American Water Heater NonCondensing UltraLow NOx Outdoor Natural Gas GT110UNE user manual

							21  Page
-Pressure relief valve-
The water heater has a high-temperature shutoff switch built in as a standard safety feature (called a 
Hi-Limit switch) therefore a “pressure only” relief valve is required.
•	This unit does not come with an approved pressure relief valve.
•	An approved pressure relief valve must be installed on the hot water outlet.
•	The pressure relief valve must conform to ANSI Z21.22 or CAN 1-4.4 and installation must follow local 
codes.
•	The discharge capacity must be at least 140,000 BTU/h for the 110U (T-KJr2U) model, 190,000 BTU/h 
for the 310U (T-K4U) model, and 199,000 BTU/h for the 510U (T-D2U) model.
•	The pressure relief valve needs to be rated for a maximum of 150 psi (1 MPa).
•	The discharge piping for the pressure relief valve must be directed so that the hot water cannot splash 
on anyone or on nearby equipment.
•	Attach the discharge tube to the pressure relief valve and run the end of the tube to within 6 in. 
(152 mm) from the floor.  This discharge tube must allow free and complete drainage without any 
restrictions.
•	If the pressure relief valve installed on the water heater discharges periodically, this may be due to a 
defective thermal expansion tank or defective pressure relief valve.
•	The pressure relief valve must be manually operated periodically to check for correct operation.
•	No valve must be placed between the relief valve and the water heater.
ELECTRICAL CONNECTIONS
All indoor models come with a power plug instead of a junction box.  The following procedure is for 
outdoor models only.
1. The water heater must be electrically grounded.  Do not attach the ground wire to either the gas or 
the water piping.
2. The water heater requires 120 VAC, 60 Hz electrical power supply that is properly grounded.
•	A proper disconnect (i.e. on/off switch, power plug, etc.) controlling the main power to the water 
heater must be provided for service reasons. (Must comply with local codes.)
•	Connect the power supply to the water heater exactly as shown in the wiring diagram.
3. A green screw is provided in the junction box to ground the connection.
4. Can be hardwired or wired to a plug-in.
5. The use of a surge protector is recommended in order to protect the unit from power surges.
Follow the electrical code requirements of the local authority having jurisdiction. 
In the absence of such requirements, follow the latest edition of the National 
Electrical Code ANSI/NFPA 70 in the U.S. or the latest edition of CSA C22.1 
Canadian Electrical Code Part 1 in CanadaWARNING
When servicing or replacing parts within the water heater, label all wires prior to 
disconnection to facilitate an easy and error-free reconnection.  Wiring errors can 
cause improper and dangerous operation.  Verify proper operation after servicing.CAUTION
Outdoor models only
Bottom	view	of	water	heaterView of electrical 
connections	of	water	heater
Ground
Connect
power supply
120VAC, 60HzGreen screw
Indoor models only
Installation
Installation Manual  
						

							22  Page
TEMPERATURE REMOTE CONTROLLER
-INCLUDED ACCESSORIES-

1.	 Take	off	the	 “Back plate” from the remote controller with a flat head screwdriver. (Fig. A and B)
2.	 Attach	 the	“Back plate” on the wall with the two provided screws. (Fig. B)
•	This remote controller is NOT waterproof 
     Do not install in high temperature environments, steamy conditions (such as a
     bath room), outdoors, in direct sunlight, or within the reach of children.
     Make sure the remote controller does not come into contact with water or oil.
•	Do not place the remote control wiring close to other wires from other 
products.
•	Do not extend the remote control wiring more than 400 ft. (122 m.)
CAUTION
Fig. BBack plate
3-1/4 inchesAttach the screws
Cut out the partition with pliers
Main body
Fig. A
Main body
Twist
Press and twist flat head 
screwdriver against the cutout.
Check that these items below are included with the remote controller.
Temperature
remote controller*ScrewsManualRemote controller cable
Qty: 1Qty: 2Qty: 1Qty: 1
-INSTALLATION-
Installation
Installation Manual
*9009069005 (TM-RE42)  
						

							23    Page
3.	 Tighten	the	two	"Fork terminals" beneath the two "Remote controller terminal" screws on
      the back of the main body. (Fig. C-1)
4.   Cut out the inlet for the remote controller cable from the bottom of the main body. (Fig. C-2)
5.	 Place	 the	“Main body” back on the "Back plate", with the "Remote controller cable" running 
      out of the bottom inlet.

Remote controller
      terminals
Fig. C-1
Two fork terminals
Remote controller cable
Inlet for the remote
  controller cable 
Cut out
Fig. C-2
1.	 Disconnect	 power	supply	from
      the water heater.
2.	 Take 	off	 the	 water	 heater’s	 front
      c o v e r.
3.	 Locate	 the	remote	 controller
      terminal.  (Refer to the Fig. D-1
      and D-2.)
4.	 Open	the	plastic	 cover	of	the
      remote controller, and then 
      attach the two fork terminals to
      connector base of the backside
      of the remote controller with 
      two screws.  Make sure the
      terminals are firmly fixed.
110U (T-KJr2U) and 310U (T-K4U) models
9009069005
(TM-RE42)
Front of remoteConnect other end to these terminals
Installation
Installation Manual
Fig. D-1   
						

							24   Page
5.	 Pull	the	 remote’s	 wires	through	 the	hole	 at	the	 bottom	 of	the	 water	 heater’s	 casing.
6.	 Properly	 attach	the	remote’s	 wires	to	the	 remote	 controller	 terminal	on	the	 computer	 board
      (No polarity).
	 * Do NOT jump or short-circuit the wires, or computer will be damaged.
7.	 Replace	Front	Cover	 securely.
8.	 Wires	 used	for	the	 remote	 controller	 connection	 must	be:
•	Minimum 20 gauge wire (No polarity)
•	Maximum 400 ft. (122 m) long
Installation
Installation Manual
9009069005
 (TM-RE42)
Front of remoteConnect other end to these terminals
510U (T-D2U) model
Fig. D-2  
						

							25    Page
EASY-LINK SYSTEM
(Available on the 510U (T-D2U) model only)
The 510U (T-D2U) model water heaters can be connected with other allowable heaters (see the 
table below) with communication cables to work as a multiple-unit manifold system.
•	The Easy-Link System allows up to 4 units to manifold together.
•	A communication cable (gray color) comes with each 510U (T-D2U) model.
You can manifold from 2 to 4 units without the need for a multi-unit controller.  A 4-unit system 
has full automatic modulation between 15,000 BTU/h and 796,000 BTU/h.
 
-Easy-Link Connection Procedures-
1. Make sure the power to the heaters are off.
2. Verify the DIPswitch set temperatures of all units within the system.  Every single water heater must 
be set to the same set temperature.  If an TM-RE42 remote controller is used, it should be installed to 
the “PARENT” unit.  The remote will set the temperature for the entire system.
3. Select one unit to be the “PARENT” unit.  The “PARENT” unit should be one of the end units.
4. “PARENT” unit:
 Locate the two banks of DIPswitches at the bottom left of the computer board of the unit that you 
select to be the “PARENT” unit.  Change DIPswitch No. 1 on the lower bank of DIPswitches to the ON 
position.  See the computer board diagram as shown in the next page.  Do not change any DIPswitches 
on any of the “CHILD” units.
•	The Easy-Link System is limited up to 4 units.  If you connect more than 4 
units, only the first 4 units will work as a part of the Easy-Link System.  The 
other additional units will not work.
•	Only listed models on the table above can be combined together as an 
Easy-Link System.  These models cannot be combined together with other 
models not listed on the table above.
CAUTION
-General-
Installation
Installation Manual
OFF
ON1
2
3 4
5
6234
5
The dark square is the direction the DIPswitch should be set to.
DIPswitch setting on the 510U (T-D2U)
       (Lower bank of DIPswitches) 
Gas In
Hot Out
Cold In
Easy-Link connection
with allowable heaters
T-K3
T-K3-Pro
510 model (T-D2-IN / T-D2-OS)
510U model (T-D2U-IN / T-D2U-OS)*
*If the 510U (T-D2U) models are incorporated in an Easy-Link Sytem with the other models in the table 
above, change DIPswitch No.6 on the lower bank of all the 510U (T-D2U) computer boards to the “ON” 
position.  
						

							26   Page
5. Between the “PARENT” and the “CHILD-1” units:
 Connect the “PARENT” connector of the “PARENT” unit to the “1” connector of the “CHILD-1” unit 
using the supplied linking cable.
6. Between the “CHILD-1” and the “CHILD-2” units:
 Connect the “2” connector of the “CHILD-1” unit to the “1” connector of the “CHILD-2” unit.
7. Between the “CHILD-2” and the “CHILD-3” units:
 Connect the “2” connector of the “CHILD-2” unit to the “1” connector of the “CHILD-3” unit.
8. Verify that all cables are connected like the diagram below (B).
9. Turn on power to the “PARENT” unit.  The remote controller will display “1”.
 Turn on “CHILD-1”.  When the remote controller displays a number, turn on “CHILD-2”.
 When the remote controller displays a number, turn on “CHILD-3”.
 Make sure the remote controller displays each unit #. (Refer to p.43.)  The numbering system automati-
cally allocates the unit # to each water heater in the Easy-Link System, in accordance with the table 
below.
(A) 510U (T-D2U) model Computer board
(B) Basic diagram of connections between the Easy-Link System units
NOTE: The dark squares indicate the direction the DIPswitches should be set to.
Type of unitUnit # of easy-link
Parent1
Child2, 3 or 4
PARENT
Communicaon cable
Connector s
Lower bank of
DIP switches
OFF
ON
1111
2222
PA
RENT
PA
RENT
PA
RENT
1
2
3 456
Connector
s Connectors Connectors
1
2
3 4
56
OF
F
ONOF
F
ON
1
2
3 456
OF
F
ON
1
2
3 4
56
Lower bank of
DIP
switches Lower bank of
DIP
switches Lower bank of
DIPs
witches
PARENT unitCHILD-1 unitCHILD-3 unitCHILD-2 unit
Remote controller
To change the DIPswitch 
settings for the Easy-Link 
System, locate the bank of 
DIPswitches at the bottom 
left of the computer board.  
Do not adjust the upper 
bank of  DIPswitches.
Easy-Link / 
Multi-Unit 
connectors 
are next to 
the computer 
board.
  Lower bank of DIPswitches
Upper bank of DIPswitches
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							27    Page
(C) Examples of incorrect settings and /or connections
      CASE 1: Wrong DIPswitch setting on the "PARENT" unit
      CASE 2: Wrong connections between the "PARENT" unit and the 
                   "CHILD-1" unit
•	If you connect the “1" (or "2") connector of the “PARENT” unit to the “PARENT" (or "1") 
connector of the “CHILD-1” unit, the system will not work as an Easy-Link System.  The units will 
operate as individual units.
OR
PARENT unitCHILD-1 unit
Wrong	Setting
Communicaon cable\3
$POOFDUPST$POOFDUPST
OFF
ON
12
3\f5
6
Lo\ber bank o
f
DIPs \bitches
OFF
ON
12
3\f56
Lo\ber bank o
f
DIPs \bitches
PARENT
1
2
PA RENT
1
2
PARENT unitCHILD-1 unit
Wrong 
Connections
Communicaon cable\k
Connector s
Connector s
Lower bank o \f
DIPs witc\bes
12
34
56
OF
F
ONOF
F
ON
1
2
3 45
6
Lower bank o
\f
DIPs witc\bes
PARENT
1
2
PA RENT
1
2PARENT unitCHILD-1 unit
Wrong 
Connections
Communicaon cable\N
Connector s Connectors
OFF
ON
\f2
34\b6
Lower bank o
f
DIP switches
Lower bank o
f
DIP switches
\f2
34\b 6
OF
F
ON
P
AREN T
\f
2
P AREN T
\f
2
•	A remote controller is not required for an Easy-Link System, however, it does 
provide for more temperature options and ease of maintenance.
•	If a remote controller is used, the temperature on all the units in the system 
will automatically be set to the same temperature that is set on the remote.
NOTICE
•	Unless you change DIPswitch No. 1 
of the “PARENT” unit to the “ON” 
position, the system will not work 
as an Easy-Link System.  The units 
will operate as individual units.
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							28  Page
CASE 3: Wrong connections between the "CHILD-1" unit and the "CHILD-2" unit
•	If you connect the “PARENT” connector of the “CHILD-1” unit to the “1” connector of the 
“CHILD-2” unit, the “CHILD-2” unit will operate as an individual unit, and will not be part of the 
Easy-Link System.
      CASE 4: Remote controller connected to incorrect unit
•	Remote controller has to be connected to the “PARENT” unit.  If the remote controller is 
connected to a “CHILD” unit, it will only control that particular individual “CHILD” unit and will 
not control the Easy-Link System as a whole.
     
Connecting two “PARENT” connectors together from two separate units may 
damage the computer board.  The communication cable has a female end and 
a male end so it’s impossible to have a PARENT-to-PARENT connection with the 
communication cable.  Do not splice or modify connectors.WARNING
PARENT unitCHILD-1 unitCHILD-2 unit
Wrong 
Connections
Communicaon cable\k
Connectors Connectors Connectors
Lower bank o \f
DIPs witc\bes
12
3456
OF
F
ONOF
F
ON
12
3456
Lower bank o
\f
DIPs witc\bes
OFF
ON
1
2
3 45
6
Lower bank o \f
DIPs witc\bes
PARENT
1
2
PA RENT
1
2
PA RENT
1
2
PARENT unitCHILD-1 unit
Remote controller
Wrong	Connections
Communicaon cabl e
2
1
2
1
PARE\fT
PA
RE\fT
Connector \bC onnector\b
OFFO\f
1
2
3 4
56
Lower bank o
f
DIP\b witche\b
OFFO\f
1
2
3 4
56
Lower bank of
DIP\b
witche\b
Installation
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							29    Page
MULTI-UNIT SYSTEM
Multiple 510U (T-D2U) models can be combined for a Multi-Unit System, along with the multi- 
unit controller (Parts 9008300005 (TM-MC02)) and remote controller (9008172005 (TM-RE40)).  
Each set of multi-unit controller and remote 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 15,000 BTU/h 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 and temperature remote controller wiring:
•	The dark squares should not need adjustment.
•	This is the connection diagram between 510U (T-D2U) and multi-unit controller 
for 2 to 20 water heaters.  Above 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 (refer to p. 26) or 18 gauge wire cables.  The total cable 
length can be up to 250 ft. (76.2 m) long.
For detailed instructions on the multi-unit controller, refer to the
instructions that are packaged with the multi-unit controller.
OFFON
111
222
PARENTPARENT PARENT
1
2
3
4 5
6
Connectors
Connectors Connectors
OFFONOFFON
Lower bank of
DIPswitches Lower bank of
DIPswitches Lower bank of
DIPswitches
1
2
3
4 5
6
1
2
3
4 5
6
Communication cable
Remote controller cable
Unit 1Unit 2Unit 3
Remote controller
9008172005 (TM-RE40)
Terminals for
water heaters
9008300005
 (TM-MC02)
Remote controller
terminals
9008300005
 (TM-MC02)
  510U
(T-D2U)
Cold INHot Out
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							30  Page
APPLICATIONS
-Space-Heating Applications-
-Recirculation-
*The recirculation pump is to be controlled by:
-Dual-set aquastat (recommended w/timer)
*The recirculation pump is to provide no less than 2 GPM (7.5 L/min) and no more than 4 GPM (15 L/min) through
  each activated unit in the system.
•	In order to purge air in water pipes within a closed-loop system, an air vent 
and air separator should be installed in the system.  Required circulation 
flow rates are labeled next to each application diagram.  These flow rate 
requirements must be followed.
•	Toxic chemicals used in boiler treatments such as alcohol, glycerol and glycol 
groups must not be introduced into the system if the system incorporates an 
open-loop potable water system.
•	The water heater can be used to supply potable water and space heating and 
shall not be connected to any heating system or component(s) previously 
used with non-potable water where any chemicals were added to the water 
heating appliances.
•	When the system requires water for space heating at temperatures higher 
than required for other uses, a means such as a mixing valve shall be installed 
to temper the water for those other uses in order to reduce scald hazard 
potential.
•	Water temperature over 125 °F (52 °C) can cause severe burns instantly or 
death from scalding.
•	Chemicals such as diluted Glycol can be used for radiant floor, Hydro/fan coil 
air or Baseboard heating only.  The diluted solution of glycol must contain 
between 25 and 55 % of Glycol.  Be aware that in closed-loop glycol systems, 
low pressure in the heat exchanger can cause low-temperature boiling, 
resulting in excessive noise and damage to the water heater.  Consult with the 
glycol maker for specifications prior to use.
WARNING
Air vent
Hot	water	outlet	to	fixtures
Recirculation
pumpAirseparator
SCheck valve
Check valve
Y-Strainer
Cold water inlet
Expansion tank
Gas supply
Ball valves
Unions
Hot water outletCold water inletGas inlet
Pressure relief valve
This is a concept drawing only.
Applications
Installation Manual