GB - 6
HDB - Carrier Room Controller 2
Room Controller 2 configuration,  troubleshooting
Item # Value Descrizione
Cold draft thermistor
20
1
0
Cold Draft thermistor installed
Cold Draft thermistor not installed
CCN address
21
1 – 199 CCN address
Electric Heaters Option
22
0
1
2
3 – 199
Not installed
Low power without “booster heating”
Low power with “booster heating”
High power
Dead band
23
1
2 – 6
6
The unit uses only the values from 2 to 6
From 2 to 6
>  6 is equal to 6
Off / ECO
24
0
1
Turning  the unit OFF, only the antifreeze protection is active
Turning the unit OFF, ECO mode is active.
The units are configured at the factory. In the case of check or 
change, the installer should follow the instructions below:
.  Check all the electric connections (instructions and wiring    
diagrams).
.  Turning the CRC control off, keep the UP and DOWN buttons     
simultaneously pressed for more than 5 seconds.
.  After 5 seconds, the code “20” is displayed.
.PresstheMODEbuttontocheckorchangetheset-upvalue
using UP and DOWN buttons.
.  Press FAN button to send the unit the new configuration; 
   reception of the new vales will be confirmed by the unit.
.PressMODEtoscrollalltheitemsavailableasshowninthetable
below.
Note: 
When 30 seconds have elapsed and no buttons have been 
pressed, the control  will automatically exit the configuration 
mode and the procedure has to be restarted.
  Symptom Possible Cause Things to check Solution
No LCD  display
 1) mis-wiring of the 12 volt 
  power to Room Controller 2  control.    
1)  Verify that +12V and Ground are con-
nected to the proper terrminals of the 
Controller.  Reference Installation wir-
ing section for correct connections
After disconnecting the power, correct the 
wiring problem and re-cycle power.  
 2) Power not online   1) Check  that the units main power is 
connected. 
     The  main  control  board  should  be 
operating normally
After  verifing  the  wiring  to  the  Room 
Controller 2, re-cycle the unit power. 
3) No 12 volts between P and G of 
terminal block. 
1) Check the installation of the J6 plug 
on the main control board.
After disconnecting the power, correct 
the wiring problem and re-cycle power. 
+12 volts applied to Room Control-
ler at the correct terminals and still 
does not operate
1) The Room Controller 2
      is damaged.
Change  the  Room  Controller    2  and 
re-cycle power.  
The data sent by the indoor unit are 
not displayed.
1) The connecting cable between the 
unit to the Room Controller2 is cut or 
not properly connected.
1) Check connection to J2 on the unit 
and on CRC2 “I” connector.
After disconnecting the power, correct 
the wiring problem and re-cycle power.
Icon A is displayed. There is no 
active button
1) Interference from another interface 
on the  CRC2 communication line.
1) Check that  the LED card is con-
nected.
Disconnect the LED card.
For Cassette units this should be made 
by disconnecting the black connector 
under the grille filter.
The following fault codes will be displayed next to temperature:
Code Description
A1
Air temperature sensor alarm
A2
Communication lost with terminal
A3
Terminal alarm
A1:  This alarm starts if the sensor detects a temperature lower 
than -17°C or higher than 63°C for more than 15 seconds.  The 
alarm stops when the temperature value returns and remains 
within the limits for more than 15 seconds.
A2:  This alarm starts if the control does not communicate with the 
terminal for 5 consecutive messages. The control works even 
in case of fault and the alarm stops as soon as it receives the 
answer from the terminal.
A3:  This alarm starts every time the terminal  sends an alarm 
message to the control (for more details on the alarms, refer to 
Control instructions on the machine). The control works even in 
case of fault and the alarm stops as soon as the cause for the 
Terminal alarm is detected and repaired.
Troubleshooting