_ = TRUMA_DEVICE::HEATER_COMBI4;
-    } else if (truma_device == TRUMA_DEVICE::HEATER_COMBI6D) {
-      this->heater_device_ = TRUMA_DEVICE::HEATER_COMBI6D;
-    } else if (truma_device == TRUMA_DEVICE::HEATER_VARIO) {
-      this->heater_device_ = TRUMA_DEVICE::HEATER_VARIO;
-    }
+    // first submitted device is CP Plus device
+    const auto is_CPPLUSDevice = device.device_id == 0;
 
-    if (truma_device == TRUMA_DEVICE::AIRCON_DEVICE) {
-      this->aircon_device_ = TRUMA_DEVICE::AIRCON_DEVICE;
+    if (!is_CPPLUSDevice) {
+      // Assumption first device is Heater
+      if (device.device_id == 1) {
+        this->heater_device_ = truma_device;
+      }
+      // Assumption second device is Aircon
+      if (device.device_id == 2) {
+        this->aircon_device_ = TRUMA_DEVICE::AIRCON_DEVICE;
+      }
     }
 
     if (device.device_count == 2 && this->heater_device_ != TRUMA_DEVICE::UNKNOWN) {