American Water Heater NonCondensing Outdoor Natural Gas GT910NIE User Manual

							Gas Tankless Water Heater  
910 / 910 ASME  
(T-M50 / T-M50 ASME) Models 
 Suitable for combination potable water heating  
  and space heating.  Please refer to local codes for  
space- heating compliance.  
 
 
  
 
 
 
 
-Do not store or use gasoline or other 
flammable vapors and liquids in the vicinity 
of this or any other appliance. 
- WHAT TO DO IF YOU SMELL GAS  
•   Do not try to light any appliance.  
•   Do not touch any electric switch, do not 
use any phone in your building . 
•  Immediately call your gas supplier from 
a neighbors phone. Follow the gas 
suppliers instructions.  
•  If you cannot reach your gas supplier, 
call the fire department.  
- Instal lation and service must be performed 
by a qualified installer, service agency or 
the gas supplier.  
 
 
 
 
910 / 910 ASME (T -M50/T- M50 ASME)  
On-Demand  Water Heater  
Installation Manual and Owner’s Guide  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
                               
 
                     
 
 
 
 
 
 
 
 
 
 
 
 
 
       FEATURING  
•   ENDLESS HOT WATER  
•   ON -DEMAND  USAGE 
•   COMPACT, SPACE SAVING  
•   ENE RGY CONSERV ATION 
•   COMPUTE RIZED SAFETY  
•   NO PILOT LIGHT  
•   EASY- LINK SYSTEM  
•   Complies with  natural gas  Low NOx 
Emissions of  40 ng/J or 55 ppm.  
 
If you have any questions, please 
call or write to: 
500 Tennessee W altz Parkway 
Ashland City , TN  37015 
Toll Free: 1 -877-737-2840  
 
ANSI Z21.10.3・CSA 4.3  
If the information in these 
instructions is not followed 
exactly, a fire or explosion 
may result causing property 
damage, personal injury or 
death. 
WARNING 
HLW 
For supplying  
potable hot water 
ASME model ONLY  
						

							 - 2 - 
          CONTENTS  
 
 
 
 
NOTE 
*All references to the  910 (T -M50)  also refer to the   
  910  ASME  (T-M5 0 ASME) model . 
* Check the rating plate to ensure this product 
matches your specifications.  
 
 
 
 
 
 
 
 
SPECIFICATIONS 
Natural Gas Input  
(Operating Range)  Min: 15,000  Btu/h 
Max:  380,000  Btu/h
 
Propane Input  
(Operating Range)  Min: 15,000 Btu/h 
Max:  380,000  Btu/h
 
Gas Connection  1” N PT 
Water Connections 1” N PT 
Water Pressure 15  - 150 psi  * 
Natural Gas  
Inlet Pressure  Min.  4.0” WC   
Max . 10.5” WC
 
Propane  
Inlet  Pressure  Min.  8.0” WC   
Max . 14.0 ” WC
 
Manifold Pressure ** Natural: 2.8” WC  
Propane:  3.8” WC
 
Weight 102  lbs. 
Dimensions H25.3” ×W 24.8 ”× D11.8 ” 
Ignition Electric Ignition  
Electric 
Supply 120 VAC / 60  Hz  
Consumption  Operation
 
178 W 
(1.48A)  
Standby  16 W 
(0.13A)  
Freeze-
Protection  271 W 
(2.26A)  
SPECIFICATIONS………………………. 
INTRODUCTION………………………… 
SAFETY GUIDELINES……………….... 
INSTALLATION………………………….. 
    General…… …………………………… 
     Included  Accessories…….……………  
     Warning for Installations ……………… 
     Outdoor Installation……… ……………  
    Indoor Installation…………………......  
    Direct Intake Vent System…………….  
    Venting Instructions………………......   
    Gas Supply / Gas Pipe Sizing………..  
    Water Connections……………………  
    Pressure Relief Valve…………………  
    Electrical Connections……………......  
    Remote Controller Connection……… 
    Pump  Control  Connections ......……. ..  
    Pump Control Mode…………………… 
    Easy -Link System……………………… 
     Multi -Unit System……………………… 
    Initial Operation………………………..  
NORMAL OPERATION…………………. 
    Normal Operation…………………......  
    Flow…………………………………….. 
    Freeze Protection System…………...   
    Temperature Settings…………………. 
    Maintenance and Service……………. 
GENERAL  TROUBLE SHOOTING… ….. 
 OPERATING SAFETY ……………… ...… 
APPLICATIONS………………………......  
     Re -Circulation …………….... ...............  
     Dual -Purpose Heating……………… ... 
ADDITIONAL CLEARANCES …………… 
OPTIONAL ITEMS…… …...……………..  
COMPONENTS DIAGRAM…………….  
PARTS LIST……………………………… 
OUTPUT TEMPERATURE CHART…… 
LIMITED WARRANTY………………....... 
2 
3 
5 
6 
7 
7 
8 
9 
10 
11 
12 
16 
19 
19 
20 
21 
22 
23 
24 
27 
29 
30 
30 
32 
32 
33 
34 
35 
38 
40 
40 
41 
42 
43 
44 
48 
51 
51 
 
The manufacturer reserves the right to discontinue, or change at any time, 
specifications or designs without notice and without incurring obligations.  
*40 psi or above is recommended for maximum flow. 
**The Manifold Pressure is the factory setting and 
generally  should not need adjustment.  
						

							 - 3 - 
INTRODUCTION 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   
 
   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1. A hot water tap is turned on. 
2.  Water enters the heater.  
3.  The water flow sensor detects the water flow.  
4.  The computer automatically ignites the burner.  
5.  Water circulates through the heat exchanger and then gets hot.  
6.  The c omputer will modulate  the gas supply valve and water flow to produce  the right 
amount of hot wat er at the correct temperature.  
7. When the tap is turned off, the unit shuts down. 
*This diagram illustrates 
tankless water heater 
design concepts only  and is 
not accurate  to the  water 
heater ’s  physical  
description. 
• This manual provides information necessary for the installation, operation, and 
maintenance of the water heater.  
 
 • The model description is listed on the rating plate which is attached to the front cover of 
the water heater.  
 • Please read all installation instructions completely before installing this product.  
 
• If you have any problems or questions regarding this equipment, consult with the 
manufacturer or its local representative.  
                    
 • This equipment is an on-demand, tankless water heater designed to efficiently supply 
endless hot water for your needs. 
 • The water heater has two heat exchangers. The primary and secondary heat exchangers 
alternate roles , extending the life of the water heater  (see p. 4) . 
 
• The principle behind the water heater is simple: 
  
						

							 - 4 - 
TWO COMBUSTION SECTIONS WITHIN THE 910 (T-M50)  
 
The  water heater  contains two combustion sections .  The section  that turns on first is whichever 
section  the water heater  decides is the prim ary section.  The moment at which the secondary 
section  fires will depend on the total flow rate and set temperature of the water heater:   
Flow rate at which the secondary section fires  
( GPM ) 
Set temperature of the 910 (T-M50) 
(°F) 
3.2 100-120 
2.9 125,130 
2.6 140 
2.4 145,150 
2.1 155-185 
Example:  If the set temperature is 120ºF:  
＊The section(s) in operation is indicated by the black square(s).  
 
 
Right combustion section 
＊The primary and secondary section will reverse roles every 100 firing cycles or every 12 hours of unit operation. 
Left combustion section 
or 910 (T-M50) 910 (T-M50) 910 (T-M50) 910 (T-M50) 
Depending on which side is the primary section 
Total Flow < 0.5 GPM 
(no section turns on) 
 0.5 GPM ≦ Total Flow < 3.2 
GPM 
(primary section fires only) 
 3.2 GPM < Total Flow 
(both primary and 
secondary sections fire)  
						

							 - 5 - 
SAFETY GUIDELINES 
 
• Installation and service must be performed by a qualified installer (for 
example, a licensed plumber or gas fitter), otherwise the warranty by the 
manufacturer  will be void.
 
• The installer (licensed professional) is responsible for t he correct 
installation  of the  water  heater and for compliance with all n ational, 
state/provincial ,  and l ocal codes.
 
PLEASE READ THIS MANUAL CAREFULLY AND FOLLOW ALL DIRECTIO NS. 
 
GENERAL  
1.  Follow all local codes, or in the absence of loc al codes, follow the current edition of the 
National Fuel Gas  Code: ANSI Z223.1/NFPA 54 in  the USA  or  B149.1  Natural Gas , 
Propane  Installation Code in Canada.   
2.   Properly ground the unit in accordance with all local codes or in the absence of local codes, 
with the National Electrical Codes :  ANSI/NFPA 70 in the USA  or  CSA standard C22.1 
Canada Electrical Code Part 1 in Canada . 
3.   Carefully plan where  you intend to install the w ater heater. Please ensu re: 
•   Your water heater will have enough combustible air and 
proper ventilation.  
•   Locate your heater where water leakage will not damage 
surrounding areas (please refer to p. 6 ).  
4.   Check the rating plate for the correct  GAS TYPE, GAS 
PRESSURE, WATER PRESSURE  and ELECTRIC RATING.  
*If this unit does not match your requirements,  do not install and 
consult with  the manufacturer . 
5.   If any problem should occur, turn off all hot water taps and turn off 
the gas. Then call a trained technician or  the Gas Company or th e 
manufacturer.  
                                                                                 WARNING 
• Water temperatures over 125  ºF ( 52  ºC)  can cause severe burns instantly or death from 
scalding. The water temperature is set at 12 0 ºF ( 50 ºC)  from t he factory to minimize 
any scalding risk.  Before bathing or showering always check the water temperature.  
• Do not store or use gasoline or other flammables, vapors, or liquids in the 
vicinity of this  appliance.  
• Do not reverse the water and/or gas connecti ons as this will damage 
the gas valves and can cause severe injury or death . Follow the 
diagram  on p. 19 when installing your water heater:  
• Do not use this appliance if any part has been  in contact  with  or been 
immersed  in water. Immediately call a licens ed plumber, a licensed gas 
fitter, or a professional service technician to inspect and/or service the 
unit if necessary.  
• Do not disconnect the electrical supply if the ambient temperature will drop below 
freezing. The Freeze Prevention System only works if  the unit has electrical power. The 
warranty will not be covered if the heat exchanger is damaged due to freezing. Refer to 
the section on the Freeze Prevention System on p. 32  for more information. 
WARNING 
Prohibited 
Rating plate  
						

							 - 6 - 
INSTALLATION 
All gas water heaters require careful and correct installation to ensure safe and efficient 
operation. This manual must be followed exactly. Read the “Safety Guidelines” section at the 
beginning of this manual. 
 
• The warranty will not cover damage caused by water quality.  Water 
hardness  that leads to scale formation and/or corrosion  may 
affect/damage the water heater.  Hard water scaling and/or corrosion must 
be avoided or controlled by proper water treatment.  
• The  manufacturer  recommends  us ing the  d irect -vent   kit, when the 
water  heater  is installed  in a beauty salon.  Some chemicals used  in a 
beauty  salon  may affect  the flame sens or. 
Water heater may not work 
properly. 
• Although this water heater  is designed to operate with minimal sound,  the 
manufacturer  does not recommend installing the unit on a wal l 
adjacent to a bedroom, or a room that is intended for quiet study or 
meditation, etc. 
• Locate your heater close to a drain where water leakage will not do damage 
to surrounding areas.  As with any water heating appliance, the potential for 
leakage at some time in the life of the product does exist.  The manufacturer  
will not be responsible for any water damage that may occur.  If you install a 
drain pan under the unit, ensure that it will not restrict the combustion air 
flow.  
• The  water heater  weigh s 102  lbs.   Ensure that any and all support 
structures (whether it is installed on a wall, on a support stand, etc.) 
have enough strength to support and hold the  water heater.  
• When handling the water heater, do not place your hands inside the 
flue collar.  Injury may result . 
• The manufacturer does not recommend installing unit  in  an  attic due to 
safety issues.   If you install your water heater in  an attic:
 
• Make sure your unit will have enough combustion air  and proper 
ventilation. 
• Keep the area around your  water heater clean. When dust collects on the 
flame sensor, the water heater will shut down on errors.
 
•  If t he above conditions cannot be met, use the d irect-vent conversion kit 
9007669005 (TM -DV50) .
 
• Locat e unit for easy access for service  and maintenance. 
• A d rain pan  is required to be  installed under the  water heater in case of 
leaks.
 
WARNING 
NOTICE  
  
						

							- 7  - 
G ENERAL  
 
1. The  manifold gas pressure  is preset at the factory.   It is computer controlled and should 
not need adjustment.  
 
2.  Maintain proper space for servicing.  Install the unit so that it can be connected or 
removed easily.   Refer to p. 9 and p. 10  for proper clearances.
 
 
3.  The electrical connection requires a means  of disconnection, to terminate power to the 
wa ter heater for servicing and safety purposes.
 
 
4.  If  you will be installing the unit in a  contaminated area with a high level of dust, sand, 
flour, aerosols  or other contaminants/chemicals, they can become airborne and  enter 
and build up within the fan and burner causing damage to the unit. In those 
environments  (e.g. residential or commercial laundry facilities, hair salons, pet salons, 
chemical plants etc.), pleas e purchase the optional direct -vent  conversion kit and 
convert the  water heater to a sealed combustion unit .  Direct venting allows the water 
heater  to draw fresh intake air from the outside.  The warranty will not cover damage 
caused to the unit due to installation in a contaminated environment that has not been 
converted using the  direct-vent  conver sion kit . 
 
5.  Particles from flour, aerosols, and other contaminants may clog the air vent or reduce 
the  functions of the rotating fan and cause  improper burning of the gas. Regularly ensure 
that the area around the unit is dust -  or debris -free; regular maint enance is 
recommended for these types of environment.
 
 
6.  Do not install the unit where the exhaust vent is pointing into any opening in a building or 
where the noise may disturb your neighbors. Make sure the vent termination meets  the 
required  distance  by local code from  any doorway or opening to prevent exhaust from 
entering  a building (refer to p.  15).
 
 
 
 
INCLUDED  ACCESSORIES 
 
Check that  these items below are included with the water heater . 
 
 
Items  
 
Manual  
 
 
 
 
Communication Cable  
 
 
 
 
Qty: 1 
Qty: 1  
						

							 
- 8  - 
WARNING FOR INS TALLATIONS 
FOR YOUR SAFETY, READ BEFORE INSTALLATION:  
Do not install the heater where water, debris 
or flammable vapors may get into the flue 
terminal. This may cause damage to the 
heater and void the warranty. 
 
 
Do not have the vent terminal pointing t oward 
any opening into a building. Do not locate 
your heater in a pit or location where gas and 
water can accumulate. 
 
 
 
 
Do not install this water heater under an 
overhang less than 3 feet from its top or 
eaves. The area under an overhang must be 
open to three sides.  
 Do not install the water heater vent terminator 
within 1 ft. in the USA 
of any air intake or 
building opening,  and within 3 f t. in Canada of 
any air intake or building opening.  (Refer to 
p .1 5)
 
 
Do not install next to a dryer or any sou rce of 
airborne debris that can be trapped inside the 
combustion chamber, unless the system is 
direct vented.    
Prohibited Prohibited 
3  Ft .
 
 
 
Takagi
1  Ft.（ USA）3  Ft.（ Canada）
1  Ft.（ USA）3  Ft.（ Canada）1  Ft.（ USA）3  Ft.（ Canada） 
						

							 
- 9  - 
The dark square is the direction 
the dipswitch should be set to.  
Keep the clearances. 
OUTDOOR INSTALLATION 
 
1.  Follow all local codes, or in the absence of loc al codes, follow the current edition of the 
National Fuel Gas Code: ANSI Z223.1/NFPA 54 in  the USA  or  B149.1  Natural Gas , 
Propane  Installation Code in Canada.   
2.  Install outdoors only in areas with mild, temperate  climates. 
3.  Ensure that the unit is set for outdoor installation.  Locate the  central  computer board .  
On the cent ral computer board, locate the lower  bank of dipswitches to the right  of the 
7-S eg.  LED on the computer board.  The ‘OUT’ dipswitch on that bank  should be 
switched to its ‘ON’ (up) position (Do not adjust the  upper ban k of dipswitch es). 
 
 
 
 
 
   
 
 
 
 
 
 
 
 
 
 
 
 
  4. The outdoor vent cap must be used when unit is installed outdoor.  The manufacturer 
requires the use of its pa rt No. 9007677005 (TM-VC50) . 
5.  When installed outdoors, the  water heater  shall be wall -mounted or mounted on a stand.   
Locate the water heater in an open, unroofed area and maintain the following minimum 
cle arances:  
 
 
 
 
 
 
 
 
 
 
Make sure power to the unit is 
turned OFF before changing 
the dipswitch settings.  
TMP1
 
TMP2
 
TMP3
 
MODE
 
DIRE
 
OUT
 
P-ALARM
 
MST
 
O N 
1     2     3     4     5     6     7     8 
Lower Bank of Dipswitches 
There is a 3” clearance from the 
left and right sides of the unit to 
combustible and non-combustible 
surfaces.   However, if any portion 
or area of the surface is exposed to 
the exhaust fumes (i.e. directly to 
the  sides of the vent cap), that 
surface must be at least 24” 
away.    
 
 Back 0.5”  
 
Side 3” 
Side 3” 
Top 36” 
Bottom 12” 
*Side 24” *Side 24” 
    
Front 24” 
*Front 24” 
7-Seg LED 
Lower bank of 
dip switch es  
Upper bank of 
d ip switch es   
						

							 - 10 - 
Keep the clearances. 
INDOOR INSTALLATION 
 
1. Follow all local codes, or in the absence of 
loc al codes, follow the most recent edition 
of the National Fuel Gas Code: ANSI 
Z223.1/NFP A 54 in the USA  or  B149.1 
Natural Gas , Propane  Installation Code in 
Canada.   
 
2.  When installed indoors, the  water heater 
shall be located in an area to maintain the 
following minimum clearances around the 
unit:  
 
 
 
 
 
 
 
Combustion Air Supply   
The water heater  location must provide enough air for proper combustion and ventilation of the 
surrounding area. See the latest edition of ANSI Standard Z223.1 or any  applicable local codes. 
In general , these requirements specify that if the unit is installed in a confined space, there must 
be a permanent air supply opening.  
Minimum recommended air supply opening size for water heater:  
Water heater size 
 
When drawing make-up air from 
outside the building 
When drawing make -up air from inside 
the building (from other rooms within) 
MAX 
 380,000 BTU
/h 
25.3 Sq. IN 380 Sq. IN 
When combustion air is  supplied 
from  outside the building,  an 
opening 
communicating directly 
with the outside should have a 
minimum free area of one 
square inch per 15,000 BTUH 
input of the total input rating of 
water heater  in the enclosed 
area. 
When combustion air is supplied from 
inside the building, an opening 
communicating with the rest of the 
dwelling should have a minimum free 
area of one square inch per 1,000 
BTUH input of the total input rating of  
water heater  
in the enclosed area. 
This opening should never be less 
than 199 sq. in.  
 
Combusti ble Air Suppl ied by Mechanical fan or Make up air device  
 
The water heater is equipped with a combustible air sensor that will shut off the unit when 
inadequat e combustible air supply to unit is detected.  
•   If a  mechanical  fan or make up air device  is used to supply air to the water heater or 
utility room, the installer should make sure it does not create drafts which could cause 
nuisance shutdowns.   
•   If a blower i s necessary to provide adequate combustion air to the water heater, the 
blower and water heater must be set up so that the water heater cannot fire unless the 
blower is operating.  Possible methods include the use  of the  water heater  internal fan 
control port or the use  of external flow sensors/transmitters and relays.  
Top 12” 
Side 3” 
Side 3” 
Front 4” 
(24” Recommended 
for Maintenance)  Bottom 12” 
Back 0.5”