York HIC4008B21S Installation And Maintenance Manual page 28

8. All electrical work should be performed in strict accordance with electrical schematics in the
"Installation and Maintenance Manual".
9. If Power Supply Voltage (208V/230V) is introduced into the Communication Line:
If 208V/230V are applied to the communication line at (Terminals 1 and 2 of TB2) by mistake, the fuse
on the PCB for the communication line will blow. In this case, perform the recovery work as shown in
the diagrams below.
a. Reconnect the wirings correctly.
b. Set the No.1 pin at DSW7 (on the PCB) to ON.
Upon PCB recovery after the fuse has been replaced, if 208V / 230V is reintroduced into the
communication line, the PCB will be seriously damaged and will not recover.
R
AC 208V/230V
5V
10. Wired Controller Connections
a. Wired Controllers at each unit for an individual operation setting
Indoor Unit
Outdoor Unit
Wired
Controller
b. Single Wired Controller for an individual operation setting
Outdoor Unit
Wired
Controller
c. Wired Controller connections between different refrigerant cycles
Outdoor Unit
Wired
Controller
24
S
A B 1 2
L1 L2
Incorrect Wiring
Indoor Unit
A B
Wired
Controller
Indoor Unit Indoor Unit
A B
Communication cables
for the wired controller
are necessary.
Indoor Unit Indoor Unit
A B A B
Wired
Controller
Individual
Simultaneous
(Thermo ON / OFF individually)
R S
L1 L2
AC 208V/230V
5V
Reconnect wirings correctly.
A B
A B
Indoor Unit Indoor Unit
A B A B
Individual
PCB
A B 1 2
DSW7
ON
OFF
1 2
Set No.1 Pin
at ON side.
Outdoor Unit
Wired
Controller
P5417054