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

							41    Page
MAINTENANCE AND SERVICE
•	Clean the cold-water inlet filter. (Refer to Unit draining and filter cleaning section in this page.)
•	Be sure that all openings for combustion and ventilation air are not blocked.
•	The venting system should be checked annually for any leaks, corrosion, blockages or damage.
•	The burner should be checked annually for dust, lint, grease or dirt.
•	Keep the area around the water heater clear.  Remove any combustible materials, gasoline or any 
flammable vapors and liquids.
•	In accordance with all local codes and common safety practices, water discharged from the pressure 
relief valve can cause severe burns instantly from scalding.  DO NOT touch the pressure relief valve.
•	If the relief valve discharges periodically, it may be due to thermal expansion in a closed water supply 
system.  Contact the water supplier or local plumbing inspector on how to correct this situation.
•	Visual check of burner flames (see below) through the burner window in the burner assembly located 
at the middle of the water heater.
The manufacturer recommends having the unit checked once a year or as necessary by a licensed 
technician.  If repairs are needed, any repairs should be done by a licensed technician.
UNIT DRAINING and FILTER CLEANING
Turn off the electrical power supply and close the manual gas shutoff valve 
and the manual water control valve before servicing.
WARNING
1. Close the manual gas shutoff valve.
2. Turn off power to the unit and wait a couple of seconds. 
Turn on again.
3. Wait 30 seconds, and then turn off power to the unit, 
yet again.
4. Close the water shutoff valve.
5. Open all hot water taps in the house.  When the 
residual water flow has ceased, close all hot water taps.
6. Have a bucket or pan to catch the water from the unit’s 
drain plugs.  Unscrew the two drain plugs (large and 
small) to drain all the water out of the unit.
7. Wait a few minutes to ensure all water has completely 
drained from the unit.
8. Clean the filter: Check the water filter located within 
the cold inlet.  With a tiny brush, clean the water 
filter of any debris which may have accumulated and 
reinsert the filter back into the cold water inlet.
9. Securely screw the drain plugs back into place. 
     Hand- tighten only.
Drain plugwith Filter(Large)
Gas valve
Drain plug(Small)
Water valve
Satisfactory
Blue	flame
Satisfactory
Blue	flame
Burner
Flame blowing up
UnsatisfactoryBurner
Normal Operation
Owner's Guide  
						

							42  Page
WATER CONNECTIONS
All pipes, pipe fittings, valves and other components, including soldering materials, must be suitable for 
potable water systems.
1. A manual shutoff valve must be installed on the cold water inlet to the water heater between the main 
water supply line and the water heater.
2. In addition, a manual shutoff valve is also recommended on the hot water outlet of the unit.  If the 
water heater is installed within, or subjected to, a closed loop water system, a thermal expansion tank 
must be installed.
-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) models, 190,000 BTU/h 
for the 310U (T-K4U) models, and 199,000 BTU/h for the 510U (T-D2U) models.
•	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.

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).
TROUBLESHOOTING
GENERAL
PROBLEMSOLUTIONS
TEMPERATURE and AMOUNT OF HOT WATER
It takes long time to 
get hot water at the 
fixtures.
•	The time it takes to deliver hot water from the water heater to your 
fixtures depends on the length of piping between the two.  The longer 
the distance or the bigger the pipes, the longer it will take to get hot 
water.
•	If you would like to receive hot water to your fixtures quicker, you may 
want to consider a hot water recirculation system. (p. 30)
The water is not hot 
enough.
•	Compare the flow and temperature.  See the charts on p. 54.
•	Check cross plumbing between cold water lines and hot water lines.
•	Is the gas supply valve fully open? (p. 32)
•	Is the gas line sized properly? (p. 19)
•	Is the gas supply pressure enough? (p. 20)
•	Is the set temperature set too low? (p. 36-37,39)
The water is too hot.•	Is the set temperature set too high? (p. 36-37,39)
The hot water is not 
available when a 
fixture is opened.
•	Make sure the unit has 120 VAC, 60 Hz power supply.
•	If you are using the remote controller, is the power button turned on?
•	Is the gas supply valve fully open? (p.32)
•	Is the water supply valve fully open? (p. 32)
•	Is the filter on cold water inlet clean? (p. 41)
•	Is the hot water fixture sufficiently open to draw at least 0.5 GPM 
     (1.9 L/min) through the water heater? (p. 36)
•	Is the unit frozen? (p. 40)
The hot water turns 
cold and stays cold.
•	Is the flow rate enough to keep the water heater running? (p. 36)
•	If there is a recirculation system installed, does the recirculation line have 
enough check valves? (p. 30)
•	Is the gas supply valve fully open? (p. 32)
•	Is the filter on cold water inlet clean? (p. 41)
•	Are the fixtures clean of debris and obstructions?
•	Check if the flow rate is too low. (p. 36)
Fluctuation in hot 
water temperature.
•	Is the filter on cold water inlet clean? (p. 41)
•	Is the gas line sized properly? (p. 19)
•	Is the supply gas pressure sufficient? (p. 20)
•	Check for cross connection between cold water lines and hot water lines.
Troubleshooting
Owner's Guide  
						

							43  Page
PROBLEMSOLUTIONS
WATER HEATER
Unit does not ignite 
when water goes 
through the unit.
•	Is the flow rate over 0.5 GPM (1.9 L/min)? (p. 36)
•	Check for the filter on cold water inlet. (p. 41)
•	Check for reverse connection and cross connection.
•	If you use the remote controller, is the power button turned on?
•	Check if the inlet temperature is too high.
The fan motor is 
still spinning after 
operation has stopped.
•	This is normal.  After operation has stopped, the fan motor keeps 
running from 15 to 70 seconds in order to re-ignite quickly, as well 
as purge all the exhaust gas out of the flue.
Unit sounds abnormal 
while in operation
•	Contact the manufacturer at 1-877-737-2840.
Remote controller
Remote controller does 
not display anything 
when the power 
button is turned on.
•	Make sure the unit is supplied with power.
•	Make sure the connection to the unit is correct. (p. 23-24)
-9009069005 (TM-RE42)-
If the STAND BY LED lights up, the 
remote controller has been 
turned ON.  When the unit has not
operated for five minutes or more, 
the display turns off to conserve
energy.
An ERROR code is 
displayed.
•	Please see p. 44-46.
EASY-LINK SYSTEM
510U (T-D2U) model only
How are the unit 
numbers assigned?
•	For an Easy-Link System, the Parent unit is always labeled #1 and all 
other subsequent Child units are numbered randomly.
•	To check which numbers are assigned to which Child units, push the 
button on the computer board of any Child unit as shown below. 
The unit number will be displayed on the remote controller.  (Refer 
to p. 25-28.)
Button	to	check	unit	numbers
When the remote 
controller turned 
ON, STAND BY 
LED is lit.
Troubleshooting
Owner's Guide  
						

							44  Page
ERROR CODES
-General-
•	The units have self-diagnostic function for safety and convenience when troubleshooting.
•	If there is a problem with the installation or the unit, the error code will be displayed on the remote 
controller.
•	Consult with the table on the following pages for the description of each error code.
-Single unit Installations-
Example: If your unit has the “321” error code (which signifies an inlet thermistor failure)
•	Remote controller 9009069005 (TM-RE42): “321” will be displayed on the screen in its entirety.
•	Water heater: The green LED on the computer board will be blinking two times.
-Easy-Link System-
(For the 510U (T-D2U) model only)
Error codes will be displayed differently with units installed within an Easy-Link System, not only to show 
what the error code is, but to also indicate which unit within the system has the error code.  Below is a 
sample of how the same error code is displayed in an Easy-Link System.
Example: If Unit #2 has the “321” error code (inlet thermistor failure)
•	Remote controller 9009069005 (TM-RE42): “321” and "2" will intermittently flash on the display.  And
                                                                        \
      it shows that Unit #2 has the error.
Troubleshooting
Owner's Guide
Green LED
110U (T-KJr2U) and 310U (T-K4U) models 
Error code on the computer board
Error code on the remote 
controller 9009069005 (TM-RE42)
Unit #Error code
•	Parent unit: This unit will not display anything,as 
the error code does not pertain to it.
•	Unit #2: The green LED on the computer 
board will be blinking two times, just like in the 
single unit example.
•	Unit #3 and #4: These units will not display 
anything, as the error code does not pertain to 
them.
Error code
510U (T-D2U) model
Green LED
9009069005 (TM-RE42)
Unit #1
PARENT
Unit #2
 CHILD
Unit #4
 CHILD
Unit #3
 CHILD  
						

							45  Page
-Fault Analysis of Error Codes-
If the error code is displayed on the computer board of the water heater or remote controller, please 
check the following.  After checking, consult with the manufacturer.
Troubleshooting
Owner's Guide
RemoteGreen
 LED
Malfunction
descriptionDiagnosis
031One TimeIncorrect DIPswitch 
setting
•	Check the DIPswitch settings on the PCB (Part #701).
101Five TimesWarning for the 
“991” error code 
•	Check the gas type of the water heater.
•	Check if there is any blockage in the intake air and/
or exhaust.
•	If the water heater is installed as a direct-vent 
system, check whether there is enough distance 
between the intake air terminal and the exhaust 
terminal.
•	Check the altitude/elevation of area of where the 
water heater is installed.
•	Check if there is grease and/or dirt in the burner (Part 
#101) and the fan motor (Part #103), especially if the 
water heater has been installed in a contaminated area.
111Three TimesIgnition failure•	Check if the Hi-limit switch (Part #412) is properly 
functioning.
•	Check for connection/breakage of wires (Part #413, 
708, 709, 710, 712), burn marks on the computer board 
(Part #701), and/or soot on the flame rod (Part #108).
•	Check if there is a buzzing spark ignition sound 
coming from the burner (Part #101) when water 
heater prepares for combustion.
•	Listen for the double “clunk” sound coming from gas 
valve assembly (Part #102) when water heater goes 
into combustion.
•	Check if there is leaking from heat exchanger (Part #401).
121Three TimesLoss of flame•	Check if the Hi-limit switch (Part #412) is properly 
functioning.
•	Check for connection/breakage of wires (Part #413, 
708, 709, 710, 712), burn marks on the computer 
board (Part #701), and/or soot on the flame rod 
(Part #108).
•	Check if there is leaking from heat exchanger (Part #401).
311Two TimesOutlet thermistor 
failure (110U 
(T-KJr2U) / 310U 
(T-K4U) models 
only)
Heat exchanger 
thermistor failure 
(510U (T-D2U)) 
model only)
•	Check for connection/breakage of wires and/or 
debris on thermistor (Part #407, 408, 411, 715).
321Two TimesInlet thermistor 
failure
331Two TimesOutlet thermistor 
failure 
(510U (T-D2U)) 
model only)  
						

							46  Page
Troubleshooting
Owner's Guide
RemoteGreen 
LED
Malfunction
descriptionDiagnosis
391Two TimesAir-fuel ratio rod 
failure
•	Check for connection/breakage of wires (Part #709) 
and/or soot on the AFR rod (Part #108).
441Two TimesFlow sensor failure 
(Easy-Link System 
only)
•	Check for connection/breakage of wires and/or 
debris on the flow sensor impeller (Part #402).
510Six TimesAbnormal main gas 
solenoid valve
•	Check for connection/breakage of wires (Part #708) 
and/or burn marks on the computer board (Part 
#701).
551Six TimesAbnormal gas 
solenoid valve
•	Check for connection/breakage of wires (Part #708) 
and/or burn marks on the computer board (Part 
#701).
611Four TimesFan motor fault•	Check for connection/breakage of wires, dust buildup 
in the fan motor (Part #103) and/or burn marks on 
the computer board (Part #701).
•	Check for frozen/corrosion of connectors (Part #103).
651Four TimesFlow adjustment 
valve fault (Easy-
Link System only)
•	Inspect the flow adjustment valve (Part #402), for  
connection/breakage of wires, locked motor drive 
due to scale buildup, and/or water leakage.
661Four TimesBypass valve fault
(510U (T-D2U)) 
model only)
•	Inspect the bypass valve (Part #403), for  connection/
breakage of wires, locked motor drive due to scale 
buildup, and/or water leakage.
701One TimeComputer board fault•	Check for connection/breakage of wires (Part #714).
711One TimeGas solenoid valve 
drive circuit failure
•	Refer to the 111 and 121 error codes.
721Six TimesFalse flame 
detection
•	For indoor models, check if condensate drain is 
installed on the vent collar of the water heater.
•	Check if there is leaking from heat exchanger (Part 
#401).
741N/AMiscommunication 
between water 
heater and remote 
controller
•	Check the model type of the remote controller.
•	Inspect the connections between the water heater 
and remote controller.
•	Check the power supply of the water heater.
761N/AMiscommunication 
in Easy-Link system
•	Check if the connections between the parent unit 
and the child units are correct. Refer to p. 25-28.
991Five TimesImperfect 
combustion
•	Check the gas type of the water heater.
•	Inspect the environment around the water heater. 
Determine how long the unit has been installed.
•	Check the altitude/elevation of the area of where 
the water heater is installed.
•	Check if there is any blockage in the intake air and/
or exhaust. 
•	If the water heater is installed as a direct-vent system, 
check whether there is enough distance between the 
intake air terminal and the exhaust terminal. 
•	Check if there is grease and/or dirt in the burner (Part 
#101) and the fan motor (Part #103), especially if the 
water heater has been installed in a contaminated 
area.  
						

							47  Page
COMPONENTS DIAGRAM
Indoor modelOutdoor model
Case assembly
Temperature remote controller
721
001
004
052003
052
007
002
051
050
052
005
704
002
001
702
704
006
717
Components Diagram
Owner's Guide  
						

							48  Page
510U (T-D2U) model
703
121
705
053
706
704
705
110U (T-KJr2U) and
310U (T-K4U) models
701705
103
402
402
715
707
715
403
714
709
708
711
705
103
709
402
402
711
707
714
407
408
708
716716
701
061
Computer board assembly
Surge box assembly
Components Diagram
Owner's Guide  
						

							49  Page
Components Diagram
Owner's Guide
Burner assembly
113
114
150
057119
151
118055
401
401
153
154
053
152
713
056
107106
108
060
109
111711
112
052
101
401
116
116
115
110
053
053
062
060
122053
060
060
104
105
123
708
711
711
117
719
052
055
053
054
102
709
714
063
707
103
062
720
117
Burner assembly
Manifold 
assembly
Exhaust section (Outdoor model)  
						

							50   Page
Components Diagram
Owner's Guide
Water Way assembly
463
413453
451
403
456
460
458
462
450414
459
454
402460456
461
458404
415
407
454
405
457
406
410455
408456454
460
409
C
452
411
414
451414
412
058
401
BA
B
A
D
052059
D
C
Bypass section
(510U (T-D2U)model)
510U (T-D2U)
     model
Water outlet section
Water inlet section
To Water
inlet section
To Water
outlet section