Index: dialin/dg/concentrate_pumps.py
===================================================================
diff -u -rd531ce09d0240e0ae542ea33cf8ebe4b8169825b -rab4ad43e62b63fb9594ec7100dddc3a08785539c
--- dialin/dg/concentrate_pumps.py	(.../concentrate_pumps.py)	(revision d531ce09d0240e0ae542ea33cf8ebe4b8169825b)
+++ dialin/dg/concentrate_pumps.py	(.../concentrate_pumps.py)	(revision ab4ad43e62b63fb9594ec7100dddc3a08785539c)
@@ -20,8 +20,16 @@
 from ..utils.base import _AbstractSubSystem, _publish
 from ..common.msg_defs import MsgIds
 from logging import Logger
+import enum
 
+class ConcentratePumpsEnum(enum.Enum):
+    CP1 = 0
+    CP2 = 1
 
+    @classmethod
+    def has_value(cls, value):
+        return value in cls._value2member_map_
+
 class ConcentratePumps(_AbstractSubSystem):
     """
     ConcentratePumps
@@ -89,32 +97,28 @@
         self.concentrate_pump_cp2_target = cp2_target[0]
         self.concentrate_pump_cp2 = cp2[0]
 
-    def cmd_concentrate_pump_on_request(self):
-        payload = integer_to_bytearray(1)
-        message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
-                                              message_id=MsgIds.MSG_ID_CONCENTRATE_PUMP_STATE_CHANGE_REQUEST.value,
-                                              payload=payload)
-        # Send message
-        received_message = self.can_interface.send(message)
-        self.logger.debug("Requested to turn concentrate pumps on!")
+    def cmd_concentrate_pump_state_change_request(self, pump_id, on=False):
+        """
+        Constructs and sends the concentrate pump state change request command
 
-        # If there is content...
-        if received_message is not None:
-            # response payload is OK or not OK
-            return received_message['message'][DenaliMessage.PAYLOAD_START_INDEX]
-        else:
-            self.logger.error("Timeout!!!!")
-            return False
+        @param pump_id: unsigned int - concentrate pump ID
+        @param on:  bool - 1 to turn on, 0 to turn off
+        @return: 1 if successful, zero otherwise
 
-
-    def cmd_concentrate_pump_off_request(self):
-        payload = integer_to_bytearray(0)
+        Concentrate pump IDs: \n
+            0 = CP1 \n
+            1 = CP2 \n
+        """
+        payload = integer_to_bytearray(0) + integer_to_bytearray(on) + integer_to_bytearray(pump_id)
         message = DenaliMessage.build_message(channel_id=DenaliChannels.dialin_to_dg_ch_id,
                                               message_id=MsgIds.MSG_ID_CONCENTRATE_PUMP_STATE_CHANGE_REQUEST.value,
                                               payload=payload)
         # Send message
         received_message = self.can_interface.send(message)
-        self.logger.debug("Requested to turn concentrate pumps off")
+        if on:
+            self.logger.debug("Requested to turn on concentrate pump: CP" + str(pump_id))
+        else:
+            self.logger.debug("Requested to turn off concentrate pump: CP" + str(pump_id))
 
         # If there is content...
         if received_message is not None: