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19
Fig. 30 —Typical Heat Recovery System Communication Wiring
P Q
X Y
X Y
MDC unit
outdoor unit
Centralized controller
HA HB
P Q
P Q
P Q
P Q
P Q
P Q
wired controller
HA HB
To No.1
indoor
To No.2
indoor
To No.3
indoor
To No.4
indoor
To No.1
indoor
To No.2
indoor
To Sub MDC
Main MDC unit
To outdoor
To outdoor
L1
L2
L3
L3
L3
L3
L4
L4
L5
L6
L7
L8
L9
L10
L11
Indoor unit 1#
HA HB
Indoor unit 2#
Indoor unit 3#
Indoor unit 4#
Indoor unit 5#
Indoor unit 6#
HA HB
HA HB
HA HB
HA HB
HA HB
Maximum wiring length
//IW$:*&RUH6WUDQGHG6KLHOG
/IW$:*&RUH6WUDQGHG6KLHOG
/IW$:*&RUH6WUDQGHG6KLHOG
/IW$:*&RUH6WUDQGHG6KLHOG
HA HB
HA HB
HA HB
HA HB
HA HB
HA HB
NOTE: Power from IDU
NOTE: 24 v. DC Power
(Field Supplied)
wired controller