Installation Sheet

33 Page
MULTI-UNIT SYSTEM
Multiple 540 (T-H3) models can be combined for a Multi-Unit system, along with the multi unit
controller (Parts 9008300005 (TM-MC02)). The multi-unit controller can control from 2 units to 20
units for commercial or residential applications. For a 20-unit system, the computer can modulate
between the usages of 13,000 BTU/h (Propane) or 15,000 BTU/h (Natulal gas) to 4.0 Million BTU/h.
An individual cut-off switch is recommended for each unit in a multi-unit system for the purpose
of maintenance.
Multi-Unit System Connection Diagram
Multi-unit controller with the remote controller wiring:
• The dark squares should not need adjustment
• This is the connection diagram between 540 (T-H3) and multi-unit controller for
2 to 20 water heaters. As shown is a sample for 3 water heaters.
• The Multi-unit controller automatically allocates the unit # (1-20) to each water
heater that is part of the Multi-unit system.
• InaMulti-Unitsystem,connectthe“[1]”connectorandthe“[2]”connectorwith
thecommunicationcable.(Refettop.9).Orthecablesuse18gagewireandcan
be up to 250 ft. (76.2 m) long.
For detailed instructions to the mult-unit controller, refer to the
instructions that are packaged with the multi-unit controller.
OFF
ON
1 1
1
2 2
2
PARENT
PARENT
PARENT
1
2
3
4
5
6
Connectors Connectors Connectors
OFF
ON
OFF
ON
Lower bank of
DIPswitches
Lower bank of
DIPswitches
Lower bank of
DIPswitches
1
2
3
4
5
6
1
2
3
4
5
6
Communicaon cable
Remote controller cable
Unit 1
Unit 2 Unit 3
Remotecontroller
Terminals for
water heaters
9008300005
(TM-MC02)
Remotecontroller
terminals
Cold IN
Hot Out
540
(T-H3)
9008300005
(TM-MC02)