diff --git a/R51MHeatpumpIR.cpp b/R51MHeatpumpIR.cpp
new file mode 100644
index 0000000..0be76bd
--- /dev/null
+++ b/R51MHeatpumpIR.cpp
@@ -0,0 +1,96 @@
+#include <R51MHeatpumpIR.h>
+
+R51MHeatpumpIR::R51MHeatpumpIR() : HeatpumpIR()
+{
+  static const char model[] PROGMEM = "R51M";
+  static const char info[]  PROGMEM = "{}";
+  
+  _model = model;
+  _info = info;
+}
+
+
+void R51MHeatpumpIR::send(IRSender& IR, uint8_t powerModeCmd, uint8_t operatingModeCmd, uint8_t fanSpeedCmd, uint8_t temperatureCmd, uint8_t swingVCmd, uint8_t swingHCmd)
+{
+  const static byte tempMap [] PROGMEM = {0,1,3,2,6,7,5,4,12,13,9,8,10,11 };
+  // Sensible defaults for the heat pump mode
+  
+  uint8_t data[] = { 0xB2, 0x0F, 0x00  }; // The actual data is in this part
+  
+  // Send the R51M code
+  if (powerModeCmd == POWER_OFF)
+  {
+    data[1] = R51M_AIRCON1_MODE_OFF;
+    data[2] = R51M_AIRCON1_MODE_OFF_TEMP;
+  }
+  else
+  {
+    switch (operatingModeCmd)
+    {
+      case MODE_AUTO:
+        data[1] |= R51M_AIRCON1_FAN_DRY;
+        data[2] |= R51M_AIRCON1_MODE_AUTO;
+        break;
+      case MODE_COOL:
+        data[2] |= R51M_AIRCON1_MODE_COOL;
+        break;
+      case MODE_DRY:
+        data[1] |= R51M_AIRCON1_FAN_DRY;
+        data[2] |= R51M_AIRCON1_MODE_FANDRY;
+        break;
+      case MODE_FAN:
+        data[2] |= R51M_AIRCON1_MODE_FANDRY;
+        break;    
+    }
+    if (operatingModeCmd == MODE_COOL || operatingModeCmd == MODE_FAN)
+    {
+      switch (fanSpeedCmd)
+      {
+        case FAN_AUTO:
+          data[1] |= R51M_AIRCON1_FAN_AUTO;
+          break;
+        case FAN_1:
+          data[1] |= R51M_AIRCON1_FAN1;
+          break;
+        case FAN_2:
+          data[1] |= R51M_AIRCON1_FAN2;
+          break;
+        case FAN_3:
+          data[1] |= R51M_AIRCON1_FAN3;
+          break;
+      }
+    }
+    if (operatingModeCmd == MODE_COOL || operatingModeCmd == MODE_AUTO || operatingModeCmd == MODE_DRY)
+    {
+      if (temperatureCmd < 17 || temperatureCmd > 30) temperatureCmd = 24;
+      data[2] |= (pgm_read_byte_near(tempMap + (temperatureCmd - 17)) << 4);
+    }
+    else data[2] |= R51M_AIRCON1_MODE_OFF_TEMP;
+  }
+   
+  // 38 kHz PWM frequency
+  IR.setFrequency(38);
+  IR.space(R51M_AIRCON1_ZERO_SPACE);
+  // Header
+  IR.mark(R51M_AIRCON1_HDR_MARK-500); IR.space(R51M_AIRCON1_HDR_SPACE);
+
+  // Payload data message part
+  for (int i=0; i<3; i++) {
+    IR.sendIRbyte(IR.bitReverse(data[i]), R51M_AIRCON1_BIT_MARK, R51M_AIRCON1_ZERO_SPACE, R51M_AIRCON1_ONE_SPACE);
+    IR.sendIRbyte(IR.bitReverse(~data[i]), R51M_AIRCON1_BIT_MARK, R51M_AIRCON1_ZERO_SPACE, R51M_AIRCON1_ONE_SPACE);
+  }
+ 
+  IR.mark(R51M_AIRCON1_BIT_MARK); IR.space(5000);
+  // Header
+  IR.mark(R51M_AIRCON1_HDR_MARK); IR.space(R51M_AIRCON1_HDR_SPACE);
+  
+  for (int i=0; i<3; i++) {
+    IR.sendIRbyte(IR.bitReverse(data[i]), R51M_AIRCON1_BIT_MARK, R51M_AIRCON1_ZERO_SPACE, R51M_AIRCON1_ONE_SPACE);
+    IR.sendIRbyte(IR.bitReverse(~data[i]), R51M_AIRCON1_BIT_MARK, R51M_AIRCON1_ZERO_SPACE, R51M_AIRCON1_ONE_SPACE);
+  }
+ 
+  // End mark
+  IR.mark(R51M_AIRCON1_BIT_MARK);
+  IR.space(0);
+}
+
diff --git a/R51MHeatpumpIR.h b/R51MHeatpumpIR.h
new file mode 100644
index 0000000..526b9b2
--- /dev/null
+++ b/R51MHeatpumpIR.h
@@ -0,0 +1,34 @@
+/*
+    Marshall / Conqueror heatpump control (remote control P/N R51M/CE)
+*/
+#ifndef R51MHeatpumpIR_h
+#define R51MHeatpumpIR_h
+
+#include <HeatpumpIR.h>
+
+// R51M timing constants
+#define R51M_AIRCON1_HDR_MARK   4400
+#define R51M_AIRCON1_HDR_SPACE  4150
+#define R51M_AIRCON1_BIT_MARK   550
+#define R51M_AIRCON1_ONE_SPACE  1520
+#define R51M_AIRCON1_ZERO_SPACE 550
+
+#define R51M_AIRCON1_MODE_AUTO  0x08 // Operating mode
+#define R51M_AIRCON1_MODE_COOL  0x00
+#define R51M_AIRCON1_MODE_FANDRY   0x04
+#define R51M_AIRCON1_MODE_OFF   0x7B // Power OFF
+#define R51M_AIRCON1_MODE_OFF_TEMP 0xE0
+#define R51M_AIRCON1_FAN_AUTO  0xB0 // Fan speed
+#define R51M_AIRCON1_FAN_DRY   0x10 // Fan speed
+#define R51M_AIRCON1_FAN1       0x90 // * low
+#define R51M_AIRCON1_FAN2       0x50 // * med
+#define R51M_AIRCON1_FAN3       0x30 // * high
+
+class R51MHeatpumpIR : public HeatpumpIR
+{
+  public:
+    R51MHeatpumpIR();
+    void send(IRSender& IR, uint8_t powerModeCmd, uint8_t operatingModeCmd, uint8_t fanSpeedCmd, uint8_t temperatureCmd, uint8_t swingVCmd, uint8_t swingHCmd);
+};
+
+#endif
\ No newline at end of file