12
Supplemental heat/aux heat status — 
1. Slide to choose the IDU address.
2. Touch the Save icon to send current address to the IDU.
Brand choice setting — 
1. Choose “Brand choice setting” on the “Service”
interface.
2. Select either Carrier or Bryant.
1. To use the firmware upgrade function, save the firm-
ware file and verification file in the root directory of
the USB disk.
Updatin
g the firmware will restore the controller parameters to 
factory  settings while  applying  changes associated  with  the 
firmware version.
Keep the power connected during the update process.
2. Insert the USB disk into the controller.
3. Choose “Firmware update” on the “Service” interface.
4. Touch the “Update” icon.
The available range of IDU address is #0 – #63.
Fig. 46 —Supplemental Heat/Aux Heat Status
These settings are used when the IDU is controlling a field-
provided auxiliary heat source via its ACB interface contact 
output.
Turning  Aux  Heat  Status  on  enables  this  function;  Status 
Configuration selects the amount of temperature differential 
before triggering aux. heat output; Time Delay selects 
amount of time before triggering aux heat output; and 
turning Fan Status on commands the IDU fan to run while 
aux heat output is active.
Setting the indoor unit address — The IDU 
communication address can be set only when the wired 
controller is connected to one IDU. 
Fig. 47 —Indoor Unit Address
Fig. 48 —Brand Choice Setting
Fig. 49 —Brand Selection
“Test” is a o
ne-time setting and will not be saved. The brand 
needs to be selected again upon the next start-up.
“Permanent” indicates permanent setting and will be 
effective permanently.
Firmware update — A USB disk in NTFS or FAT 
format is required.
Fig. 50 —Firmware Update