American Water Heater 30 Gallon UltraLow NOx Natural Gas Water Heater GU6130T30 User Manual

							1
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 electrical switch;  
    do not use any phone in your    
  building.
  •  Immediately call your gas supplier  
    from a neighbor’s phone. Follow  
    the gas supplier’s instructions.
  •  If you cannot reach your gas 
    supplier, call the fire department.
Installation and service must be performed 
by a qualified installer, service agency or 
the gas supplier.
WARNING:  If the information in these
instructions is not followed exactly, a fire 
or explosion may result causing property 
damage, personal injury or death.
INSTALLER:
•  AFFIX THESE INSTRUCTIONS TO OR ADJACENT   
TO THE WATER HEATER.
OWNER:
•  RETAIN THESE INSTRUCTIONS AND WARRANTY 
FOR FUTURE REFERENCE. RETAIN THE ORIGINAL 
RECEIPT AS PROOF OF PURCHASE.Table of Contents   ......................................................    2
Ultra Low Nox 
Gas Water Heater
with the Flame Guard™
Safety System
To obtain technical, warranty, or service assistance during or after 
the installation of this water heater, visit our website at:
http://www.americanwaterheater.com
or call toll free
1-800-999-9515
When calling for assistance, please have the following 
information ready:
1. Model number
2.  7 digit product number
3. Serial number
4.  Date of installation
5.  Place of purchase
Installation
Instructions and
Use & Care Guide
LOW LEAD
CONTENT
100263712
February 2015 
						

							2
Table Of Contents
Water Heater Safety .............................................................................. 1-2
Installing Your Gas Water Heater ........................................................ 3-16
  Unpacking the Water Heater ........................................................... 3
 Location Requirements ................................................................ 4-5
 Gas Supply .................................................................................. 6-7
  Combustion Air Supply and Ventilation ...................................... 7-11
  Water System Piping ............................................................... 12-13
  Temperature & Pressure Relief Valve ........................................... 14
 Special Applications ...................................................................... 14
 Installation Checklist ..................................................................... 16
Operating Your Water Heater ............................................................ 17-22
 Lighting Instructions ................................................................. 17-18
  Operating the Temperature Control System ................................. 21 
Operational Conditions ............................................................ 21-22
Maintenance of Your Water Heater ................................................... 23-28
Troubleshooting Charts ..................................................................... 28-31
Repair Parts Illustration ..................................................................... 32-33
PAGE
Your safety and the safety of others are very important.
We have provided many important safety messages in this manual and on your appliance. Always read and obey all 
safety messages.
This is the safety alert symbol.
This symbol alerts you to potential hazards that can kill or hurt you and others.
All safety messages will follow the safety alert symbol and either the word “DANGER” or
“WARNING.” These words mean:
Indicates an imminently hazardous situation which, if 
not avoided, will result in death or injury.
Indicates a hazardous situation which, if not avoided, 
could result in death or serious injury.
All safety messages will tell you what the potential hazard is, tell you how to reduce the chance of injury, and tell you 
what can happen if the instructions are not followed.
Important Instructions
•  Do not use this appliance if any part has been under water. Immediately call a qualified person. Water heaters sub-
jected to flood conditions or any time the gas controls, main burner or pilot have been submerged in water require 
replacement of the entire water heater.
•  Hydrogen gas can be produced in a hot water system that has not been used for a long period of time (generally 
two weeks or more). Hydrogen gas is extremely flammable and can ignite when exposed to a spark or flame. To 
prevent the possibility of injury under these conditions, we recommend the hot water faucet be opened for several 
minutes at the kitchen sink before using any electrical appliance which is connected to the hot water system. If 
hydrogen is present, there will probably be an unusual sound such as air escaping through the faucet as water 
begins to flow. Do not smoke or have any open flame near the faucet at the time it is open.
The California Safe Drinking Water and Toxic Enforcement Act requires the Governor of California to publish a list of 
substances known to the State of California to cause cancer, birth defects, or other reproductive harm, and requires 
businesses to warn of potential exposure to such substances.
•  WARNING:  This product contains a chemical known to the State of California to cause cancer, birth defects, or 
other reproductive harm. 
•  This appliance can cause low-level exposure to some of the substances listed in the Act.
This product is certified to comply with a maximum weighted average of 0.25% lead content as required in some areas.
WATER HEATER SAFETY 
						

							3
INSTALLING YOUR GAS WATER HEATER
Important Information About 
This Water Heater
This gas water heater was manufactured to voluntary 
safety standards to reduce the likelihood of a flammable 
vapor ignition incident. New technology used in meeting 
these standards makes this product more sensitive to  
installation errors or improper installation environments.  
Please review the Installation Checklist found at the end of 
the installation instructions section and make any required 
installation upgrades or changes.
Consumer Information
This water heater is design-certified by CSA International 
as a Category I, non-direct vented water heater which takes 
its combustion air either from the installation area or from 
air ducted to the unit from the outside.
This water heater must be installed according to all local 
and state codes or, in the absence of local and state codes, 
the “National Fuel Gas Code”, ANSI Z223.1(NFPA 54)-
current edition. This is available from the following:
CSA  America, Inc.
8501 East Pleasant Valley Road
Cleveland, OH 44131
National Fire Protection Association
1 Batterymarch Park
Quincy, MA 02269
Check your phone listings for the local authorities having 
jurisdiction over your installation.
Consumer Responsibilities
This manual has been prepared to acquaint you with the 
installation, operation, and maintenance of your gas water 
heater and provide important safety information in these 
areas. 
Read all of the instructions thoroughly before attempting 
the installation or operation of this water heater. 
Do not discard this manual. You or future users of this 
water heater will need it for future reference.
Service to the Flame Guard™ Safety System should only 
be performed by a qualified person.
Examples of a qualified person include: licensed plumbers, 
authorized gas company personnel, and authorized 
service personnel.
IMPORTANT: The manufacturer and seller of this water 
heater will not be liable for any damages, injuries, or 
deaths caused by failure to comply with the installation and 
operating instructions outlined in this manual. 
If you lack the necessary skills required to properly install 
this water heater, or you have difficulty following the 
instructions, you should not proceed but have a qualified 
person perform the installation of this water heater. 
Massachusetts code requires this water heater to be installed in accordance with Massachusetts Plumbing and 
Fuel Gas Code 248 CMR Section 2.00 and 5.00. 
A data plate identifying your water heater can be found next 
to the gas control valve/thermostat. When referring to your 
water heater, always have the information listed on the data 
plate readily available. 
Retain your original receipt as proof of purchase.
Unpacking the Water Heater
WARNING
Excessive Weight Hazard
Use two or more people to move and install 
water heater.
Failure to do so can result in back or 
other injury.
IMPORTANT: Do not remove any permanent instructions, 
labels, or the data label from either the outside of the water 
heater or on the inside of water heater panels.
•  Remove exterior packaging and place installation com-
ponents aside.
•  Inspect all parts for damage prior to installation and 
start-up.
•  Completely read all instructions before attempting to 
assemble and install this product.
•  After installation, dispose of/recycle all packaging 
materials. 
						

							4
Location Requirements
The Flame Guard™ Safety System is designed to reduce 
the risk of flammable vapor-related fires. The patented 
system protects your family by trapping the burning vapors 
within the water heater combustion chamber through 
the special flame-trap. The burning vapors literally “burn 
themselves out” without escaping back into the room. In the 
event of a flammable vapor incident, the Flame Guard™ 
Safety System disables the water heater by shutting off 
the gas supply to the water heater’s burner and pilot, 
preventing re-ignition of any remaining flammable vapors 
in the area. This will not prevent a possible fire/explosion 
if the igniter is depressed and flammable vapors have 
accumulated in the combustion chamber with the pilot 
light off. If you suspect a flammable vapor incident has 
occurred, do not use this appliance. Do not attempt to light 
this appliance, or depress the igniter button if you suspect 
flammable vapors have accumulated inside or outside the 
appliance. Immediately call a qualified person to inspect 
the appliance. Water heaters subjected to a flammable 
vapors incident will show a discoloration on the flame-trap 
FIRE AND EXPLOSION HAZARD
Can result in serious injury or death
        Do not store or use gasoline or other 
flammable vapors and liquids in the 
vicinity of this or any other appliance. 
Storage of or use of gasoline or other 
flammable vapors or liquids in the vicinity 
of this or any other appliance can result in 
serious injury or death.
Fl ammable VaporsFLAMMABLES
Read and follow water heater warnings and 
instructions.
WARNING
Carbon Monoxide Poisoning Hazard
Do not install in a mobile home.
Doing so can result in death or 
carbon monoxide poisoning.
WARNING
and require replacement of the entire water heater.  Note: 
Not following these instructions and/or an inadequate air 
supply can cause the Flame Guard™ Safety System to 
disable the water heater. Please make required installation 
and venting/air supply changes prior to resetting the system 
(see “Combustion Air Supply and Ventilation” section). 
Do not use or store flammable products such as gasoline, 
solvents, or adhesives in the same room or area near the 
water heater. If such flammables must be used, all gas 
burning appliances in the vicinity must be shut off and their 
pilot lights extinguished. Open the doors and windows for 
ventilation while flammable substances are in use. 
If flammable liquids or vapors have spilled or leaked in the 
area of the water heater, leave the area immediately and 
call the fire department from a neighbor’s home. Do not 
attempt to clean the spill until all ignition sources have been 
extinguished.
Keep combustibles such as boxes, magazines, clothes, 
etc. away from the water heater area.
Site Location
•  Select a location near the center of the water piping 
system. The water heater must be installed indoors and 
in a vertical position on a level surface. Do not install in 
bathrooms, bedrooms, or any occupied room normally 
kept closed.
•  Locate the water heater as close to the chimney or gas 
vent as practical. Consider the vent system piping and 
combustion air supply requirements when selecting the 
water heater location. The venting system must be able 
to run from the water heater to termination with minimal 
length and elbows. 
•  Locate the water heater near the existing gas piping. 
If installing a new gas line, locate the water heater to 
minimize the pipe length and elbows. 
NOTE:  This water heater must be installed according to all 
local and state codes or, in the absence of local and state 
codes, the “National Fuel Gas Code”, ANSI Z223.1(NFPA 
54)-current edition. 
						

							5
IMPORTANT: The water heater should be located 
in an area where leakage of the tank or connections 
will not result in damage to the area adjacent to the 
water heater or to lower floors of the structure. Due 
to the normal corrosive action of the water, the tank 
will eventually leak after an extended period of time. 
Also any external plumbing leak, including those from 
improper installation, may cause early failure of the tank 
due to corrosion if not repaired.  If the homeowner is 
uncomfortable with making the repair a qualified person 
should be contacted.  A suitable metal drain pan should 
be installed under the water heater as shown below, 
to help protect the property from damage which may 
occur from condensate formation or leaks in the piping 
connections or tank. The pan must limit the water level 
to a maximum depth of 1-3/4” and be two inches wider 
than the heater and piped to an adequate drain. 
NOTE: The pan must not restrict combustion air flow. 
Locate the water heater near an adequate indoor drain. 
The discharge pipe must terminate a maximum of six 
inches above a floor drain or external to the building.  In 
cold climates, it is recommended that the discharge pipe 
be terminated at an adequate drain inside the building. 
Outside drains are subject to freezing temperatures 
which can obstruct the drain line. The piping should be 
at least 3/4” ID and pitched for proper drainage. Under 
no circumstances will the manufacturer or seller of this 
water heater be held liable for any water damage which 
is caused by your failure to follow these instructions.
•  The water heater should be located in an area not 
subject to freezing temperatures. Water heaters located 
in unconditioned spaces (i.e., attics, basements, 
etc.) may require insulation of the water piping and 
drain piping to protect against freezing. The drain and 
controls must be easily accessible for operation and 
service. Maintain proper clearances as specified on the 
data plate.
•  Do not locate the water heater near an air-moving 
device. The operation of air-moving devices such as 
exhaust fans, ventilation systems, clothes dryers, 
fireplaces, etc., can affect the proper operation of 
the water heater. Special attention must be given to 
conditions these devices may create. Flow reversal of 
flue gases may cause an increase of carbon monoxide 
inside of the dwelling.
•  If the water heater is located in an area that is 
subjected to lint, dirt, and oil, it may be necessary 
to periodically clean the flame-trap (see “External 
Inspection & Cleaning of the Flame-trap” section).
Reverse flow 
of gasesExhaust
Fan
Figure 1A
Air-moving
Devices
Back
Sides
Sides
Top
ViewTop
to
ceiling
Vent
Front
24” minimum 
for service
Figure 2
Minimum Clearance
Locations
Clearances and Accessibility
NOTE: Minimum clearances from combustible surfaces are 
stated on the data plate adjacent to the gas control valve/
thermostat of the water heater.
The water heater is certified for installation on a 
combustible floor.
• IMPORTANT: If installing over carpeting, the carpeting 
must be protected by a metal or wood panel beneath 
the water heater. The protective panel must extend 
beyond the full width and depth of the water heater by 
at least three inches (76.2mm) in any direction; or if in 
an alcove or closet installation, the entire floor must be 
covered by the panel. 
• Figure 2 may be used as a reference guide to locate 
the specific clearance locations. A minimum of 24 
inches of front clearance should be provided for 
inspection and service.
State of California
NOTE: For California installation, this water heater must be 
braced, anchored, or strapped to avoid falling or moving
during an earthquake. Correct installation procedure in-
structions may be obtained from California’s Office of the 
State Architect, 1102 Q street, Suite 5100, Sacramento, CA 
95811. Instructions can also be downloaded to your com-
puter at www.dsa.dgs.ca.gov/Pubs.
  METAL
DRAIN
PAN
AT LEAST 2” GREATER  THAN THE 
DIAMETER OF THE WATER HEATER.PIPED TO AN 
ADEQUATE DRAIN
6” MAXIMUM
AIR GAP  DISCHARGE PIPE
(DO NOT CAP OR PLUG) 
Figure 1
Drain Pan Installation 
						

							6
Gas Supply
Gas Requirements
IMPORTANT: Read the data plate to be sure the water 
heater is made for the type of gas you will be using in 
your home. This information will be found on the data 
plate located near the gas control valve/thermostat. If the 
information does not agree with the type of gas available, 
do not install or light. Call your dealer.
NOTE: An odorant is added by the gas supplier to the gas 
used by this water heater. This odorant may fade over an 
extended period of time. Do not depend upon this odorant 
as an indication of leaking gas.
Gas Piping
The gas piping must be installed according to all local and state 
codes or, in the absence of local and state codes, the “National 
Fuel Gas Code”, ANSI Z223.1(NFPA 54)-current edition.
Table 1 on page 7 provides a sizing reference for commonly 
used gas pipe materials. Consult the “National Fuel Gas Code” 
for the recommended gas pipe size of other materials.
Refer to Figure 3
NOTE:  When installing gas piping, apply approved pipe joint 
compound.
1.  Install a readily accessible manual shut-off valve in the 
gas supply line as recommended by the local utility. 
Know the location of this valve and how to turn off the 
gas to this unit.
2.  Install a sediment trap (if not already incorporated 
as part of the water heater) as shown. The sediment 
trap must be no less than three inches long for the 
accumulation of dirt, foreign material, and water 
droplets.
3.  Install a ground joint union between the gas control 
valve/thermostat and the manual shut-off valve. This 
is to allow easy removal of the gas control valve/ 
thermostat.
4.  Turn the gas supply on and check for leaks. Test all 
connections by brushing on an approved noncorrosive 
leak-detection solution. Bubbles will show a leak. 
Correct any leak found.
Manual Gas
Shut-off Valve
Ground
Joint
Union
Sediment Trap
3” Minimum
Check with local
utility for
minimum height Figure 3
Gas Piping
Gas Pressure
IMPORTANT: The gas supply pressure must not exceed the 
maximum supply pressure as stated on the water heater’s data 
plate. The minimum supply pressure is for the purpose of input 
adjustment.
Gas Pressure Testing
IMPORTANT: This water heater and its gas connection must 
be leak tested before placing the appliance in operation.
•  If the code requires the gas lines to be tested at a pressure 
exceeding 14” W.C., the water heater and its manual shut-
off valve must be disconnected from the gas supply piping 
system and the line capped.
•  If the gas lines are to be tested at a pressure less than 
14” W.C., the water heater must be isolated from the gas 
supply piping system by closing its manual shut-off valve.
U.L. recognized fuel gas and carbon monoxide (CO) detectors 
are recommended in all applications and should be installed 
using the manufacturer’s instructions and local codes, rules, or 
regulations.
NOTE: Air may be present in the gas lines and could prevent 
the pilot from lighting on initial start-up. The gas lines should 
be purged of air by a qualified person after installation of the 
gas piping system. While purging the gas piping system of air, 
make sure that the fuel is not spilled in the area of the water 
heater installation, or any source of ignition. If the fuel is spilled 
while purging the piping system of air follow the “WHAT TO DO 
IF YOU SMELL GAS” instructions on the cover of this manual.
Explosion Hazard
Use a new CSA approved gas supply line.
Install a shut-off valve.
 
  Failure to follow these instructions can 
result in death, explosion, or 
carbon monoxide poisoning.
WARNING
Do not connect a natural gas water heater to
an L.P. gas supply.
Do not connect an L.P. gas water heater to
a natural gas supply. 
						

							7
Combustion Air Supply and 
Ventilation
IMPORTANT:  Air for combustion and ventilation must 
not come from a corrosive atmosphere. Any failure due 
to corrosive elements in the atmosphere is excluded from 
warranty coverage.
The following types of installation (not limited to the 
following) will require outdoor air for combustion due to 
chemical exposure and may reduce but not eliminate the 
presence of corrosive chemicals in the air:
• beauty shops
•  photo processing labs
•  buildings with indoor pools 
•  water heaters installed in laundry, hobby, or craft rooms
•  water heaters installed near chemical storage areasCombustion air must be free of acid-forming chemicals 
such as sulfur, fluorine, and chlorine. These elements are 
found in aerosol sprays, detergents, bleaches, cleaning 
solvents, air fresheners, paint, and varnish removers, 
refrigerants, and many other commercial and household 
products. When burned, vapors from these products form 
highly corrosive acid compounds. These products should 
not be stored or used near the water heater or air inlet.
Combustion and ventilation air requirements are 
determined by the location of the water heater. The water 
heater may be located in either an open (unconfined) area 
or in a confined area or small enclosure such as a closet or 
small room. Confined spaces are areas with less than 50 
cubic feet for each 1,000 BTU/HR of the total input for all 
gas-using appliances.
Carbon Monoxide Hazard
Water heater must be vented to outdoors.
Vent must be installed by a qualified person 
using the installation instructions.
Examples of a qualified person include:   
gas technicians, 
authorized gas company personnel, 
and authorized service persons.
Failure to follow these instructions can result 
in death or carbon monoxide poisoning.
WARNING 
						

							8
Unconfined Space
A water heater in an unconfined space uses indoor air for 
combustion and requires at least 50 cubic feet for each 
1,000 BTU/HR of the total input for all gas appliances. The 
table below shows a few examples of the minimum square 
footage (area) required for various BTU/HR inputs.
IMPORTANT:
•  The area must be open and be able to provide the 
proper air requirements to the water heater. Areas that 
are being used for storage or contain large objects may 
not be suitable for water heater installation. 
•  Water heaters installed in open spaces in buildings with 
unusually tight construction may still require outdoor 
air to function properly. In this situation, outside air 
openings should be sized the same as for a confined 
space. 
•  Modern home construction usually requires supplying 
outside air into the water heater area. 
Confined Space 
For the correct and proper operation of this water heater, 
ample air must be supplied for the combustion, ventilation, 
and dilution of flue gases. Small enclosures and confined 
areas must have two permanent openings so that sufficient 
fresh air can be drawn from outside of the enclosure. One 
opening shall be within 12 inches of the top and one within 
12 inches of the bottom of the enclosure as shown in 
Figure 4.
The size of each opening (free area) is determined by the 
total BTU/HR input of all gas utilization equipment (i.e., 
water heaters, furnaces, clothes dryers, etc.) and the 
method by which the air is provided. The BTU/HR input can 
be found on the water heater data plate. Additional air can 
be provided by two methods:
1.  All air from inside the building.
2.  All air from outdoors.
Figure 4
Opening Locations-
Confined Spaces12” maximum
Permanent 
openings to 
the outside or 
additional 
rooms within 
the buildingCloset
 or
other
confined
space
12” maximum
All Air from Inside the Building
When additional air is to be provided to the confined area 
from additional room(s) within the building, the total volume 
of the room(s) must be of sufficient size to properly provide 
the necessary amount of fresh air to the water heater 
and other gas utilization equipment in the area. If you are 
unsure that the structure meets this requirement, contact 
your local gas utility company or other qualified agency for 
a safety inspection. 
Each of the two openings shall have a minimum free area 
of 1 square inch per 1,000 BTU/HR of the total input rating 
of all gas utilization equipment in the confined area, but not 
less than 100 square inches (Figure 5).
30,000
45,000
60,000
75,000
90,000
105,000
120,000
135,000188
281
375
469
563
657
750
8449 x 21
14 x 20
15 x 25
15 x 31
20 x 28
20 x 33
25 x 30
28 x 30 Typical Room
with 8 Ceiling Minimum Square
Feet with 
8 Ceiling BTU/HR
Input
Table 2
Confined
Space
Figure 5 
All Air from Inside Building
Confined Space Installation
Permanent
Openings
1 square
inch/1000
BTU/HR
(minimum
100 sq. In.) 
						

							9
All Air from Outdoors
Outdoor fresh air can be provided to a confined area either 
directly or by the use of vertical and horizontal ducts. The 
fresh air can be taken from the outdoors or from crawl or 
attic spaces that freely communicate with the outdoors. 
Attic or crawl spaces cannot be closed and must be 
properly ventilated to the outside. 
Ductwork must be of the same cross-sectional area as 
the free area of the opening to which they connect. The 
minimum dimension of rectangular air ducts cannot be less 
than three inches. 
The size of each of the two openings is determined by the 
method in which the air is to be provided. Refer to Table 
3 to calculate the minimum free area for each opening. 
Figures 6, 7, and 8 are typical examples of each method. 
Louvers and Grilles
In calculating free area for ventilation and combustion 
air supply openings, consideration must be given to the 
blocking effect of protection louvers, grilles, and screens. 
These devices can reduce airflow, which in turn may 
require larger openings to achieve the required minimum 
free area. Screens must not be smaller than 1/4” mesh. If 
the free area through a particular design of louver or grille 
is known, it should be used in calculating the specified free 
area of the opening. If the design and free area are not 
known, it can be assumed that most wood louvers will allow 
20 - 25% of free area while metal louvers and grilles will 
allow 60 - 75% of free area. 
Louvers and grilles must be locked open or interconnected 
with the equipment so that they are opened automatically 
during equipment operation. 
Keep louvers and grilles clean and free of debris or other 
obstructions.
Table 3
Minimum Free Area of Permanent Openings for Ventilation and 
Combustion Air  Supply  - All Air  from  Outdoors  Only.
Based on the total BTU/HR input rating for all utilizing equip-
ment within the confined space.
Opening SourceMinimum Free Area 
Per Opening (sq. in.)Reference 
Drawing
* Direct to outdoors 1 sq. in, per 4000 BTU/HRFigure 6
Vertical ducts 1 sq. in, per 4000 BTU/HRFigure 7
Horizontal ducts 1 sq. in, per 2000 BTU/HRFigure 8A
Single Opening 1 sq. in, per 3000 BTU/HRFigure 8B
Example: A water heater with an input rate of 50,000 BTU/HR 
using horizontal ducts would require each opening to have a 
minimum free area of 25 square inches.
Minimum free area = 50,000 BTU/HR x 1 sq. in. / 2000 BTU/HR = 
25 Sq. Inches.
*  These openings connect directly with the outdoors 
through a ventilated attic, a ventilated crawl space, or 
through an outside wall.
Consult the local codes of your area for specific ventilation 
and combustion air requirements.
Confined
Space
Figure 8A
All Air from Outdoors
Using Horizontal Ducts
Outdoor
Air Ducts Outlet
Inlet
1 sq. inch
per
2000 BTU/HR
1 sq. inch per
4000 BTU/HR
Confined
Space
Figure 6
All Air from Outdoors; Inlet Air from Ventilated
Crawl Space/Outlet Air to Ventilated Attic
Inlet air
from the
crawl
space
Install above
insulation
Gable vent
to outdoors
Outlet
air to attic
1 Sq. inch per
4000 BTU/HR
Alternate
Air Inlet
Open
Foundation
Vent
Confined
Space
Figure 7
All Air from Outdoors
Through Ventilated Attic
Inlet air duct
1 sq. inch per
4000 BTU/HR
Install above
insulation
Gable vent
to outdoors
Outlet air
to attic
1 Sq. inch per
4000 BTU/HR 
12” maximum
1 sq. Inch
per
2000 BTU/HR 
						

							10
Vent Pipe System
This water heater uses a non-direct, single-pipe vent system 
to remove exhaust gases created by the burning of fossil fuels. 
Air for combustion is taken from the immediate water heater 
location or is ducted in from the outside (see “Combustion Air 
Supply and Ventilation” section).
This water heater must be properly vented for the removal of 
exhaust gases to the outside atmosphere. Correct installation 
of the vent pipe system is mandatory for the proper and 
efficient operation of this water heater and is an important 
factor in the life of the unit.
The vent pipe must be installed according to all local and state 
codes or, in the absence of local and state codes, the “National 
Fuel Gas Code”, ANSI Z223.1(NFPA 54)-current edition. The 
vent pipe installation must not be obstructed so as to prevent 
the removal of exhaust gases to the outside atmosphere.
IMPORTANT: The use of vent dampers is not recommended 
by the manufacturer of this water heater. Although some vent 
dampers are certified by CSA International, this certification 
applies to the vent damper device only and does not mean 
they are certified for use on this water heater.
U.L. recognized fuel gas and carbon monoxide (CO) detectors 
are recommended in all applications and should be installed 
using the manufacturer’s instructions and local codes, rules, or 
regulations.
IMPORTANT:  If you lack the necessary skills required to 
properly install this venting system, you should not proceed, 
but get help from a qualified person.
Draft Hood Installation
Align the legs of the draft hood with the slots provided. 
Insert the legs and secure the draft hood to the water 
heater’s top with the four screws provided as shown in 
Figure 9. Do not alter the draft hood in any way. If you are 
replacing an existing water heater, be sure to use the new 
draft hood supplied with the water heater. IMPORTANT: 
50K models must use the supplied 4” draft hood. See 
Figure 9.
Vent Pipe Size 
It is important that you follow the guidelines in these 
instructions for sizing a vent pipe system. If a transition to 
a larger vent size is required, the vent transition connection 
must be made at the draft hood outlet.
Vent Connectors
1.  Type B, Double wall, U.L. Listed Vent Pipe.
2.  Single wall Vent Pipe.
Maintain the manufacturer’s specified minimum clearance from 
combustible materials when using type B double wall vent 
pipe.
Vent connectors made of type B, double wall vent pipe 
material may pass through walls or partitions constructed 
of combustible material if the minimum listed clearance is 
maintained.
Maintain a six inch minimum clearance from all combustible 
materials when using single wall vent pipe.
IMPORTANT: Single wall vent pipe cannot be used for water 
heaters located in attics and may not pass through attic 
spaces, crawl spaces or any confined or inaccessible location. 
A single wall metal vent connector cannot pass through any 
interior wall.
When installing a vent connector, please note the following:
•  Install the vent connector avoiding unnecessary bends, 
which create resistance to the flow of vent gases.
•  Install without dips or sags with an upward slope of at least 
1/4-inch per foot.
•  Joints must be fastened by sheet metal screws or other 
approved means. It must be supported to maintain 
clearances and prevent separation of joints and damage.
•  The length of the vent connector cannot exceed 75% of 
the vertical vent height.
•  The vent connector must be accessible for cleaning, 
inspection, and replacement.
•  Vent connectors cannot pass through any ceiling, floor, 
firewall, or fire partition.
•  It is recommended (but not mandatory) that a minimum 12 
inches of vertical vent pipe be installed on the draft hood 
prior to any elbow in the vent system to improve conditions 
for positive flow of venting gases.
IMPORTANT: Existing vent systems must be inspected for 
obstructions, corrosion, and proper installation.
Figure 9
Draft hood Inst allation
Sheet Metal Screws (four provided)
Draft hood
Jacket top
Install the draft hood with
the four screws provided.
SlotSlot
Legs
Legs
Sheet Metal Screws (four provided)
Draft hood
Jacket top
Install the draft hood with
the four screws provided.
SlotSlot
Legs
Legs
4” Draft Hood
(50K Models) 3”- 4” Draft Hood
Combination
Alternative
Opening
Location
1 sq. Inch 
Per 3000 BTU/HR Confined
Space
Figure 8B
All Air from Outdoors 
Using a Single Permanent Opening