Rinnai CNTRLDRCINW Operation And Installation Manual page 9

One controller to multiple units
For some units, one wired controller can support multiple units (a
maximum of 16).
For configuration of multiple indoor units loom connection is polarity
sensitive and HA must connect to HA on all indoor units, the same
applies to HB. In group control there will be no error displayed on the
wired controller.
Controller 1
Indoor unit 1
HA HB
Total length 40 m maximum
HA
HB
Indoor unit 2
HB
HA
Indoor unit n
Max. 16
HA HB
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