If a indoor unit needs to be removed from a system for repairs or replacing , if its a heat recovery unit , you will need to find the port it connects to on the MCU and make that dip swich off if its first gen equipt. , if its second gen equip. you would follow the same procedure as a Heat Pump , you would power off the Indoor unit and reduce the quanity at the outdoor unit by 1 and press the K3 button for a reset , first gen OD unit will have rotary switches that you would dial back 1 , next gen Press (K1+K2) for 2
seconds , then K1 AND K4 to reduce the number of ID units , then K2 for 2 seconds to save .
Making a Sub a Main outdoor unit .
Remove OF1/2 from the Sub and connect it to F1/2 terminals on the Sub , remove F1/2 and OF1/2 from the main and wire nut them togethor , set up the main control board at the Sub to match the main , number of id units and MCU'S if its a HR this makes the sub unit , Make sure the K5,6,7&8 DIP SWS Are in the on pos . if you have another sub unit you will have to make it the first sub if not already , the K8 sws will be off , this will make the sub the Main , always press K3 for a reset , if this is next gen OD unit you will have to set quanities in the now main , using the K1/K2 buttons for 2 sec. to set id units and Mcu's .
Reference the Air-source Manual for programming the OD unit . Control section.