Takagi 110U Indoor (T-KJr2U-IN) Installation Manual And Owner's Manual page 25

Easy-Link connection with allowable heaters
Gas In
Cold In
Only listed models on the table above can be combined together as an
CAUTION
Easy-Link System These models cannot be combined together with other
models not listed on the table above.
When the 510U (T-D2U) model is connected to other models listed above as
part of an Easy-link system with the
manufacturer.
WARNING
-General-
4 units
9008172005 (
Hot Out
TM-RE40), Contact the