diff --git a/AppInventor/BluetoothHeater.aia b/AppInventor/BluetoothHeater.aia
index e66d51a..a097ecd 100644
Binary files a/AppInventor/BluetoothHeater.aia and b/AppInventor/BluetoothHeater.aia differ
diff --git a/Arduino/SenderTrial2/Protocol.cpp b/Arduino/SenderTrial2/Protocol.cpp
index 5715f15..1c3f4c3 100644
--- a/Arduino/SenderTrial2/Protocol.cpp
+++ b/Arduino/SenderTrial2/Protocol.cpp
@@ -248,7 +248,7 @@ CProtocol::Init(int FrameMode)
     setGlowPlug_Voltage(0);
     setGlowPlug_Current(0);
     Heater.ActualPumpFreq = 0;     // fuel pump freq.: 0.1Hz / digit
-    Heater.ErrorCode = 0;          // 
+    Heater.StoredErrorCode = 0;    // 
     Heater.Unknown1 = 0;           // always 0x00
     Heater.FixedPumpFreq = 23;     // fixed mode frequency set point: 0.1Hz / digit
     Heater.Unknown2 = 100;         // always 0x64  "100 ?"
diff --git a/Arduino/SenderTrial2/Protocol.h b/Arduino/SenderTrial2/Protocol.h
index ccb8c3c..92232a3 100644
--- a/Arduino/SenderTrial2/Protocol.h
+++ b/Arduino/SenderTrial2/Protocol.h
@@ -49,7 +49,7 @@ public:
       unsigned char GlowPlugCurrent_MSB; // 16 bit - big endian MSB  
       unsigned char GlowPlugCurrent_LSB; // 16 bit - big endian LSB : 10mA / digit
       unsigned char ActualPumpFreq;     // fuel pump freq.: 0.1Hz / digit
-      unsigned char ErrorCode;          // 
+      unsigned char StoredErrorCode;    // 
       unsigned char Unknown1;           // always 0x00
       unsigned char FixedPumpFreq;      // fixed mode frequency set point: 0.1Hz / digit
       unsigned char Unknown2;           // always 0x64  "100 ?"
@@ -121,6 +121,8 @@ public:
   void setRunState(unsigned char state) { Heater.RunState = state; };
   unsigned char getErrState() { return Heater.ErrState; };
   void setErrState(unsigned char state) { Heater.ErrState = state; };
+  unsigned char getStoredErrCode() { return Heater.StoredErrorCode; };
+  void setStoredErrCode(unsigned char state) { Heater.StoredErrorCode = state; };
   //
   short getVoltage_Supply();
   void setVoltage_Supply(short voltsx10);
diff --git a/Arduino/SenderTrial2/SenderTrial2.ino b/Arduino/SenderTrial2/SenderTrial2.ino
index 397c491..44a78da 100644
--- a/Arduino/SenderTrial2/SenderTrial2.ino
+++ b/Arduino/SenderTrial2/SenderTrial2.ino
@@ -67,6 +67,7 @@
 #include "pins.h"
 #include "NVStorage.h"
 #include "debugport.h"
+#include "SmartError.h"
 
 #define DEBUG_BTRX
   
@@ -136,6 +137,7 @@ CProtocol OEMCtrlFrame;        // data packet received from heater in response t
 CProtocol HeaterFrame1;        // data packet received from heater in response to OEM controller packet
 CProtocol HeaterFrame2;        // data packet received from heater in response to our packet 
 CProtocol DefaultBTCParams(CProtocol::CtrlMode);  // defines the default parameters, used in case of no OEM controller
+CSmartError SmartError;
 long lastRxTime;        // used to observe inter character delays
 bool hasOEMController = false;
 
@@ -152,10 +154,6 @@ void PrepareTxFrame(const CProtocol& basisFrame, CProtocol& TxFrame, bool isBTCm
 
 void setup() 
 {
-  // initialize serial port to interact with the "blue wire"
-  // 25000 baud, Tx and Rx channels of Chinese heater comms interface:
-  // Tx/Rx data to/from heater, 
-  // Note special baud rate for Chinese heater controllers
   pinMode(Tx2Pin, OUTPUT);
   digitalWrite(Tx2Pin, HIGH);
   pinMode(Rx2Pin, INPUT_PULLUP);
@@ -163,6 +161,10 @@ void setup()
   pinMode(KeyPin, OUTPUT);
   digitalWrite(KeyPin, LOW);
 
+  // initialize serial port to interact with the "blue wire"
+  // 25000 baud, Tx and Rx channels of Chinese heater comms interface:
+  // Tx/Rx data to/from heater, 
+  // Note special baud rate for Chinese heater controllers
 #if defined(__arm__) || defined(__AVR__)
   BlueWireSerial.begin(25000);   
   pinMode(Rx1Pin, INPUT_PULLUP);  // required for MUX to work properly
@@ -181,7 +183,7 @@ void setup()
 
   TxManage.begin(); // ensure Tx enable pin is setup
 
-  // define defaults should heater controller be missing
+  // define defaults should OEM controller be missing
   DefaultBTCParams.setTemperature_Desired(23);
   DefaultBTCParams.setTemperature_Actual(22);
   DefaultBTCParams.Controller.OperatingVoltage = 120;
@@ -310,6 +312,11 @@ void loop()
 
   else if(CommState.is(CommStates::HeaterReport1) ) {
     // received heater frame (after controller message), report
+    
+    // do some monitoring of the heater state variable
+    // if suspicious transitions, introduce a smart error!
+    SmartError.monitor(HeaterFrame1);
+
     // echo heater reponse data to Bluetooth client
     Bluetooth_SendFrame("[HTR]", HeaterFrame1);
 
@@ -343,6 +350,11 @@ void loop()
 
   else if( CommState.is(CommStates::HeaterReport2) ) {
     // received heater frame (after our control message), report
+
+    // do some monitoring of the heater state variable
+    // if suspicious transitions, introduce a smart error!
+    SmartError.monitor(HeaterFrame2);
+
     delay(5);
     if(!hasOEMController) {
       // only convey these frames to Bluetooth when NOT using an OEM controller!
@@ -391,10 +403,12 @@ void Command_Interpret(const char* pLine)
     if(strncmp(pLine, "ON", 2) == 0) {
       TxManage.queueOnRequest();
       DebugPort.println("Heater ON");
+      SmartError.reset();
     }
     else if(strncmp(pLine, "OFF", 3) == 0) {
       TxManage.queueOffRequest();
       DebugPort.println("Heater OFF");
+      SmartError.inhibit();
     }
     else if(strncmp(pLine, "Pmin", 4) == 0) {
       pLine += 4;