diff --git a/Arduino/Afterburner/Afterburner.ino b/Arduino/Afterburner/Afterburner.ino
index b033a45..57a18d0 100644
--- a/Arduino/Afterburner/Afterburner.ino
+++ b/Arduino/Afterburner/Afterburner.ino
@@ -99,6 +99,7 @@
 #include "src/Utility/helpers.h"
 #include "src/Utility/NVStorage.h"
 #include "src/Utility/DebugPort.h"
+#include "src/Utility/macros.h"
 #include "src/Utility/UtilClasses.h"
 #include "src/Utility/BTC_JSON.h"
 #include "src/Utility/BTC_GPIO.h"
@@ -446,7 +447,11 @@ void setup() {
   FilteredSamples.Fan.setRounding(10);
   FilteredSamples.Fan.setAlpha(0.7);
   FilteredSamples.AmbientTemp.reset(-100.0);
-
+  FilteredSamples.FastipVolts.setRounding(0.1);
+  FilteredSamples.FastipVolts.setAlpha(0.7);
+  FilteredSamples.FastGlowAmps.setRounding(0.01);
+  FilteredSamples.FastGlowAmps.setAlpha(0.7);
+  
   RTC_Store.begin();
   FuelGauge.init(RTC_Store.getFuelGauge());
 //  demandDegC = RTC_Store.getDesiredTemp();
@@ -796,6 +801,9 @@ void loop()
         updateFilteredData();
         FuelGauge.Integrate(HeaterFrame2.getPump_Actual());
       }
+      if(INBOUNDS(HeaterFrame2.getRunState(), 1, 5)) {  // check for Low Voltage Cutout
+        SmartError.checkVolts(FilteredSamples.FastipVolts.getValue(), FilteredSamples.FastGlowAmps.getValue());
+      }
       updateJSONclients(bReportJSONData);
       CommState.set(CommStates::Idle);
       NVstore.doSave();   // now is a good time to store to the NV storage, well away from any blue wire activity
@@ -822,7 +830,7 @@ void manageCyclicMode()
   const sCyclicThermostat& cyclic = NVstore.getUserSettings().cyclic;
   if(cyclic.Stop && RTC_Store.getCyclicEngaged()) {   // cyclic mode enabled, and user has started heater
     int stopDeltaT = cyclic.Stop + 1;  // bump up by 1 degree - no point invoking at 1 deg over!
-    float deltaT = FilteredSamples.AmbientTemp.getValue() - getDemandDegC();
+    float deltaT = getTemperatureSensor() - getDemandDegC();
 //    DebugPort.printf("Cyclic=%d bUserOn=%d deltaT=%d\r\n", cyclic, bUserON, deltaT);
 
     // ensure we cancel user ON mode if heater throws an error
@@ -883,8 +891,10 @@ bool validateFrame(const CProtocol& frame, const char* name)
 
 void requestOn()
 {
-  heaterOn();
-  RTC_Store.setCyclicEngaged(true);    // for cyclic mode
+  if(SmartError.checkVolts(FilteredSamples.FastipVolts.getValue(), FilteredSamples.FastGlowAmps.getValue())) {
+    heaterOn();
+    RTC_Store.setCyclicEngaged(true);    // for cyclic mode
+  }
 }
 
 void requestOff()
@@ -1041,7 +1051,7 @@ float getTemperatureDesired()
 
 float getTemperatureSensor()
 {
-  return FilteredSamples.AmbientTemp.getValue();
+  return FilteredSamples.AmbientTemp.getValue() + NVstore.getHeaterTuning().tempOfs;
 }
 
 void  setPumpMin(float val)
@@ -1449,12 +1459,15 @@ void simulateGPIOin(uint8_t newKey)
   GPIOin.simulateKey(newKey);
 }
 
-float getBatteryVoltage()
+float getBatteryVoltage(bool fast)
 {
 #ifdef RAW_SAMPLES
   return getHeaterInfo().getBattVoltage();
 #else
-  return FilteredSamples.ipVolts.getValue();
+  if(fast)
+    return FilteredSamples.FastipVolts.getValue();
+  else
+    return FilteredSamples.ipVolts.getValue();
 #endif
 }
 
@@ -1491,6 +1504,8 @@ void updateFilteredData()
   FilteredSamples.GlowVolts.update(HeaterFrame2.getGlowPlug_Voltage());
   FilteredSamples.GlowAmps.update(HeaterFrame2.getGlowPlug_Current());
   FilteredSamples.Fan.update(HeaterFrame2.getFan_Actual());
+  FilteredSamples.FastipVolts.update(HeaterFrame2.getVoltage_Supply());
+  FilteredSamples.FastGlowAmps.update(HeaterFrame2.getGlowPlug_Current());
 }
 
 int sysUptime()
diff --git a/README.md b/README.md
index afa12d8..690a7e8 100644
--- a/README.md
+++ b/README.md
@@ -51,15 +51,15 @@ Working so far:
     Web browser upload new binary to controller (AP or STA mode)
     Direct discovery and download of updates from internet server (STA mode)
 * Factory default menu option
+* "Fuel gauge" - Integrates pump frequency, assumes a repeatable dose of fuel per pump stroke.
+* Low voltage cut out, definable threshold - auto adjusts for cable voltage drop during start
+* Temperature probe offset to correct adverse readings.
  
 
 To be implemented 
 --------------------------
 * 433MHz Rx stream, 433MHz Tx stream connections. This would allow external timer units for example, or analogue temperature demand (which is still only 1 degree resolution with standard heater thermostat).
-* Low voltage cut out
-* Temperature probe offset or mapping to correct adverse readings.
 * MQTT pub/sub 
-* "fuel gauge" - Integrate pump frequency, assuming a repeatable dose of fuel per pump cycle...
 * Regular Hot Burn cycle (DPF mode!)
 * Hour meter - run time, glow time
 * list under construction.....
diff --git a/icons/BatteryIcon.bmp b/icons/BatteryIcon.bmp
index 5cf003a..fdd9ec9 100644
Binary files a/icons/BatteryIcon.bmp and b/icons/BatteryIcon.bmp differ
diff --git a/icons/FuelIcon.bmp b/icons/FuelIcon.bmp
index a590cf3..cd72aec 100644
Binary files a/icons/FuelIcon.bmp and b/icons/FuelIcon.bmp differ
diff --git a/icons/FuelIconSmall.bmp b/icons/FuelIconSmall.bmp
new file mode 100644
index 0000000..5dba1b2
Binary files /dev/null and b/icons/FuelIconSmall.bmp differ
diff --git a/icons/MiniThermo.bmp b/icons/MiniThermo.bmp
new file mode 100644
index 0000000..91aa1d4
Binary files /dev/null and b/icons/MiniThermo.bmp differ
diff --git a/src/Afterburner/Afterburner.cpp b/src/Afterburner/Afterburner.cpp
index b033a45..57a18d0 100644
--- a/src/Afterburner/Afterburner.cpp
+++ b/src/Afterburner/Afterburner.cpp
@@ -99,6 +99,7 @@
 #include "src/Utility/helpers.h"
 #include "src/Utility/NVStorage.h"
 #include "src/Utility/DebugPort.h"
+#include "src/Utility/macros.h"
 #include "src/Utility/UtilClasses.h"
 #include "src/Utility/BTC_JSON.h"
 #include "src/Utility/BTC_GPIO.h"
@@ -446,7 +447,11 @@ void setup() {
   FilteredSamples.Fan.setRounding(10);
   FilteredSamples.Fan.setAlpha(0.7);
   FilteredSamples.AmbientTemp.reset(-100.0);
-
+  FilteredSamples.FastipVolts.setRounding(0.1);
+  FilteredSamples.FastipVolts.setAlpha(0.7);
+  FilteredSamples.FastGlowAmps.setRounding(0.01);
+  FilteredSamples.FastGlowAmps.setAlpha(0.7);
+  
   RTC_Store.begin();
   FuelGauge.init(RTC_Store.getFuelGauge());
 //  demandDegC = RTC_Store.getDesiredTemp();
@@ -796,6 +801,9 @@ void loop()
         updateFilteredData();
         FuelGauge.Integrate(HeaterFrame2.getPump_Actual());
       }
+      if(INBOUNDS(HeaterFrame2.getRunState(), 1, 5)) {  // check for Low Voltage Cutout
+        SmartError.checkVolts(FilteredSamples.FastipVolts.getValue(), FilteredSamples.FastGlowAmps.getValue());
+      }
       updateJSONclients(bReportJSONData);
       CommState.set(CommStates::Idle);
       NVstore.doSave();   // now is a good time to store to the NV storage, well away from any blue wire activity
@@ -822,7 +830,7 @@ void manageCyclicMode()
   const sCyclicThermostat& cyclic = NVstore.getUserSettings().cyclic;
   if(cyclic.Stop && RTC_Store.getCyclicEngaged()) {   // cyclic mode enabled, and user has started heater
     int stopDeltaT = cyclic.Stop + 1;  // bump up by 1 degree - no point invoking at 1 deg over!
-    float deltaT = FilteredSamples.AmbientTemp.getValue() - getDemandDegC();
+    float deltaT = getTemperatureSensor() - getDemandDegC();
 //    DebugPort.printf("Cyclic=%d bUserOn=%d deltaT=%d\r\n", cyclic, bUserON, deltaT);
 
     // ensure we cancel user ON mode if heater throws an error
@@ -883,8 +891,10 @@ bool validateFrame(const CProtocol& frame, const char* name)
 
 void requestOn()
 {
-  heaterOn();
-  RTC_Store.setCyclicEngaged(true);    // for cyclic mode
+  if(SmartError.checkVolts(FilteredSamples.FastipVolts.getValue(), FilteredSamples.FastGlowAmps.getValue())) {
+    heaterOn();
+    RTC_Store.setCyclicEngaged(true);    // for cyclic mode
+  }
 }
 
 void requestOff()
@@ -1041,7 +1051,7 @@ float getTemperatureDesired()
 
 float getTemperatureSensor()
 {
-  return FilteredSamples.AmbientTemp.getValue();
+  return FilteredSamples.AmbientTemp.getValue() + NVstore.getHeaterTuning().tempOfs;
 }
 
 void  setPumpMin(float val)
@@ -1449,12 +1459,15 @@ void simulateGPIOin(uint8_t newKey)
   GPIOin.simulateKey(newKey);
 }
 
-float getBatteryVoltage()
+float getBatteryVoltage(bool fast)
 {
 #ifdef RAW_SAMPLES
   return getHeaterInfo().getBattVoltage();
 #else
-  return FilteredSamples.ipVolts.getValue();
+  if(fast)
+    return FilteredSamples.FastipVolts.getValue();
+  else
+    return FilteredSamples.ipVolts.getValue();
 #endif
 }
 
@@ -1491,6 +1504,8 @@ void updateFilteredData()
   FilteredSamples.GlowVolts.update(HeaterFrame2.getGlowPlug_Voltage());
   FilteredSamples.GlowAmps.update(HeaterFrame2.getGlowPlug_Current());
   FilteredSamples.Fan.update(HeaterFrame2.getFan_Actual());
+  FilteredSamples.FastipVolts.update(HeaterFrame2.getVoltage_Supply());
+  FilteredSamples.FastGlowAmps.update(HeaterFrame2.getGlowPlug_Current());
 }
 
 int sysUptime()
diff --git a/src/Afterburner/src/OLED/BasicScreen.cpp b/src/Afterburner/src/OLED/BasicScreen.cpp
index 9538c88..d643eb3 100644
--- a/src/Afterburner/src/OLED/BasicScreen.cpp
+++ b/src/Afterburner/src/OLED/BasicScreen.cpp
@@ -50,7 +50,7 @@ CBasicScreen::CBasicScreen(C128x64_OLED& display, CScreenManager& mgr) : CScreen
 bool 
 CBasicScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
 
   char msg[20];
   int xPos, yPos;
diff --git a/src/Afterburner/src/OLED/ClockScreen.cpp b/src/Afterburner/src/OLED/ClockScreen.cpp
index a16c40e..9fcb39a 100644
--- a/src/Afterburner/src/OLED/ClockScreen.cpp
+++ b/src/Afterburner/src/OLED/ClockScreen.cpp
@@ -43,10 +43,11 @@ CClockScreen::CClockScreen(C128x64_OLED& display, CScreenManager& mgr) : CScreen
 }
 
 
+
 bool 
 CClockScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
   
   const BTCDateTime& now = Clock.get();
 
diff --git a/src/Afterburner/src/OLED/DetailedScreen.cpp b/src/Afterburner/src/OLED/DetailedScreen.cpp
index 414ff42..4532436 100644
--- a/src/Afterburner/src/OLED/DetailedScreen.cpp
+++ b/src/Afterburner/src/OLED/DetailedScreen.cpp
@@ -82,7 +82,7 @@ CDetailedScreen::CDetailedScreen(C128x64_OLED& display, CScreenManager& mgr) : C
 bool 
 CDetailedScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
 
   int runstate = getHeaterInfo().getRunStateEx();
   int errstate = getHeaterInfo().getErrState(); 
@@ -133,7 +133,7 @@ CDetailedScreen::show()
   }
 
   if(!bGlowActive) {
-    showBowser(FuelGauge.Used_ml());
+    showBowser(FuelGauge.Used_mL());
   }
   showRunState(runstate, errstate);
   return true;
diff --git a/src/Afterburner/src/OLED/FuelCalScreen.h b/src/Afterburner/src/OLED/FuelCalScreen.h
new file mode 100644
index 0000000..8bbe878
--- /dev/null
+++ b/src/Afterburner/src/OLED/FuelCalScreen.h
@@ -0,0 +1,48 @@
+/*
+ * This file is part of the "bluetoothheater" distribution 
+ * (https://gitlab.com/mrjones.id.au/bluetoothheater) 
+ *
+ * Copyright (C) 2018  Ray Jones <ray@mrjones.id.au>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ * 
+ */
+
+#ifndef __FUELCALSCREEN_H__
+#define __FUELCALSCREEN_H__
+
+#include <stdint.h>
+#include "PasswordScreen.h"
+
+class C128x64_OLED;
+class CScreenManager;
+
+class CFuelCalScreen : public CPasswordScreen
+{
+  int _rowSel;
+  void _adjust(int dir);
+  float _mlPerStroke;
+  float _tOfs;
+  uint8_t _LVC;
+  int _animateCount;
+  void _initUI();
+public:
+  CFuelCalScreen(C128x64_OLED& display, CScreenManager& mgr);
+  bool show();
+  bool animate();
+  bool keyHandler(uint8_t event);
+  void onSelect();
+};
+
+#endif
diff --git a/src/Afterburner/src/OLED/FuelMixtureScreen.cpp b/src/Afterburner/src/OLED/FuelMixtureScreen.cpp
index 0f12062..8347ffe 100644
--- a/src/Afterburner/src/OLED/FuelMixtureScreen.cpp
+++ b/src/Afterburner/src/OLED/FuelMixtureScreen.cpp
@@ -34,6 +34,7 @@
 #include "../Utility/DebugPort.h"
 #include "../Utility/macros.h"
 #include "../Protocol/Protocol.h"
+#include "fonts/Icons.h"
 
 
 CFuelMixtureScreen::CFuelMixtureScreen(C128x64_OLED& display, CScreenManager& mgr) : CPasswordScreen(display, mgr) 
@@ -47,6 +48,12 @@ CFuelMixtureScreen::onSelect()
   CPasswordScreen::onSelect();
   _initUI();
   
+  _load();
+}
+
+void
+CFuelMixtureScreen::_load()
+{
   adjPump[0] = getHeaterInfo().getPump_Min();
   adjPump[1] = getHeaterInfo().getPump_Max();
   adjFan[0] = getHeaterInfo().getFan_Min();
@@ -58,6 +65,7 @@ CFuelMixtureScreen::_initUI()
 {
   _rowSel = 0;
   _colSel = 0;
+  _animateCount = 0;
 }
 
 bool 
@@ -67,34 +75,40 @@ CFuelMixtureScreen::show()
   int xPos, yPos;
   const int col3 = _display.width() - border;
 
-  _display.clearDisplay();
+  _display.fillRect(70, 0, 58, 64, BLACK);    // scrub variables
+  _display.fillRect(0, 50, 128, 14, BLACK);   // scrub footer
 
   if(!CPasswordScreen::show()) {
+
     switch(_rowSel) {
       case 0:
       case 1:
       case 2:
       case 3:
       case 4:
+        if(_animateCount == -1) {
+          _animateCount = 0;
+          _display.clearDisplay();
+        }
         // Pump Minimum adjustment
         yPos = border + 36;
-        _printMenuText(80, yPos, "Min", false, eRightJustify);
-        sprintf(str, "%.1f", adjPump[0]); 
+        _printMenuText(65, yPos, "Min", false, eRightJustify);
+        sprintf(str, "%.1f Hz", adjPump[0]); 
         _printMenuText(col3, yPos, str, _rowSel == 1, eRightJustify);
         // Pump Maximum adjustment
         yPos = border + 24;
-        _printMenuText(80, yPos, "Pump Hz Max", false, eRightJustify);
-        sprintf(str, "%.1f", adjPump[1]);
+        _printMenuText(65, yPos, "Max", false, eRightJustify);
+        sprintf(str, "%.1f Hz", adjPump[1]);
         _printMenuText(col3, yPos, str, _rowSel == 2, eRightJustify);
         // Fan Minimum adjustment
         yPos = border + 12;
-        _printMenuText(80, yPos, "Min", false, eRightJustify);
-        sprintf(str, "%d", adjFan[0]);
+        _printMenuText(65, yPos, "Min", false, eRightJustify);
+        sprintf(str, "%d RPM", adjFan[0]);
         _printMenuText(col3, yPos, str, _rowSel == 3, eRightJustify);
         // Fan Maximum adjustment
         yPos = border;
-        _printMenuText(80, yPos, "Fan RPM Max", false, eRightJustify);
-        sprintf(str, "%d", adjFan[1]);
+        _printMenuText(65, yPos, "Max", false, eRightJustify);
+        sprintf(str, "%d RPM", adjFan[1]);
         _printMenuText(col3, yPos, str, _rowSel == 4, eRightJustify);
         // navigation line
         yPos = 53;
@@ -128,6 +142,29 @@ CFuelMixtureScreen::show()
   return true;
 }
 
+bool 
+CFuelMixtureScreen::animate()
+{
+  if(_animateCount >= 0) {
+
+    int xPos = 20;
+    int yPos = 5;
+    int yFuel = 30;
+    _display.fillRect(xPos, yPos, FanIcon1Info.width, FanIcon1Info.height, BLACK);
+    _display.fillRect(xPos+5, yFuel, FuelIconInfo.width, FuelIconInfo.height + 4, BLACK);
+    _drawBitmap(xPos+5, yFuel+_animateCount, FuelIconInfo);
+    switch(_animateCount) {
+      case 0: _drawBitmap(xPos, yPos, FanIcon1Info); break;
+      case 1: _drawBitmap(xPos, yPos, FanIcon2Info); break;
+      case 2: _drawBitmap(xPos, yPos, FanIcon3Info); break;
+      case 3: _drawBitmap(xPos, yPos, FanIcon4Info); break;
+    }
+
+    _animateCount++;
+    WRAPUPPERLIMIT(_animateCount, 3, 0);
+  }
+  return true; 
+}
 
 bool 
 CFuelMixtureScreen::keyHandler(uint8_t event)
@@ -143,6 +180,8 @@ CFuelMixtureScreen::keyHandler(uint8_t event)
         case 2:
         case 3:
         case 4:
+          _animateCount = -1;
+          _display.clearDisplay();
           _rowSel = 5;  // enter save confirm mode
           break;
         case 5:
@@ -204,6 +243,8 @@ CFuelMixtureScreen::keyHandler(uint8_t event)
             UPPERLIMIT(_rowSel, 4);
             break;
           case 5:
+            _display.clearDisplay();
+            _animateCount = -1;
             _showStoringMessage();
             setPumpMin(adjPump[0]);
             setPumpMax(adjPump[1]);
@@ -233,7 +274,10 @@ CFuelMixtureScreen::keyHandler(uint8_t event)
     _ScreenManager.reqUpdate();
   }
 
-  
+  if(_rowSel == 0) {
+    _load();  // dispose of any changes, re-obtain current settings 
+  }
+
   if(event & keyRepeat) {
     switch(_rowSel) {
       case 1:
diff --git a/src/Afterburner/src/OLED/FuelMixtureScreen.h b/src/Afterburner/src/OLED/FuelMixtureScreen.h
index 44d5ea1..25f563f 100644
--- a/src/Afterburner/src/OLED/FuelMixtureScreen.h
+++ b/src/Afterburner/src/OLED/FuelMixtureScreen.h
@@ -33,12 +33,15 @@ class CFuelMixtureScreen : public CPasswordScreen {
   uint16_t adjFan[2];
   int  _rowSel;
   int  _colSel;
+  int _animateCount;
   void _adjustSetting(int dir);
   void _initUI();
+  void _load();
 
 public:
   CFuelMixtureScreen(C128x64_OLED& display, CScreenManager& mgr);
   bool show();
+  bool animate();
   bool keyHandler(uint8_t event);
   void onSelect();
 };
diff --git a/src/Afterburner/src/OLED/GPIOScreen.cpp b/src/Afterburner/src/OLED/GPIOScreen.cpp
index f75d904..f160c95 100644
--- a/src/Afterburner/src/OLED/GPIOScreen.cpp
+++ b/src/Afterburner/src/OLED/GPIOScreen.cpp
@@ -291,12 +291,6 @@ CGPIOInfoScreen::CGPIOInfoScreen(C128x64_OLED& display, CScreenManager& mgr) : C
   _keyRepeatCount = -1;
 }
 
-void 
-CGPIOInfoScreen::onSelect()
-{
-  CScreenHeader::onSelect();
-}
-
 void
 CGPIOInfoScreen::_initUI()
 {
@@ -305,7 +299,7 @@ CGPIOInfoScreen::_initUI()
 bool 
 CGPIOInfoScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
   char msg[16];
 
   _display.writeFillRect(49, 18, 30, 12, WHITE);
diff --git a/src/Afterburner/src/OLED/GPIOScreen.h b/src/Afterburner/src/OLED/GPIOScreen.h
index fdcceb5..7ad720f 100644
--- a/src/Afterburner/src/OLED/GPIOScreen.h
+++ b/src/Afterburner/src/OLED/GPIOScreen.h
@@ -53,7 +53,6 @@ public:
   CGPIOInfoScreen(C128x64_OLED& display, CScreenManager& mgr);
   bool show();
   bool keyHandler(uint8_t event);
-  void onSelect();
 };
 
 #endif
diff --git a/src/Afterburner/src/OLED/HeaterSettingsScreen.cpp b/src/Afterburner/src/OLED/HeaterSettingsScreen.cpp
index f481b7d..f2c1c50 100644
--- a/src/Afterburner/src/OLED/HeaterSettingsScreen.cpp
+++ b/src/Afterburner/src/OLED/HeaterSettingsScreen.cpp
@@ -21,11 +21,13 @@
 
 #include "128x64OLED.h"
 #include "HeaterSettingsScreen.h"
+#include "FuelCalScreen.h"
 #include "KeyPad.h"
 #include "../Utility/helpers.h"
 #include "../Utility/macros.h"
 #include "../Utility/NVStorage.h"
 #include "../Protocol/Protocol.h"
+#include "fonts/Icons.h"
 
 ///////////////////////////////////////////////////////////////////////////
 //
@@ -264,6 +266,8 @@ CFuelCalScreen::CFuelCalScreen(C128x64_OLED& display, CScreenManager& mgr) : CPa
 {
   _initUI();
   _mlPerStroke = 0.02;
+  _LVC = 115;
+  _tOfs = 0;
 }
 
 void 
@@ -272,6 +276,8 @@ CFuelCalScreen::onSelect()
   CPasswordScreen::onSelect();
   _initUI();
   _mlPerStroke = NVstore.getHeaterTuning().pumpCal;
+  _LVC = NVstore.getHeaterTuning().lowVolts;
+  _tOfs = NVstore.getHeaterTuning().tempOfs;
 }
 
 void
@@ -285,7 +291,10 @@ bool
 CFuelCalScreen::show()
 {
   char msg[20];
-  _display.clearDisplay();
+  const int col = 90;
+
+  _display.fillRect(0, 50, 128, 14, BLACK);
+  _display.fillRect(col-border, Line3-border, 128-(col-1), 64-Line3-border, BLACK);
 
   if(!CPasswordScreen::show()) {  // for showing "saving settings"
 
@@ -295,13 +304,31 @@ CFuelCalScreen::show()
       _printMenuText(_display.xCentre(), 43, "confirm save", false, eCentreJustify);
     }
     else {
-      int col = 80;
-      _printInverted(_display.xCentre(), 0, " Fuel Calibration ", true, eCentreJustify);
-      _printMenuText(col, Line1, "ml / stroke:", false, eRightJustify);
+      if(_animateCount < 0) {
+        _display.clearDisplay();
+        _animateCount = 0;
+      }
+      _printInverted(_display.xCentre(), 0, " Special Features ", true, eCentreJustify);
+      // fuel calibration
+      int yPos = Line1;
+      _printMenuText(col, yPos, "mL/stroke : ", false, eRightJustify);
       sprintf(msg, "%.03f", _mlPerStroke);
-      _printMenuText(col+1, Line1, msg, _rowSel == 1);
+      _printMenuText(col, yPos, msg, _rowSel == 1);
+      // low voltage cutout
+      yPos = Line2;
+      _printMenuText(col, yPos, "L.V.C. < ", false, eRightJustify);
+      if(_LVC) 
+        sprintf(msg, "%.1fV", float(_LVC) * 0.1);
+      else
+        strcpy(msg, "OFF");
+      _printMenuText(col, yPos, msg, _rowSel == 2);
+      // temp offset
+      yPos = Line3;
+      _printMenuText(col, yPos, "\367C offset : ", false, eRightJustify);
+      sprintf(msg, "%+.1f", _tOfs);
+      _printMenuText(col, yPos, msg, _rowSel == 3);
       // navigation line
-      int yPos = 53;
+      yPos = 53;
       int xPos = _display.xCentre();
 
       switch(_rowSel) {
@@ -324,43 +351,44 @@ CFuelCalScreen::show()
 bool 
 CFuelCalScreen::animate()
 { 
-/*  char msg[16];
+  if(_animateCount >= 0) {
+    switch(_animateCount) {
+      case 0:
+        _display.fillRect(0, Line3-4, BatteryIconInfo.width, 40, BLACK);
+        _drawBitmap(6, Line1-3, FuelIconSmallInfo);
+        _drawBitmap(0, Line2-1 , BatteryIconInfo);
+        _drawBitmap(5, Line3-4, miniThermoIconInfo);
+        break;
+      case 2:
+        _display.fillRect(6, Line1-3, FuelIconSmallInfo.width, FuelIconSmallInfo.height, BLACK); // scrub prior drip
+        _drawBitmap(6, Line1-2, FuelIconSmallInfo);    // drip fuel
+        _display.fillRect(BatteryIconInfo.width - 4, Line2+2, 2, 5, BLACK);   // deplete battery
+        _display.fillRect(7, Line3+2, 2, 2, WHITE);    // grow thermometer
+        break;
+      case 4:
+        _display.fillRect(6, Line1-2, FuelIconSmallInfo.width, FuelIconSmallInfo.height, BLACK); // scrub prior drip
+        _drawBitmap(6, Line1-1, FuelIconSmallInfo);    // drip fuel
+        _display.fillRect(BatteryIconInfo.width - 7, Line2+2, 2, 5, BLACK);   // deplete battery
+        _display.fillRect(7, Line3+1, 2, 1, WHITE);    // grow thermometer
+        break;
+      case 6:
+        _display.fillRect(6, Line1-1, FuelIconSmallInfo.width, FuelIconSmallInfo.height, BLACK); // scrub prior drip
+        _drawBitmap(6, Line1, FuelIconSmallInfo);    // drip fuel
+        _display.fillRect(BatteryIconInfo.width - 10, Line2+2, 2, 5, BLACK);   // deplete battery
+        _display.fillRect(7, Line3, 2, 1, WHITE);    // grow thermometer
+        break;
+      case 8:
+        _display.fillRect(6, Line1, FuelIconSmallInfo.width, FuelIconSmallInfo.height, BLACK); // scrub prior drip
+        _drawBitmap(6, Line1+1, FuelIconSmallInfo);    // drip fuel
+        _display.fillRect(BatteryIconInfo.width - 13, Line2+2, 2, 5, BLACK);   // deplete battery
+        _display.fillRect(7, Line3-1, 2, 1, WHITE);    // grow thermometer
+        break;
+    }
 
-  if(isPasswordBusy() || (_rowSel == 4)) {  // Password screen activity
-    _printMenuText(Column, Line2, "    ");
-    _printMenuText(Column, Line1, "    ");
-    if(_rowSel == 4)
-      _printMenuText(_display.xCentre(), 43, "Confirm save", false, eCentreJustify);
-  }
-  else {
     _animateCount++;
     WRAPUPPERLIMIT(_animateCount, 9, 0);
+  }
 
-    if(_rowSel == 1) {
-      _display.drawRect(Column-border, Line1-border, 34, 8+2*border, BLACK);
-      _display.drawRoundRect(Column-border, Line1-border, 34, 8+2*border, radius, WHITE);
-    }
-    else {
-      _printMenuText(Column, Line1, "     ");
-    }
-
-    if(_animateCount < 4) 
-      sprintf(msg, "PF-%d ", _glowDrive);
-    else
-      sprintf(msg, "(%dW)", plugPowers[_glowDrive-1]);
-    _printMenuText(Column, Line1, msg);
-
-    int xPos = Column;
-    _printMenuText(xPos, Line2, "    ", _rowSel == 2); // erase, but create selection loop
-    if(_animateCount < 4) {
-      sprintf(msg, "SN-%d", _fanSensor);
-      _printMenuText(Column, Line2, msg);
-    }
-    else {
-      sprintf(msg, "(\365%d)", _fanSensor);  // \365 is division character
-      _printMenuText(xPos, Line2, msg);  
-    }
-  }*/
   return true;
 }
 
@@ -370,6 +398,15 @@ CFuelCalScreen::keyHandler(uint8_t event)
 {
   sHeaterTuning tuning;
 
+  if(event & keyRepeat) {
+    if(event & key_Left) {
+      _adjust(-1);
+    } 
+    if(event & key_Right) {
+      _adjust(+1);
+    } 
+  }
+
   if(event & keyPressed) {
     // press LEFT to select previous screen
     if(event & key_Left) {
@@ -418,9 +455,13 @@ CFuelCalScreen::keyHandler(uint8_t event)
           UPPERLIMIT(_rowSel, 3);
           break;
         case 4:    // confirmed save
+          _display.clearDisplay();
+          _animateCount = -1;
           _showStoringMessage();
           tuning = NVstore.getHeaterTuning();
           tuning.pumpCal = _mlPerStroke;
+          tuning.lowVolts = _LVC;
+          tuning.tempOfs = _tOfs;
           NVstore.setHeaterTuning(tuning);
           saveNV();
           _rowSel = 0;
@@ -436,6 +477,8 @@ CFuelCalScreen::keyHandler(uint8_t event)
         case 1:
         case 2:
         case 3:
+          _animateCount = -1;
+          _display.clearDisplay();          
           _rowSel = 4;
           break;
       }
@@ -452,10 +495,34 @@ CFuelCalScreen::_adjust(int dir)
   switch(_rowSel) {
     case 1:   
       _mlPerStroke += dir * 0.001;
+      BOUNDSLIMIT(_mlPerStroke, 0.001, 1);
       break;
-    case 2:   
+    case 2:
+      if(_LVC == 0) {
+        if(NVstore.getHeaterTuning().sysVoltage == 120)
+          _LVC = dir > 0 ? 115 : 0;
+        else 
+          _LVC = dir > 0 ? 230 : 0;
+      }
+      else {
+        _LVC += dir;
+        if(NVstore.getHeaterTuning().sysVoltage == 120) {
+          if(_LVC < 100)
+            _LVC = 0;
+          else 
+            UPPERLIMIT(_LVC, 125);
+        }
+        else {
+          if(_LVC < 200)
+            _LVC = 0;
+          else 
+            UPPERLIMIT(_LVC, 250);
+        }
+      }
       break;
-    case 3:   
+    case 3:
+      _tOfs += dir * 0.1;
+      BOUNDSLIMIT(_tOfs, -10, 10);
       break;
   }
 }
diff --git a/src/Afterburner/src/OLED/HeaterSettingsScreen.h b/src/Afterburner/src/OLED/HeaterSettingsScreen.h
index fd1b6b4..36f439a 100644
--- a/src/Afterburner/src/OLED/HeaterSettingsScreen.h
+++ b/src/Afterburner/src/OLED/HeaterSettingsScreen.h
@@ -45,19 +45,4 @@ public:
   void onSelect();
 };
 
-class CFuelCalScreen : public CPasswordScreen
-{
-  int _rowSel;
-  void _adjust(int dir);
-  float _mlPerStroke;
-  int _animateCount;
-  void _initUI();
-public:
-  CFuelCalScreen(C128x64_OLED& display, CScreenManager& mgr);
-  bool show();
-  bool animate();
-  bool keyHandler(uint8_t event);
-  void onSelect();
-};
-
 #endif
diff --git a/src/Afterburner/src/OLED/InheritSettingsScreen.cpp b/src/Afterburner/src/OLED/InheritSettingsScreen.cpp
index d68e8f2..be5fb5a 100644
--- a/src/Afterburner/src/OLED/InheritSettingsScreen.cpp
+++ b/src/Afterburner/src/OLED/InheritSettingsScreen.cpp
@@ -57,7 +57,7 @@ CInheritSettingsScreen::_initUI()
 bool 
 CInheritSettingsScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
 
   _display.writeFillRect(0, 16, 96, 12, WHITE);
   _printInverted(3, 18, "Inherit Settings", true);
diff --git a/src/Afterburner/src/OLED/PasswordScreen.cpp b/src/Afterburner/src/OLED/PasswordScreen.cpp
index 8bb808d..f1d890d 100644
--- a/src/Afterburner/src/OLED/PasswordScreen.cpp
+++ b/src/Afterburner/src/OLED/PasswordScreen.cpp
@@ -41,6 +41,7 @@ CPasswordScreen::CPasswordScreen(C128x64_OLED& display, CScreenManager& mgr) : C
 void
 CPasswordScreen::onSelect()
 {
+  CScreenHeader::onSelect();
   _initUI();
 }
 
diff --git a/src/Afterburner/src/OLED/PrimingScreen.cpp b/src/Afterburner/src/OLED/PrimingScreen.cpp
index 9a2f48f..0a0674f 100644
--- a/src/Afterburner/src/OLED/PrimingScreen.cpp
+++ b/src/Afterburner/src/OLED/PrimingScreen.cpp
@@ -46,6 +46,7 @@ CPrimingScreen::CPrimingScreen(C128x64_OLED& display, CScreenManager& mgr) : CSc
 void
 CPrimingScreen::onSelect()
 {
+  CScreenHeader::onSelect();
   _stopPump();
   _initUI();
 }
@@ -69,7 +70,7 @@ CPrimingScreen::_initUI()
 bool 
 CPrimingScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
   
   CRect extents;
 
@@ -200,7 +201,7 @@ CPrimingScreen::show()
   }
   else {
     char msg[16];
-    sprintf(msg, "%.02fL", FuelGauge.Used_ml() * 0.001);
+    sprintf(msg, "%.02fL", FuelGauge.Used_mL() * 0.001);
     _printMenuText(loc.xPos+1, midline+3, msg);
   }
 
diff --git a/src/Afterburner/src/OLED/Screen.cpp b/src/Afterburner/src/OLED/Screen.cpp
index a2b40ba..5bc8d52 100644
--- a/src/Afterburner/src/OLED/Screen.cpp
+++ b/src/Afterburner/src/OLED/Screen.cpp
@@ -63,6 +63,7 @@ CScreen::show()
 void 
 CScreen::onSelect()
 {
+  _display.clearDisplay();
 }
 
 void
diff --git a/src/Afterburner/src/OLED/ScreenHeader.cpp b/src/Afterburner/src/OLED/ScreenHeader.cpp
index 5f08d95..2d5c602 100644
--- a/src/Afterburner/src/OLED/ScreenHeader.cpp
+++ b/src/Afterburner/src/OLED/ScreenHeader.cpp
@@ -31,6 +31,8 @@
 #include "fonts/Icons.h"
 #include "fonts/MiniFont.h"
 #include "../RTC/TimerManager.h"
+#include "../Protocol/SmartError.h"
+#include "../Utility/DataFilter.h"
 
 
 #define MINIFONT miniFontInfo
@@ -65,9 +67,15 @@ CScreenHeader::CScreenHeader(C128x64_OLED& disp, CScreenManager& mgr) : CScreen(
 }
 
 bool 
-CScreenHeader::show()
+CScreenHeader::show(bool erase)
 {
-  _display.clearDisplay();
+  if(erase)
+    _display.clearDisplay();                  // erase everything
+  else {
+    _display.fillRect(0, 17, 128, 47, BLACK); // only erase below the header
+    _display.fillRect(119, 0, 9, 17, BLACK); // erase top of body thermo
+    _display.fillRect(0, 0, 9, 17, BLACK);   // erase top of ambient thermo
+  }
 
   // standard header items
   // Bluetooth
@@ -75,8 +83,7 @@ CScreenHeader::show()
 
   // WiFi icon is updated in animate()
 
-  // battery
-  showBatteryIcon(getBatteryVoltage());
+  // Battery is updated in animate
 
   // clock
   showTime();
@@ -104,7 +111,9 @@ CScreenHeader::animate()
   // animate timer icon, 
   // inserting an update icon if new firmware available from internet web server
   _animateCount++;
-  WRAPUPPERLIMIT(_animateCount, 10, 0);
+  _batteryCount++;
+  WRAPUPPERLIMIT(_animateCount, 9, 0);
+  WRAPUPPERLIMIT(_batteryCount, 5, 0);
   if(isUpdateAvailable(true)) {
     int xPos = X_TIMER_ICON - 3;   
     int yPos = Y_TIMER_ICON;
@@ -122,7 +131,22 @@ CScreenHeader::animate()
     }
   }
   else {
+    int xPos = X_BATT_ICON;   
+    int yPos = Y_BATT_ICON;
     showTimers();
+    switch(_batteryCount) {
+      case 3:
+        if(SmartError.checkVolts(FilteredSamples.FastipVolts.getValue(), FilteredSamples.FastGlowAmps.getValue())) {
+          showBatteryIcon(getBatteryVoltage(true));
+        }
+        else {
+          _display.fillRect(xPos, yPos, BatteryIconInfo.width, BatteryIconInfo.height, BLACK);
+        }
+        break;
+      case 0:
+        showBatteryIcon(getBatteryVoltage(true));
+        break;
+    }
   }
 
   showWifiIcon();
@@ -285,6 +309,7 @@ CScreenHeader::showTime()
     int xPos = X_WIFI_ICON + WifiIconInfo.width + WifiInIconInfo.width;  // rhs of wifi conglomeration
     if(isWifiAP())  xPos += 4;                             // add more if an Access Point
     
+    _display.fillRect(xPos - 15, Y_CLOCK, 30, arial_8ptFontInfo.nBitsPerLine, BLACK);
     _printMenuText(X_CLOCK, Y_CLOCK, msg);
   }
 }
diff --git a/src/Afterburner/src/OLED/ScreenHeader.h b/src/Afterburner/src/OLED/ScreenHeader.h
index e263d8c..d9aeed1 100644
--- a/src/Afterburner/src/OLED/ScreenHeader.h
+++ b/src/Afterburner/src/OLED/ScreenHeader.h
@@ -44,7 +44,8 @@ class CScreenHeader : public CScreen {
   sScreenholdoff _UpAnnotation;
   sScreenholdoff _DnAnnotation;
   bool _colon;
-  int  _animateCount;
+  uint8_t  _animateCount;
+  uint8_t  _batteryCount;
 protected:
   void showBTicon();
   void showWifiIcon();
@@ -53,7 +54,7 @@ protected:
   virtual void showTime();  // x location depends upon how many timers are active
 public:
   CScreenHeader(C128x64_OLED& disp, CScreenManager& mgr); 
-  bool show();
+  bool show(bool erase);
   bool animate();
 };
 
diff --git a/src/Afterburner/src/OLED/ScreenManager.cpp b/src/Afterburner/src/OLED/ScreenManager.cpp
index ad3eb55..15d2dc7 100644
--- a/src/Afterburner/src/OLED/ScreenManager.cpp
+++ b/src/Afterburner/src/OLED/ScreenManager.cpp
@@ -30,6 +30,7 @@
 #include "ClockScreen.h"
 #include "RebootScreen.h"
 #include "HeaterSettingsScreen.h"
+#include "FuelCalScreen.h"
 #include "SettingsScreen.h"
 #include "ThermostatModeScreen.h"
 #include "FontDumpScreen.h"
diff --git a/src/Afterburner/src/OLED/SetClockScreen.cpp b/src/Afterburner/src/OLED/SetClockScreen.cpp
index 7e6280e..9275d2b 100644
--- a/src/Afterburner/src/OLED/SetClockScreen.cpp
+++ b/src/Afterburner/src/OLED/SetClockScreen.cpp
@@ -43,6 +43,7 @@ CSetClockScreen::CSetClockScreen(C128x64_OLED& display, CScreenManager& mgr) : C
 void
 CSetClockScreen::onSelect()
 {
+  CScreenHeader::onSelect();
   _initUI();
 }
 
@@ -67,7 +68,7 @@ CSetClockScreen::show()
   if(deltaT >= 0) {
     _nextT += 1000;
 
-    CScreenHeader::show();
+    CScreenHeader::show(false);
 
     char str[16];
     int xPos, yPos;
diff --git a/src/Afterburner/src/OLED/SetTimerScreen.cpp b/src/Afterburner/src/OLED/SetTimerScreen.cpp
index 482f36b..3dcf636 100644
--- a/src/Afterburner/src/OLED/SetTimerScreen.cpp
+++ b/src/Afterburner/src/OLED/SetTimerScreen.cpp
@@ -47,6 +47,7 @@ CSetTimerScreen::CSetTimerScreen(C128x64_OLED& display, CScreenManager& mgr, int
 void 
 CSetTimerScreen::onSelect()
 {
+  CScreenHeader::onSelect();
   _initUI();
   NVstore.getTimerInfo(_timerID, _timerInfo);
 }
@@ -62,7 +63,7 @@ CSetTimerScreen::_initUI()
 bool 
 CSetTimerScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
 
   char str[20];
   int xPos, yPos;
diff --git a/src/Afterburner/src/OLED/SettingsScreen.cpp b/src/Afterburner/src/OLED/SettingsScreen.cpp
index 4de30b8..fc65b93 100644
--- a/src/Afterburner/src/OLED/SettingsScreen.cpp
+++ b/src/Afterburner/src/OLED/SettingsScreen.cpp
@@ -66,7 +66,7 @@ CSettingsScreen::show()
 {
   char str[16];
   
-  CScreenHeader::show();
+  CScreenHeader::show(false);
 
   _display.writeFillRect(0, 16, 84, 12, WHITE);
   _printInverted(3, 18, "Heater Tuning", true);
diff --git a/src/Afterburner/src/OLED/WiFiScreen.cpp b/src/Afterburner/src/OLED/WiFiScreen.cpp
index 083f4e4..c47fc3e 100644
--- a/src/Afterburner/src/OLED/WiFiScreen.cpp
+++ b/src/Afterburner/src/OLED/WiFiScreen.cpp
@@ -48,6 +48,7 @@ CWiFiScreen::CWiFiScreen(C128x64_OLED& display, CScreenManager& mgr) : CScreenHe
 void
 CWiFiScreen::onSelect()
 {
+  CScreenHeader::onSelect();
   _initUI();
 }
 
@@ -87,7 +88,7 @@ CWiFiScreen::_initUI()
 bool 
 CWiFiScreen::show()
 {
-  CScreenHeader::show();
+  CScreenHeader::show(false);
   
   int yPos = 18;
     
diff --git a/src/Afterburner/src/OLED/fonts/Arial.c b/src/Afterburner/src/OLED/fonts/Arial.c
index d06e8fa..48f80f5 100644
--- a/src/Afterburner/src/OLED/fonts/Arial.c
+++ b/src/Afterburner/src/OLED/fonts/Arial.c
@@ -662,11 +662,19 @@ const uint8_t PROGMEM arial_8ptBitmaps [] =
 	0x01, 0x00, //        #      
 
 	// @870 '~' (5 pixels wide)
-	0x03, 0x00, //       ##      
+	0x01, 0x00, //        #      
 	0x02, 0x00, //       #       
 	0x03, 0x00, //       ##      
 	0x01, 0x00, //        #      
 	0x02, 0x00, //       #       
+
+	// @880 '1' (5 pixels wide)
+  0x00, 0x00, //
+	0x04, 0x00, //      #        
+	0x08, 0x00, //     #         
+	0x1F, 0xE0, //    ########   
+  0x00, 0x00, //
+
 };
 
 // Character descriptors for Arial 8pt
@@ -690,7 +698,7 @@ const FONT_CHAR_INFO PROGMEM arial_8ptDescriptors[] =
 	{1, 14, 100}, 		// '.' 
 	{3, 14, 102}, 		// '/' 
 	{5, 14, 108}, 		// '0' 
-	{3, 14, 118}, 		// '1' 
+	{5, 14, 880}, 		// '1' 
 	{5, 14, 124}, 		// '2' 
 	{5, 14, 134}, 		// '3' 
 	{5, 14, 144}, 		// '4' 
diff --git a/src/Afterburner/src/OLED/fonts/Icons.cpp b/src/Afterburner/src/OLED/fonts/Icons.cpp
index 5d48e70..6ebf1aa 100644
--- a/src/Afterburner/src/OLED/fonts/Icons.cpp
+++ b/src/Afterburner/src/OLED/fonts/Icons.cpp
@@ -375,6 +375,25 @@ const uint8_t FuelIcon [] PROGMEM = {
 };
 const BITMAP_INFO FuelIconInfo(7, 12, FuelIcon);
 
+// 
+//  Image data for FuelIconSmall
+// 
+
+const uint8_t PROGMEM FuelIconSmall[]  =
+{
+	0x20, //   #  
+	0x20, //   #  
+	0x70, //  ### 
+	0x70, //  ### 
+	0xF8, // #####
+	0xF8, // #####
+	0xF8, // #####
+	0xF8, // #####
+	0x70, //  ### 
+};
+const BITMAP_INFO FuelIconSmallInfo(5, 9, FuelIconSmall);
+
+
 // 'Target', 13x13px
 const uint8_t TargetIcon [] PROGMEM = {
   0x0f, 0x80, //     #####
@@ -1083,3 +1102,25 @@ const uint8_t PROGMEM resetIcon[]  =
 };
 const BITMAP_INFO resetIconInfo(17, 10, resetIcon);
 
+// 
+//  Image data for miniThermo
+// 
+
+const uint8_t PROGMEM miniThermoIcon[]  =
+{
+	0x30, //   ##  
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x48, //  #  # 
+	0x78, //  #### 
+	0xFC, // ######
+	0xFC, // ######
+	0xFC, // ######
+	0x78, //  #### 
+};
+const BITMAP_INFO miniThermoIconInfo(6, 13, miniThermoIcon);
+
diff --git a/src/Afterburner/src/OLED/fonts/Icons.h b/src/Afterburner/src/OLED/fonts/Icons.h
index fa202bb..a7a1c6c 100644
--- a/src/Afterburner/src/OLED/fonts/Icons.h
+++ b/src/Afterburner/src/OLED/fonts/Icons.h
@@ -65,8 +65,8 @@ extern const BITMAP_INFO FanIcon4Info;
 
 // 'FuelIcon', 7x12px
 extern const BITMAP_INFO FuelIconInfo;
+extern const BITMAP_INFO FuelIconSmallInfo;
 
-// 'Target', 13x13px
 extern const BITMAP_INFO TargetIconInfo;
 
 extern const BITMAP_INFO RepeatIconInfo;
@@ -77,7 +77,8 @@ extern const BITMAP_INFO LargeTimerIconInfo;
 extern const BITMAP_INFO VerticalRepeatIconInfo;
 
 extern const BITMAP_INFO CrossLgIconInfo;
-extern const BITMAP_INFO CrossIconInfo;
+extern const BITMAP_INFO CrossIconInfo
+;
 
 // Bitmap for open
 extern const BITMAP_INFO OpenIconInfo;
@@ -137,3 +138,4 @@ extern const BITMAP_INFO ThermostatDegCIconInfo;
 extern const BITMAP_INFO ThermostatDegFIconInfo;
 extern const BITMAP_INFO ThermostatHzIconInfo;
 extern const BITMAP_INFO resetIconInfo;
+extern const BITMAP_INFO miniThermoIconInfo;
diff --git a/src/Afterburner/src/Protocol/Protocol.cpp b/src/Afterburner/src/Protocol/Protocol.cpp
index b97bb2f..5426403 100644
--- a/src/Afterburner/src/Protocol/Protocol.cpp
+++ b/src/Afterburner/src/Protocol/Protocol.cpp
@@ -368,7 +368,7 @@ const char* Errstates [] PROGMEM = {
   "Flame out",       // [9] E-08
   "Temp sense",      // [10] E-09
   "Ignition fail",   // [11] E-10          SmartError manufactured state - sensing runstate 2 -> >5
-  "Failed 1st ignition attempt",  // [12] E-11  SmartError manufactured state - sensing runstate 2 -> 3
+  "Failed 1st ignite",  // [12] E-11  SmartError manufactured state - sensing runstate 2 -> 3
   "Unknown error?"   // mystery code!
 };
 
@@ -385,7 +385,7 @@ const char* ErrstatesEx [] PROGMEM = {
   "E-08: Flame out",       // [9] E-08
   "E-09: Temp sense",      // [10] E-09
   "E-10: Ignition fail",   // [11] E-10  SmartError manufactured state - sensing runstate 2 -> >5
-  "E-11: Failed 1st ignition attempt",  // [12] E-11  SmartError manufactured state - sensing runstate 2 -> 3
+  "E-11: Failed 1st ignite",  // [12] E-11  SmartError manufactured state - sensing runstate 2 -> 3
   "Unknown error?"   // mystery code!
 };
 
diff --git a/src/Afterburner/src/Protocol/SmartError.cpp b/src/Afterburner/src/Protocol/SmartError.cpp
index 57e6174..723cd20 100644
--- a/src/Afterburner/src/Protocol/SmartError.cpp
+++ b/src/Afterburner/src/Protocol/SmartError.cpp
@@ -2,7 +2,7 @@
  * This file is part of the "bluetoothheater" distribution 
  * (https://gitlab.com/mrjones.id.au/bluetoothheater) 
  *
- * Copyright (C) 2018  Ray Jones <ray@mrjones.id.au>
+ * Copyright (C) 2019  Ray Jones <ray@mrjones.id.au>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -21,6 +21,10 @@
 
 #include "SmartError.h"
 #include "TxManage.h"
+#include "../Utility/helpers.h"
+#include "../Utility/macros.h"
+#include "../Utility/NVStorage.h"
+#include "../Utility/DataFilter.h"
 
 CSmartError::CSmartError()
 {
@@ -83,12 +87,12 @@ CSmartError::monitor(uint8_t newRunState)
       else if(newRunState > 5) {
         // transitioned from preheat to post glow
         // - second ignition attempt failed, heater is shutting down
-        m_Error = 11;
+        m_Error = 11;   // +1 over displayed error code
       }
       else if(newRunState == 3) {
         // transitioned from preheat to retry 
         // - first ignition attempt failed, heater will retry
-        m_Error = 12;
+        m_Error = 12;   // +1 over displayed error code
       }
     }
   }
@@ -106,7 +110,24 @@ CSmartError::monitor(uint8_t newRunState)
     }
   }
 
-  m_prevRunState = newRunState;
+   m_prevRunState = newRunState;
+}
+
+bool
+CSmartError::checkVolts(float ipVolts, float glowI)
+{
+ // check for low voltage
+ // values here are x10 integers
+ if(NVstore.getHeaterTuning().lowVolts) {   // only if enabled
+    float cableComp = glowI * 0.1;             // allow 1V drop for 10A current (bit naive but better than no compensation)
+    float Thresh = NVstore.getHeaterTuning().getLVC() - cableComp;  // NVstore
+    if(ipVolts < Thresh) {
+      m_Error = 2;     // +1 over displayed error code
+      requestOff();
+      return false;
+    }
+  }
+  return true;
 }
 
 // return our smart error, if it exists, as the registered code
diff --git a/src/Afterburner/src/Protocol/SmartError.h b/src/Afterburner/src/Protocol/SmartError.h
index 90ad624..0c91d09 100644
--- a/src/Afterburner/src/Protocol/SmartError.h
+++ b/src/Afterburner/src/Protocol/SmartError.h
@@ -31,6 +31,7 @@ public:
   void inhibit();
   void monitor(const CProtocol& heaterFrame);
   void monitor(uint8_t runstate);
+  bool checkVolts(float volts, float plugI);
   uint8_t getError();
 };
 
diff --git a/src/Afterburner/src/Utility/BTC_JSON.cpp b/src/Afterburner/src/Utility/BTC_JSON.cpp
index a3e4a90..94d7625 100644
--- a/src/Afterburner/src/Utility/BTC_JSON.cpp
+++ b/src/Afterburner/src/Utility/BTC_JSON.cpp
@@ -277,7 +277,29 @@ void interpretJsonCommand(char* pLine)
         sHeaterTuning ht = NVstore.getHeaterTuning();
         ht.pumpCal = fCal;
         NVstore.setHeaterTuning(ht);
-        NVstore.save();
+      }
+    }
+    else if(strcmp("TempOffset", it->key) == 0) {
+      float fCal = it->value.as<float>();
+      if(INBOUNDS(fCal, -10.0, +10.0)) {
+        sHeaterTuning ht = NVstore.getHeaterTuning();
+        ht.tempOfs = fCal;
+        NVstore.setHeaterTuning(ht);
+      }
+    }
+    else if(strcmp("LowVoltCutout", it->key) == 0) {
+      float fCal = it->value.as<float>();
+      if(fCal != 0) {
+        bool bOK = false;
+        if(NVstore.getHeaterTuning().sysVoltage == 120)
+          bOK = INBOUNDS(fCal, 10.0, 12.5);
+        else
+          bOK = INBOUNDS(fCal, 20.0, 25.0);
+        if(bOK) {
+          sHeaterTuning ht = NVstore.getHeaterTuning();
+          ht.lowVolts = fCal;
+          NVstore.setHeaterTuning(ht);
+        }
       }
     }
   }
@@ -325,7 +347,7 @@ bool makeJSONString(CModerator& moderator, char* opStr, int len)
 	bSend |= moderator.addJson("FanRPM", getFanSpeed(), root );
 	bSend |= moderator.addJson("FanVoltage", getHeaterInfo().getFan_Voltage(), root );
 	bSend |= moderator.addJson("FanSensor", getHeaterInfo().getFan_Sensor(), root );
-	bSend |= moderator.addJson("InputVoltage", getBatteryVoltage(), root );
+	bSend |= moderator.addJson("InputVoltage", getBatteryVoltage(false), root );
 	bSend |= moderator.addJson("SystemVoltage", getHeaterInfo().getSystemVoltage(), root );
 	bSend |= moderator.addJson("GlowVoltage", getGlowVolts(), root );
 	bSend |= moderator.addJson("GlowCurrent", getGlowCurrent(), root );
@@ -354,9 +376,11 @@ bool makeJSONStringEx(CModerator& moderator, char* opStr, int len)
   bSend |= moderator.addJson("ThermostatUndertemp", NVstore.getUserSettings().cyclic.Start, root); 
   bSend |= moderator.addJson("CyclicTemp", getDemandDegC(), root);             // actual pivot point for cyclic mode
   bSend |= moderator.addJson("CyclicOff", stop, root);                         // threshold of over temp for cyclic mode
-  bSend |= moderator.addJson("CyclicOn", NVstore.getUserSettings().cyclic.Start, root); // threshold of under temp for cyclic mode
-  bSend |= moderator.addJson("PumpCount", RTC_Store.getFuelGauge(), root);     // running count of pump strokes
-  bSend |= moderator.addJson("PumpCal", NVstore.getHeaterTuning().pumpCal, root);     // ml/stroke
+  bSend |= moderator.addJson("CyclicOn", NVstore.getUserSettings().cyclic.Start, root);  // threshold of under temp for cyclic mode
+  bSend |= moderator.addJson("PumpCount", RTC_Store.getFuelGauge(), root);               // running count of pump strokes
+  bSend |= moderator.addJson("PumpCal", NVstore.getHeaterTuning().pumpCal, root);        // mL/stroke
+  bSend |= moderator.addJson("TempOffset", NVstore.getHeaterTuning().tempOfs, root);     // degC offset
+  bSend |= moderator.addJson("LowVoltCutout", NVstore.getHeaterTuning().lowVolts, root); // low volatge cutout
 
   if(bSend) {
 		root.printTo(opStr, len);
diff --git a/src/Afterburner/src/Utility/DataFilter.h b/src/Afterburner/src/Utility/DataFilter.h
index 218e4c0..b25e31a 100644
--- a/src/Afterburner/src/Utility/DataFilter.h
+++ b/src/Afterburner/src/Utility/DataFilter.h
@@ -2,7 +2,7 @@
  * This file is part of the "bluetoothheater" distribution 
  * (https://gitlab.com/mrjones.id.au/bluetoothheater) 
  *
- * Copyright (C) 2018  Ray Jones <ray@mrjones.id.au>
+ * Copyright (C) 2019  Ray Jones <ray@mrjones.id.au>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -44,6 +44,11 @@ struct sFilteredData {
   CExpMean GlowAmps;
   CExpMean Fan;
   CExpMean AmbientTemp;
+  CExpMean FastipVolts;
+  CExpMean FastGlowAmps;
 };
 
+extern sFilteredData FilteredSamples;
+
+
 #endif
diff --git a/src/Afterburner/src/Utility/FuelGauge.cpp b/src/Afterburner/src/Utility/FuelGauge.cpp
index 61c665e..2d985ba 100644
--- a/src/Afterburner/src/Utility/FuelGauge.cpp
+++ b/src/Afterburner/src/Utility/FuelGauge.cpp
@@ -71,7 +71,7 @@ CFuelGauge::Integrate(float Hz)
 }
 
 float 
-CFuelGauge::Used_ml()
+CFuelGauge::Used_mL()
 {
   return _pumpStrokes * _pumpCal;   // strokes * millilitre / stroke
 }
diff --git a/src/Afterburner/src/Utility/FuelGauge.h b/src/Afterburner/src/Utility/FuelGauge.h
index 20ca094..88c0af9 100644
--- a/src/Afterburner/src/Utility/FuelGauge.h
+++ b/src/Afterburner/src/Utility/FuelGauge.h
@@ -34,7 +34,7 @@ public:
   void init(float fuelUsed = 0);
   void reset();
   void Integrate(float Hz);
-  float Used_ml();
+  float Used_mL();
   float Used_strokes();
 };
 
diff --git a/src/Afterburner/src/Utility/NVStorage.cpp b/src/Afterburner/src/Utility/NVStorage.cpp
index bc508c6..c3f6925 100644
--- a/src/Afterburner/src/Utility/NVStorage.cpp
+++ b/src/Afterburner/src/Utility/NVStorage.cpp
@@ -97,6 +97,11 @@ sHeaterTuning::setSysVoltage(float fVal)
   }
 }
 
+float  
+sHeaterTuning::getLVC() const
+{
+  return lowVolts * 0.1;
+}
 
 void 
 CHeaterStorage::getTimerInfo(int idx, sTimer& timerInfo)
@@ -235,7 +240,12 @@ sHeaterTuning::load()
   validatedLoad("systemVoltage", sysVoltage, 120, u8Match2, 120, 240);
   validatedLoad("fanSensor", fanSensor, 1, u8inBounds, 1, 2);
   validatedLoad("glowDrive", glowDrive, 5, u8inBounds, 1, 6);
+  if(sysVoltage == 120)
+    validatedLoad("lowVolts", lowVolts, 115, u8inBounds, 100, 125);
+  else
+    validatedLoad("lowVolts", lowVolts, 230, u8inBounds, 200, 250);
   validatedLoad("pumpCal", pumpCal, 0.02, 0.001, 1);
+  validatedLoad("tempOfs", tempOfs, 0.0, -10.0, +10.0);
   preferences.end();    
 }
 
@@ -252,7 +262,9 @@ sHeaterTuning::save()
   preferences.putUChar("systemVoltage", sysVoltage);
   preferences.putUChar("fanSensor", fanSensor);
   preferences.putUChar("glowDrive", glowDrive);
+  preferences.putUChar("lowVolts", lowVolts);
   preferences.putFloat("pumpCal", pumpCal);
+  preferences.putFloat("tempOfs", tempOfs);
   preferences.end();    
 }
 
diff --git a/src/Afterburner/src/Utility/NVStorage.h b/src/Afterburner/src/Utility/NVStorage.h
index 37bd258..b58633f 100644
--- a/src/Afterburner/src/Utility/NVStorage.h
+++ b/src/Afterburner/src/Utility/NVStorage.h
@@ -37,10 +37,12 @@ struct sHeaterTuning : public CESP32_NVStorage {
   uint8_t   Pmax;
   uint16_t  Fmin;
   uint16_t  Fmax;
-  uint8_t   sysVoltage;
+  uint8_t   sysVoltage;  // x10 
   uint8_t   fanSensor;
   uint8_t   glowDrive;
+  uint8_t   lowVolts;    // x10
   float     pumpCal;
+  float     tempOfs;
 
   bool valid() {
     bool retval = true;
@@ -52,6 +54,11 @@ struct sHeaterTuning : public CESP32_NVStorage {
     retval &= fanSensor == 1 || fanSensor == 2;
     retval &= INBOUNDS(glowDrive, 1, 6);
     retval &= INBOUNDS(pumpCal, 0.001, 1.0);
+    if(sysVoltage == 120)
+      retval &= INBOUNDS(lowVolts, 100, 125);
+    else 
+      retval &= INBOUNDS(lowVolts, 200, 250);
+    retval &= INBOUNDS(tempOfs, -10, +10);
     return retval;
   };
   void init() {
@@ -63,6 +70,8 @@ struct sHeaterTuning : public CESP32_NVStorage {
     fanSensor = 1;
     glowDrive = 5;
     pumpCal = 0.02;
+    lowVolts = 115;
+    tempOfs = 0;
   };
   void load();
   void save();
@@ -75,6 +84,8 @@ struct sHeaterTuning : public CESP32_NVStorage {
     fanSensor = rhs.fanSensor;
     glowDrive = rhs.glowDrive;
     pumpCal = rhs.pumpCal;
+    lowVolts = rhs.lowVolts;
+    tempOfs = rhs.tempOfs;
     return *this;
   }
   float getPmin() const;
@@ -82,6 +93,7 @@ struct sHeaterTuning : public CESP32_NVStorage {
   void setPmin(float val);
   void setPmax(float val);
   void setSysVoltage(float val);
+  float getLVC() const;
 };
 
 struct sHomeMenuActions {
diff --git a/src/Afterburner/src/Utility/helpers.h b/src/Afterburner/src/Utility/helpers.h
index 95f07a7..11265f7 100644
--- a/src/Afterburner/src/Utility/helpers.h
+++ b/src/Afterburner/src/Utility/helpers.h
@@ -78,19 +78,12 @@ extern void  setUploadSize(long val);
 extern void getGPIOinfo(sGPIO& info);
 extern void simulateGPIOin(uint8_t newKey);   
 extern void setDegFMode(bool state);
-extern float getBatteryVoltage();
+extern float getBatteryVoltage(bool fast);
 extern float getGlowVolts();
 extern float getGlowCurrent();
 extern float getFanSpeed();
 extern int sysUptime();
 
-/* extern void setFuelGauge_RTC(float val);
-extern void getFuelGauge_RTC(float& val);
-extern void setDesiredTemp_RTC(uint8_t val);
-extern void getDesiredTemp_RTC(uint8_t& val);
-extern void setDesiredPump_RTC(uint8_t val);
-extern void getDesiredPump_RTC(uint8_t& val);*/
-
 
 extern void ShowOTAScreen(int percent=0, eOTAmodes updateType=eOTAnormal);
 
diff --git a/src/Afterburner/src/Utility/macros.h b/src/Afterburner/src/Utility/macros.h
index 8f1701a..04d9ee8 100644
--- a/src/Afterburner/src/Utility/macros.h
+++ b/src/Afterburner/src/Utility/macros.h
@@ -2,7 +2,7 @@
  * This file is part of the "bluetoothheater" distribution 
  * (https://gitlab.com/mrjones.id.au/bluetoothheater) 
  *
- * Copyright (C) 2018  Ray Jones <ray@mrjones.id.au>
+ * Copyright (C) 2019  Ray Jones <ray@mrjones.id.au>
  * Copyright (C) 2018  James Clark
  *
  * This program is free software: you can redistribute it and/or modify
@@ -23,12 +23,12 @@
 #ifndef __MACROS_H__
 #define __MACROS_H__
 
-#define LOWERLIMIT(A, B) if((A) < (B)) (A) = (B)
-#define UPPERLIMIT(A, B) if((A) > (B)) (A) = (B)
-#define WRAPUPPERLIMIT(A, B, C) if((A) > (B)) (A) = (C)        
-#define WRAPLOWERLIMIT(A, B, C) if((A) < (B)) (A) = (C)        
-#define WRAPLIMITS(A, B, C) if((A) < (B)) (A) = (C) ; if((A) > (C)) (A) = (B)               
+#define LOWERLIMIT(A, B) { if((A) < (B)) (A) = (B); }
+#define UPPERLIMIT(A, B) { if((A) > (B)) (A) = (B); }
+#define WRAPUPPERLIMIT(A, B, C) { if((A) > (B)) (A) = (C); }
+#define WRAPLOWERLIMIT(A, B, C) { if((A) < (B)) (A) = (C); }    
+#define WRAPLIMITS(A, B, C) { if((A) < (B)) (A) = (C) ; if((A) > (C)) (A) = (B); }              
 #define INBOUNDS(TST, MIN, MAX) (((TST) >= (MIN)) && ((TST) <= (MAX)))
-#define BOUNDSLIMIT(A, B, C) if((A) < (B)) (A) = (B); if((A) > (C)) (A) = (C)
+#define BOUNDSLIMIT(A, B, C) { if((A) < (B)) (A) = (B); if((A) > (C)) (A) = (C); }
 
 #endif
\ No newline at end of file