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16
Fig. 27 —Typical Heat Recovery System Communication Wiring
34
;<
;<
Main MDC unit
MDC unit
outdoor unit
Centralized controller
34
34
34
34
34
34
wired controller
+$+%
7R1R
LQGRRU
7R1R
LQGRRU
7R1R
LQGRRU
7R1R
LQGRRU
7R1R
LQGRRU
7R1R
LQGRRU
7RRXWGRRU
7R6XE0'&
7RRXWGRRU
L1
L2
L3
L3
L3
L3
L4
L4
L5
L6
L7
L8
L9
L10
L11
Indoor unit 1#
Indoor unit 2#
+$+%
+$+%
+$+%
+$+%
+$+%
+$+%
Indoor unit 3#
Indoor unit 4#
Indoor unit 5#
Indoor unit 6#
wired controller
+$+%
Maximum wiring length
L1+L2 < 3937 ft 18AWG, 2-Core Stranded Shield
L3 < 3937 ft 18AWG, 2-Core Stranded Shield
L4 < 3937 ft 18AWG, 2-Core Stranded Shield
L5 < 3937 ft 18AWG, 2-Core Stranded Shield
L6+L7+L8+L9 < 820 ft 18AWG, 2-Core Stranded Shield
L10+L11< 820 ft 18AWG, 2-Core Stranded Shield