Giant UG40-92TFTT-N2U User manual

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.
• From a neighbor’s phone, immediately call your gas sup-
plier. 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.
HYBRID TANK-TANKLESS WATER HEATER
(AUTOMATIC CIRCULATING TANK)
OWNER’S MANUAL
INSTALLATION AND OPERATING INSTRUCTIONS
IMPORTANT
READ ALL OF THE INSTRUCTIONS THOROUGHLY BEFORE INSTALLING OR OPERATING THIS WATER HEATER.
THIS MANUAL PROVIDES INFORMATION ON THE INSTALLATION, OPERATION, AND MAINTENANCE OF THE
WATER HEATER. FOR PROPER OPERATION AND SAFETY IT IS IMPORTANT TO FOLLOW THE INSTRUCTIONS
AND ADHERE TO THE SAFETY PRECAUTIONS. A LICENSED PROFESSIONAL MUST INSTALL THE WATER
HEATER ACCORDING TO THE EXACT INSTRUCTIONS. THE CONSUMER MUST READ THE ENTIRE MANUAL
TO PROPERLY OPERATE THE WATER HEATER AND TO HAVE REGULAR MAINTENANCE PERFORMED.
54000052
© 2015 Giant Factories Inc. Printed in Canada GI-IM046En-0415
For your records, write the model and serial number here:
Model # _____________________________________________
Serial # _____________________________________________
R
R
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
If the information in these instructions is not followed exact-
ly, a fire or explosion may result causing property damage,
personal injury, or death.

2
Safety Information .................................2
Safety Behaviors ..................................3
Installation Instructions.............................5
Installer Qualifications ............................ 5
General Instructions .............................. 5
Determine Installation Location ..................... 6
Minimum Clearances ............................. 6
Installation Location .............................. 6
Typical Installation Illustration ...................... 7
Checklist to Determine Installation Location............ 8
Combustion Air Requirements ...................... 8
Venting Requirements ........................... 10
Checklist for Combustion Air and Venting Requirements . 12
Installation of Plumbing .......................... 12
Checklist for Plumbing ........................... 13
Installation of Gas Supply......................... 14
Massachusetts-Required Plumbing ................. 15
Connect Electricity .............................. 16
Adjust for High Altitude .......................... 16
Checklist for Gas and Electricity .................... 17
Final Checklist.................................. 17
Technical Data ...................................18
Specifications .................................. 18
Dimensions.................................... 19
Wiring Diagram................................. 20
Replacement Parts................................21
Operating Instructions .............................22
Consumer Operation Guidelines for the
Safe Operation of your Water Heater ................ 22
How to use the Temperature Controller .............. 23
Diagnostic Codes and Remedies.................... 24
System Maintenance ..............................26
Air Screen Inspection, Detection & Cleaning .......... 26
Water Filter Inspection, Detection & Cleaning.......... 26
Consumer Support ................................29
Warranty Registration Information .................. 29
Warranty ........................................30
TABLE OF CONTENTS
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your information shared with these businesses, please contact customer service and ask not to have your information shared. However, we
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SAFETY INFORMATION
Indicates a potentially hazardous situation which, if not avoided, could result in serious injury
or death.
Indicates an imminently hazardous situation which, if not avoided, will result in serious injury
or death.
Indicates a potentially hazardous situation which, if not avoided, could result in minor or mod-
erate injury. It may also be used to alert against unsafe practices.
This is the safety alert symbol. This symbol alerts you to potential hazards that can kill or hurt you and others.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Your safety and the safety of others is extremely important during the installation, operation, and servicing of this water heater. Many safety
related messages have been provided in this manual and on your water heater. Always read and obey all safety messages. These messages
will point out the potential hazard, tell you how to reduce the risk of injury, and tell you what will happen if the instructions are not followed.

32
SAFETY BEHAVIORS
California law requires this notice to be provided:
California Proposition 65 lists chemical substances known to the state to cause cancer, birth defects, death, serious illness or other re-
productive harm. This product may contain such substances, be their origin from fuel combustion (gas, oil) or components of the product
itself.
If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury, or death.
Hot water can be dangerous, especially for infants or children, seniors, or disabled people. There is hot
water scald potential if the thermostat is set too high.
Water temperatures over 125ºF (51ºC) can cause severe burns or scalding resulting in death.
Hot water can cause first degree burns with exposure for as little as:
Three (3) seconds at 140ºF (60ºC)
Twenty (20) seconds at 130ºF (54ºC)
Eight (8) minutes at 120ºF (48ºC)
Test the temperature of the water before placing a child in the bath or shower.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
•BURN HAZARD. Hot exhaust and vent may cause serious
burns. Keep away from water heater unit. Keep children and
animals away from unit.
•Hot water outlet pipes leaving the unit can be hot to touch. In
residential applications, insulation must be used for hot water
pipes below thirty-six (36) inches (91.4 cm) due to burn risk
to children.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
•Before operating, smell all around the appliance area for gas.
Be sure to smell next to the floor because some gas is heavier
than air and will settle on the floor.
•Keep the area around the appliance clear and free from com-
bustible materials, gasoline, and other flammable vapors and
liquids.
•Combustible construction refers to adjacent walls and ceiling
and should not be confused with combustible or flammable
products and materials.
•Combustible and/or flammable products and materials should
never be stored in the vicinity of this or any gas appliance.
•Always check the water temperature before entering a shower
or bath.
•To protect yourself from harm, before performing maintenance:
* Turn off the electrical power supply by unplugging the
power cord or by turning off the electricity at the circuit
breaker. (The temperature controller does not control
the electrical power.)
* Turn off the gas at the manual gas valve, usually located
adjacent to the water heater.
* Turn off the incoming water supply. This can be done
at the cold water supply valve immediately below the
water heater or by turning off the water supply to the
building.
•Use only your hand to push in or turn the gas control knob.
Never use tools. If the knob will not push in or turn by hand,
do not try to repair it; call a licensed professional. Force or at-
tempted repair may result in a fire or explosion.
•Do not use this appliance if any part has been under water.
Immediately call a licensed professional to inspect the appli-
ance and to replace any part of the control system and any gas
control which has been under water.
•Do not use substitute parts that are not authorized for this ap-
pliance.
•Should overheating occur or the gas supply fail to shut off, turn
off the manual gas control valve to the appliance.
•Do not adjust the DIP switch unless specifically instructed to
do so.
•Do not use an extension cord or an adapter plug with this ap-
pliance.
•Any alteration to the appliance or its controls can be dangerous
and will void the warranty.
•Make sure the water heater and its water lines are protected
from freezing. Damage due to freezing is not covered by the
warranty.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION

4
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
•Do not use this appliance if any part has been under water.
Immediately call a qualified service technician to inspect the
appliance and to replace any part of the control system and any
gas control which has been under water.
•Any alteration to the appliance or its controls can be dange-
rous and will void the warranty.
•This appliance is equipped with a three-prong plug for your
protection against shock hazard and should be plugged
directly into a properly grounded three-prong receptacle. Do
not cut or remove the ground prong from this plug.
FVIR (Flammable Vapor Ignition Resistant) Sensor
Flammable liquids such as cleaning solvents, aerosols, paint
thinners, adhesives, gasoline, and propane must be handled and
stored with extreme care. These flammable liquids emit flammable
vapors and when exposed to an ignition source can result in a
fire hazard or explosion. Flammable liquids should not be used or
stored in the vicinity of this or any other appliance.
This water heater is equipped with a flammable vapor sensor and
meets the requirements of ANSI Z21.10.1. If flammable vapors are
detected, the flammable vapor sensor will close the gas supply to
the water heater, the ignition source will be disabled and a “FE”
error code will flash on the controller. If the controller is flashing a
‘’FE’’ or if flammable vapors are suspected:
•Leave the area immediately, while leaving the exit point open to
allow ventilation
•Do not touch any electric device (including phone or light switch)
•Call emergency personnel from a neighbor’s phone
•Do not try to reset the water heater or light the pilot to any other
appliance. When safety personnel has identified the area as safe
and all flammable vapors have been removed and eliminated
from the area, the units can be reset by unplugging the unit then
plugging back in.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Do not spray or use chemicals containing bleach, cleaners,
polish, silicone, phosphorous, or lubricants near the water
heater. These chemicals will damage the flammable vapor sen-
sor. Never clean or tamper with the flammable vapor sensor. Do
not place cat litter near the appliance as it can corrode or damage
the sensor. If the sensor is corroded or damaged, its reaction
time can be affected and it may not react as described.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Carbon Monoxide Hazard
•Install vent system per local and national codes.
•Read and follow all instructions in this section.
• DO NOT install this water heater above 5,400 ft (1,646 m).
•
DO NOT obstruct water heater air intake.
•
DO NOT operate water heater if flood damaged.
•Failure to properly vent this appliance can result in property
damage, personal injury, or death.
•Every home should have a carbon monoxide (CO) alarm in the
hallway near bedrooms in each sleeping area. Check batteries
monthly and replace them annually.
SAFETY BEHAVIORS INSTALLATION INSTRUCTIONS

54
Installer Qualifications
A licensed professional must install the appliance, inspect it, and
leak test it before use. The warranty will be voided in case of im-
proper installation.
The installer should have skills such as:
•Gas sizing
•Connecting gas lines, water lines, valves, and electricity
•Knowledge of applicable national, state, and local codes
•Installing venting through a wall or roof
•Venting Category I, Fan Assist Appliances per NFPA54 and local
codes
If you lack these skills, contact a licensed professional.
General Instructions
DO NOT
•Do not install the UG40-92TFTT-N2U or UG40-92TFTT-P2U out-
doors.
•Do not install the appliance in an area where water leakage of
the unit or connections will result in damage to the area adjacent
to the appliance or to lower floors of the structure. When such
locations cannot be avoided, it is recommended that a suitable
drain pan, adequately drained, be installed under the appliance.
The pan must not restrict combustion air flow.
•Do not obstruct the flow of combustion and ventilation air.
•Do not use this appliance in an application such as a pool or
spa heater that uses chemically treated water. (This appliance
is suitable for filling large or whirlpool spa tubs with potable
water.)
•Do not use substitute parts that are not authorized for this ap-
pliance.
MUST DO
•The installation must conform with local codes or, in the absence
of local codes, with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54, or the Natural Gas and Propane Installation Code, CSA
B149.1.
•When installed, the appliance must be electrically grounded in
accordance with local codes or, in the absence of local codes,
with the National Electrical Code, ANSI/NFPA 70, or the Canadian
Electrical Code, CSA C22.1.
•The appliance and its main gas valve must be disconnect-
ed from the gas supply piping system during any pressure
testing of that system at test pressures in excess of 1/2 psi
(3.5 kPa) (13.84 in W.C.).
•The appliance must be isolated from the gas supply piping sys-
tem by closing its individual manual shutoff valve during any
pressure testing of the gas supply piping system at test pres-
sures equal to or less than 1/2 psi (3.5 kPa) (13.84 in W.C.).
•Make sure the water heater and its water lines are protected from
freezing. Damage due to freezing is not covered by the warranty.
•You must follow the installation instructions and those in Care
and Maintenance for adequate combustion air intake and ex-
haust.
•Install the vacuum relief valve per local codes.
•Massachusetts 248 CMR Section 10.14 (I) “All potable water
pressure tanks shall be provided with a vacuum-relief valve at
the top of the tank that will operate up to a maximum water
pressure of 200 P.S.I.G. and to a maximum water temperature
of 200ºF (93.3ºC).”
Figure 1 Vacuum-Relief Valve
If required, install per local code and
valve manufacturer instructions
(Not Supplied)
INFORMATION
If a water heater is installed in a closed water supply system, such
as one with a backflow preventer in the cold water supply line,
means shall be provided to control thermal expansion. Contact
the water supplier or local plumbing inspector on how to control
thermal expansion.
•Should overheating occur or the gas supply fail to shut off, turn
off the manual gas control valve to the appliance.
•Keep the air intake location free of chemicals such as chlo-
rine or bleach that produce fumes. These fumes can dam-
age components and reduce the life of your appliance.
Table 1
Prepare for installation
Parts included
• Water heater
• Temperature-Pressure
• Relief (T&P) Valve
• Gas Valve
Tools needed
• Manometer
• Pipe wrenches (2)
• Adjustable pliers
• Screwdrivers (2)
• Wire cutters
• Gloves
• Safety glasses
• Level
Tools that might be needed
• Saw
• Threading machine with
heads and oiler
• Torch set
• Copper tubing cutter
• Steel pipe cutter
Materials needed
• Soap solution
• Approved venting • Teflon tape (recommended) or pipe compound
Materials that may be needed
• Heat tape
• Pipe insulation
• Electrical wire and conduit
per local code
• Single gang electrical box
• Wire nuts
• Unions and drain valves
INSTALLATION INSTRUCTIONS

6
Determine Installation Location
You must ensure that clearances will be met and that the vent
length will be within required limits. Consider the installation en-
vironment, water quality, and need for freeze protection. Require-
ments for the gas line, water lines, and electrical connection can be
found in their respective installation sections of this manual.
Water Quality
Water heater care should include evaluation of water quality. Water
that contains chemicals exceeding the levels below affect and
damage the heat exchanger. Replacement of the heat exchang-
er due to water quality damage is not covered by the warranty.
Table 2
Maximum Level
Total Hardness Up to 200 mg / L
Aluminium * Up to 0.2 mg / L
Chlorides * Up to 250 mg / L
Copper * Up to 1.0 mg / L
Iron * Up to 0.3 mg / L
Manganese * Up to 0.05 mg / L
pH * 6.5 to 8.5
TDS (Total Dissolved Solids) * Up to 500 mg / L
Zinc * Up to 5 mg / L
* Source: Part 143 National Secondary Drinking Water Regulations
If you install this water heater in an area that is known to have hard
water or that causes scale buildup, the water must be treated and/
or the heat exchanger flushed regularly.
Environment
Air surrounding the water heater is used for combustion and must
be free of any compounds that cause corrosion of internal com-
ponents. These include corrosive compounds that are found in
aerosol sprays, detergents, bleaches, cleaning solvents, oil based
paints/varnishes, and refrigerants. The air in beauty shops, dry
cleaning stores, photo processing labs, and storage areas for pool
supplies is often filled with these compounds. Therefore it is rec-
ommended that such locations be avoided.
If it is necessary for a water heater to be located in areas which
may contain corrosive compounds, the following instructions are
strongly recommended.
IMPORTANT CONSIDERATIONS FOR INSTALLATION:
• DO NOT install in areas where air for combustion can be con-
taminated with chemicals.
•Before installation, consider where air has the ability to travel
within the building to the water heater.
•Chemicals that are corrosive in nature should not be stored or
used near the water heater.
Damage and repair due to corrosive compounds in the air is not
covered by warranty.
Minimum Clearances
The minimum clearances from both combustibles and non-com-
bustibles construction is: 0 inch from the sides, 0 inch from the
back, twelve (12) inches (30.5 cm) from the top, four (4) inches
(10.2 cm) from the front.
0” Min 0” Min
0” Min
4''
(10.2 cm)
Min
12'' (30.5 cm) Min
Figure 2
Installation Location
This water heater is not approved for use in manufactured (mobile)
homes or outdoor installations.
Attic
The water heater installation must be performed in such a way that
if the tank or any connection should leak, the flow of water will not
cause damage to the structure. For this reason, it is not advisable
to install the water heater in an attic or upper floor. When such lo-
cations cannot be avoided, a suitable drain pan should be installed
under the water heater. (See drain pan at the following page)
Garage
Although this water heater is equipped with a flammable vapor
sensor, gasoline, and other flammable substances should not be
stored or used in the same vicinity or area of the water heater or
any other appliance that may produce a spark or open flame.
It is not required to position this water heater on a stand as this
water heater complies with the FVIR requirements and the burn-
er and igniter are positioned greater than eighteen (18) inches
(45.7 cm) from the base of the unit.
This water heater must be positioned or located as to not be sub-
ject to damage by a moving vehicle.
Refer to local code for installation requirements in a garage.
Crawl Space
When installing this water heater in a crawl space, position the
water heater on a solid concrete platform or base to avoid damage
to the unit. (Do not use wood)
Drain Pan
If the water heater is installed in a location that could damage
the home or structure precautions must be taken to protect the
property from water damage. In the event of a tank or component
failure, an appropriately sized pan must be installed under the wa-
ter heater. The pan must drain with a minimum diameter of ¾”
(1.9 cm) connection and shall be drained per local code require-
ments.
Stand
Depending on local code, a stand may not be required due to the
ignition source being over eighteen (18) inches (45.7 cm) from the
base of the appliance.
Alcove or closet
See clearance requirements and combustion air requirements.
INSTALLATION INSTRUCTIONSINSTALLATION INSTRUCTIONS

76
16
1
13
15 14 12 11
2
3
4
5
7
8
9
10
6
11161819 17
11161819 17
16
1
13
15 14 12 11
2
3
4
5
7
8
9
10
6
ALIMENTATION
EN EAU FROIDE
SORTIE D’EAU
CHAUDE
ALIMENTATION
EN EAU FROIDE
ALIMENTATION
NON-TEMPÉRÉE
ALIMENTATION
RETOUR
COLD WATER
SUPPLY
HOT WATER
OUTLET
COLD WATER
SUPPLY
NON-TEMPERED
SUPPLY
SUPPLY
RETURN
MIXING VALVE INSTALLATION
Typical Installation Illustration
I.D. Description
1 4” (10.2 cm) B-Vent
2 Combustion Air Screen
3 Outlet Receptacle
4 Operation Unit / Temperature Control
5Temperature & Pressure-Relief Valve
Discharge Pipe
6 Drain Pan
7 Drip Leg (Sediment Trap)
8 Gas Union
9 Gas Control Valve
10 Thermal Expansion Tank
11 Cold Water Supply
12 Cold Water Supply Valve
13 Temperature & Pressure-Relief Valve
14 Cold and Hot Unions
15 Hot Water Outlet Valve
16 Hot Water Outlet
17 Non-Tempered Return Line
18 Thermostatic Mixing Valve
19 Non-Tempered Supply Line
INSTALLATION INSTRUCTIONS

8
Insulation Blanket
This water heater meets or exceeds the National Appliance Energy
Conservation Act standards with respect to insulation and standby
losses. If an insulation blanket is still desired, the following proce-
dure must be followed.
a) Maintain an adequate distance from the vent.
b) Do not cover the front door of the tankless engine or the lower
enclosure of the assembly.
c) Do not cover the combustion air grill located on the front door
of the tankless engine.
d) Do not obstruct the operation of the pressure-relief valve.
e) Obtain new warning labels from the manufacturer to place on
the blanket, directly over the existing labels.
f) Frequently inspect the blanket to ensure the insulation blanket
has not been disturbed.
Checklist to Determine Installation Location
□The water heater is not exposed to corrosive compounds in
the air.
□The water heater location complies with the clearances stated
in the manual and on the label, located on the side of the unit.
□The area surrounding the water heater does not contain flam-
mable vapors that could ignite.
□The water supply does not contain chemicals or exceed total
hardness that will damage the heat exchanger.
□The water heater and its water lines are protected from freezing.
□A standard 3-prong 120 VAC, 60 Hz properly grounded wall
outlet or other properly grounded 120 VAC, 60 Hz source is
available.
□The installation must conform with local codes or, in the ab-
sence of local codes, with the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, or the Natural Gas and Propane Installation
Code, CSA B149.1.
□Leave the entire manual taped to the water heater or give the
entire manual directly to the consumer.
Combustion Air Requirements
This water heater requires adequate combustion air for ventilation
and dilution of flue gases. Failure to provide adequate combustion
air can result in unit failure, fire, explosion, serious bodily injury, or
death. Use the following methods to ensure adequate combustion
air is available for correct and safe operation of this water heater.
Combustion air must be free of corrosive chemicals. Do not
provide combustion air from corrosive environments. Appli-
ance failure due to corrosive air is not covered by warranty.
IMPORTANT
Combustion air must be free of acid-forming chemicals, such as
sulfur, fluorine, and chlorine. These chemicals have been found to
cause rapid damage and decay and can become toxic when used
as combustion air in gas appliances. Such chemicals can be found
in, but not limited to, bleach, ammonia, cat litter, aerosol sprays,
cleaning solvents, varnish, paint, and air fresheners. Do not store
theseproducts orsimilar productsinthe vicinityof thiswater heater.
Unconfined Space
An unconfined space is defined in National Fuel Gas Code, ANSI
Z223.1/NFPA 54 as “a space whose volume is not less than fif-
ty (50) cubic feet per 1,000 BTU/hr (4.8 m3per kW per hour) of
the aggregate input rating of all appliances installed in that space.
Rooms communicating directly with the space in which the appli-
ances are installed, through openings not furnished with doors,
are considered a part of the unconfined space.” If the “unconfined
space” containing the appliance(s) is in a building with tight con-
struction, additional outside air may be required for proper op-
eration. Outside air openings should be sized the same as for a
confined space.
Figure 3
Note: plafond de
8 pi (2,4m)
Note: plafond de
8 pi (2,4m)
35 pi (10,6m)
35 pi
(10,6m)
25 pi (7,6m)
25 pi
(7,6m)
Note: 8 FT (2.4 m)
ceiling Note: 8 FT (2.4 m) ceiling
35 FT (10.6 m)
35 FT
(10.6 m)
25 FT (7.6 m)
25 FT
(7.6 m)
Unconfined Space
91,300 BTU Water Heater and
a 100,000 BTU Furnace
Confined Space
Confined Space
(Small Room, Closet, Alcove, Utility Room, Etc.)
A confined space is defined in the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 as “a space whose volume is less than fifty (50)
cubic feet per 1,000 BTU/hr (4.8 m3per kW per hour) of the ag-
gregate input rating of all appliances installed in that space.” A
confined space must have two combustion air openings. Size the
combustion air openings based on the BTU input for all gas utiliza-
tion equipment in the space and the method by which combustion
air is supplied:
Louvers and Grilles
When sizing the permanent opening as illustrated in Figure 5 ,
consideration must be taken for the design of the louvers or
grilles to maintain the required free area required for all gas utiliz-
ing equipment in the space. If the free area of the louver or grille
design is not available, assume wood louvers will have 25% free
area and metal louvers or grilles will have 75% free area. Under no
circumstance should the louver, grille, or screen have openings
smaller than ¼” (6 mm).
Example:
Wood: 10 in. (25 cm) x 12 in. (30.5 cm) x 0.25 = 30 in2(193.5 cm2)
Metal: 10 in. (25 cm) x 12 in (30.5 cm) x 0.75 = 90 in2(580.6 cm2)
Location
To maintain proper circulation of combustion air, two permanent
openings (one upper, one lower) must be positioned in confined
spaces. The upper shall be within twelve (12) inches (30.5 cm) of
the confined space and the lower opening shall be within twelve
(12) inches (30.5 cm) of the bottom of the confined space. Open-
ings must be positioned as to never be obstructed.
INSTALLATION INSTRUCTIONSINSTALLATION INSTRUCTIONS

98
Combustion air provided to the appliance should not be taken
from any area of the structure that may produce a negative pres-
sure (i.e. exhaust fans, powered ventilation fans).
Figure 4
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
OUVERTURES
PERMANENTES
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
DE SORTIE
D’AIR
CONDUIT
D’ENTRÉE
D’AIR
CHAUFFE-
EAU
SORTIE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
D’ENTRÉE
D’AIR
[Arrive à 1 pi
(30,5cm)
au-dessus
du sol]
CHAUFFE-
EAU
SORTIE
D’AIR
ENTRÉE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
BOUCHES D’AÉRATION POUR
VIDE SANITAIRE NON-CHAUFFÉ
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
PERMANENT
OPENINGS
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
OUTLET
AIR DUCT
INLET
AIR DUCT
WATER
HEATER
OUTLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
INLET
AIR DUCT
[Ends 1Ft
(30.5cm)
above floor]
WATER
HEATER
OUTLET
AIR
INLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS FOR
UNHEATED CRAWL SPACE
Figure 5
12” (30,5 cm) MAX
12” (30,5 cm) MAX
OUVERTURES
PERMANENTES
10''
(25 cm)
12” (30,5 cm)
12 in. (30.5 cm) MAX
12 in. (30.5 cm) MAX
PERMANENT
OPENINGS
10''
(25 cm)
12” (30.5 cm)
Using Indoor Air For Combustion
When using air from other room(s) in the building, the total vo-lume
of the room(s) must be of adequate volume (Greater than fifty (50)
cubic feet per 1,000 BTU/hr). Each combustion air opening must
have at least one (1) square inch (6.45 cm2) of free area for each
1,000 BTU/hr, but not less than one hundred (100) square inches
(645 cm2) each.
Using Outdoor Air For Combustion
Outdoor air can be provided to a confined space through two
permanent openings, one commencing within twelve (12) inches
(30.5 cm) of the top and one commencing within twelve (12) inches
(30.5 cm) of the bottom of the confined space.
The openings shall communicate to the outside by one of two
ways:
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
OUVERTURES
PERMANENTES
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
DE SORTIE
D’AIR
CONDUIT
D’ENTRÉE
D’AIR
CHAUFFE-
EAU
SORTIE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
D’ENTRÉE
D’AIR
[Arrive à 1 pi
(30,5cm)
au-dessus
du sol]
CHAUFFE-
EAU
SORTIE
D’AIR
ENTRÉE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
BOUCHES D’AÉRATION POUR
VIDE SANITAIRE NON-CHAUFFÉ
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
PERMANENT
OPENINGS
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
OUTLET
AIR DUCT
INLET
AIR DUCT
WATER
HEATER
OUTLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
INLET
AIR DUCT
[Ends 1Ft
(30.5cm)
above floor]
WATER
HEATER
OUTLET
AIR
INLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS FOR
UNHEATED CRAWL SPACE
DIRECTLY THROUGH HORIZONTAL DUCTS
Figure 6
INDIRECTLY THROUGH VERTICAL DUCTS
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
OUVERTURES
PERMANENTES
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
DE SORTIE
D’AIR
CONDUIT
D’ENTRÉE
D’AIR
CHAUFFE-
EAU
SORTIE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
D’ENTRÉE
D’AIR
[Arrive à 1 pi
(30,5cm)
au-dessus
du sol]
CHAUFFE-
EAU
SORTIE
D’AIR
ENTRÉE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
BOUCHES D’AÉRATION POUR
VIDE SANITAIRE NON-CHAUFFÉ
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
PERMANENT
OPENINGS
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
OUTLET
AIR DUCT
INLET
AIR DUCT
WATER
HEATER
OUTLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
INLET
AIR DUCT
[Ends 1Ft
(30.5cm)
above floor]
WATER
HEATER
OUTLET
AIR
INLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS FOR
UNHEATED CRAWL SPACE
Figure 7
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
OUVERTURES
PERMANENTES
CHAUFFE-
EAU
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
DE SORTIE
D’AIR
CONDUIT
D’ENTRÉE
D’AIR
CHAUFFE-
EAU
SORTIE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
CONDUIT
D’ENTRÉE
D’AIR
[Arrive à 1 pi
(30,5cm)
au-dessus
du sol]
CHAUFFE-
EAU
SORTIE
D’AIR
ENTRÉE
D’AIR
FOURNAISE
CHEMINÉE OU
ÉVENT À GAZ
BOUCHES D’AÉRATION POUR
VIDE SANITAIRE NON-CHAUFFÉ
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
PERMANENT
OPENINGS
WATER
HEATER
FURNACE
CHIMNEY OR
GAS VENT
OUTLET
AIR DUCT
INLET
AIR DUCT
WATER
HEATER
OUTLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
INLET
AIR DUCT
[Ends 1Ft
(30.5cm)
above floor]
WATER
HEATER
OUTLET
AIR
INLET
AIR
FURNACE
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS FOR
UNHEATED CRAWL SPACE
Figure 8
INSTALLATION INSTRUCTIONS

10
When communicating directly with the outdoors through
horizontal ducts, each opening shall have a minimum free area
of one (1) in2/2,000 BTU/hr (11.0 cm2/kW) of total input rating of
all appliances in the confined space. Note: If ducts are used, the
cross sectional area of the duct must be greater than or equal
to the required free area of the openings to which they are con-
nected.
When communicating indirectly with the outdoors through
vertical ducts, each opening shall have a minimum free area of
one (1) in2/4,000 BTU/hr (5.5 cm2/kW) of total input rating of all
appliances in the confined space. Combustion air to the appli-
ance can be provided from a well ventilated attic or crawl space.
Venting Requirements
Venting
This water heater must be vented vertically to the outside of the
building or structure.
This water heater is not designed or certified for side wall horizon-
tal vent terminations.
All installations must be vented in accordance with National Fuel
Gas Code, ANSI Z223.1/NFPA 54 - latest edition and the require-
ments of state or local codes. In Canada, the furnaces must be
vented in accordance with the National Standard of Canada, CAN/
CSA B149.1 and CAN/CSA B149.2 - latest editions and amend-
ments and the codes of the local utility or other authority having
jurisdiction.
NOTE: The vertical height of the Category I venting system must
be at least as great as the horizontal length of the venting system.
•All vent (Category I) passing through a concealed space, an attic,
or floor MUST be Type B double wall vent and/or Type B double
wall vent connectors. For vent passing through an interior wall,
use Type B vent with ventilated thimble ONLY .
•The UG40-92TFTT-N2U or UG40-92TFTT-P2U CANNOT be ven-
ted into any chimney serving an open fireplace or any other solid
fuel burning appliance.
•Use the same diameter Category I connector or vent as permit-
ted by NFPA 54/ANSI Z223.1 venting tables.
•It is not permitted to reduce vent diameter (4” or 10.2 cm).
•It is emphasized that vertical Category I vent or vent connector
runs be as short and direct as possible.
•Vertical outdoor runs of type B or ANY single wall vent below the
roof line are NOT permitted.
•All horizontal vent runs to be sloped up away from the UG40-
92TFTT-N2U or UG40-92TFTT-P2U a minimum of ¼” (6 mm)
per foot.
•All horizontal vent runs are to be supported, at a minimum, every
6’ (1.8 m) using suitable clamps and/or metal straps.
•Existing gas vent or chimney must be checked to ensure they
meet clearances and local codes.
The UG40-92TFTT-N2U or UG40-92TFTT-P2U can ONLY be con-
nected to a manufactured chimney or vent that complies with a
recognized standard. Venting into a masonry or concrete chim-
ney is only permitted as outlined in the NFPA 54/ANSI Z223.1
National Fuel Gas Code venting tables. It is therefore a contractu-
al obligation on the part of the installer to follow all safe venting
requirements.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Poison carbon monoxide gas hazard
If this appliance is replacing a previously common vented
water heater, it may be necessary to resize the existing chim-
ney liner or vent to prevent over sizing problems for the other
remaining appliance(s). See codes and/or standard having ju-
risdiction. Failure to properly vent this water heating appliance
or other appliance(s) can result in property damage, personal
injury, or death.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
TO PREVENT POSSIBLE PERSONAL INJURY OR DEATH DUE
TO ASPHYXIATION, COMMON VENTING WITH OTHER MANU-
FACTURER’S INDUCED DRAFT APPLIANCES IS NOT ALLOWED.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Devices attached to the vent system intended to increase system
efficiency by reducing the heat loss of the vent system MUST
not be used on this water heater. Giant accepts no liability for
damage or injury if such devices are installed on the vent system
with this appliance.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Vent Pipe Assembly: To avoid damage to the vent and vent
adapter, pre-drill holes with a 1/8” (3.1 mm) drill bit. Attach the
vent to the vent adapter with #8 screws.
TUYAU D’ÉVACUATION
(4” OU 10,2 cm
DE DIAMÈTRE)
VIS
VIS
VIS
VENT PIPE
(4” OR 10.2 cm
DIAMETER)
SCREW
SCREW
SCREW
Figure 9
INSTALLATION INSTRUCTIONS

1110
INSTALLATION INSTRUCTIONS
Vent Dampers
Vent dampers must be certified in accordance with ANSI Z21.68.
Before installing any flue damper, consult the local gas authority
and damper manufacturer for proper installation.
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Thermal Operated Vent Dampers SHOULD NOT be used with
this appliance. This appliance has a thermal efficiency greater
than 80%. This higher efficiency will result in lower flue gas
temperatures. Such temperatures may be too low to activate a
thermal operated vent damper. Use of a thermal operated flue
damper on this product may result in spillage of exhaust gases
and ultimately carbon monoxide poisoning.
Vent Inspection
The entire vent system (Combustion air ducts, louvers, and ex-
haust vent) must be checked periodically for signs of obstruction
or damage. If damaged components are observed, they must be
repaired or replaced immediately.
Vent Size
This water heater is equipped with a four (4) inch (10.2 cm) vent
adapter and must never be attached to a vent smaller than four (4)
inches (10.2 cm). Certain applications may require vent diame-
ters greater than four (4) inches (10.2 cm). Consult your local gas
supplier or authority to aid in the proper vent diameter selection
per the requirements of the vent tables in the current edition of the
National Fuel Gas Code ANSI Z223.1/NFPA 54.
Vent Connectors
Vent Connectors are relatively short runs of vent connecting the
appliance to the chimney or vertical vent run.
Following is a list of appropriate vent connector material to use
between the water heater and the chimney:
•Type B (B-Vent) Double wall, U.L. listed vent pipe
•Type B (B-Vent) Single wall, U.L. listed vent pipe
Note the following when installing a vent connector from the appli-
ance to the chimney or vertical vent:
CHEMINÉE OU
ÉVENT HOMOLOGUÉ
RACCORD
D’ÉVENT
PENTE D’AU MOINS
1/4” PAR PIED
CHIMNEY OR
VENT CONNECTOR
MIN. 1/4 in. RISE
PER FOOT
Figure 10
Length:
A vent connector shall be as short as practical and the appli-
ance located as close as practical to the chimney or vent. The
maximum horizontal length of the vent connector cannot ex-
ceed 75% of the height of the chimney or vent. Unnecessary
bends should be avoided as to not create excessive resistance
to flow of vent gases.
Prohibited locations
Vent Connectors cannot pass through any ceiling, floor, fire-
wall, or fire partition.
Single-wall vent connectors
A single-wall vent connector must not pass through any interior
walls, floors, or ceilings. A single-wall vent connector must not
be installed in attics, crawl spaces, or any other confined space
or inaccessible location. Maintain a minimum of six (6) inches
(15.2 cm) from combustibles when using single walled vent
connectors.
Double Walled, B-Vent
It is acceptable to pass through walls or partitions with double
walled, B Vent.
Slope
Vent connectors must pitch ¼ inch per foot (2.1 cm per me-
ter) upward.
Inspection
The entire length of the vent connector shall be readily acces-
sible for inspection, cleaning, and replacement.
Joints
Must be fastened by sheet metal screws or other approved
methods.
Support
Vent connectors must be supported per the vent manufactu-
rer’s installation instructions to avoid dips or sags in the vent
and maintain the required clearances.
Vent Termination
All flue (Vent) gases must be directed to the outdoors of the build-
ing or structure and must not terminate horizontally.
Table 3
Roof Slope H (minimum)
ft m
Flat to 6/12 1.0 0.30
Over 6/12 to 7/12 1.25 0.38
Over 7/12 to 8/12 1.5 0.46
Over 8/12 to 9/12 2.0 0.61
Over 9/12 to 10/12 2.5 0.76
Over 10/12 to 11/12 3.25 0.99
Over 11/12 to 12/12 4.0 1.22
Over 12/12 to 14/12 5.0 1.52
Over 14/12 to 16/12 6.0 1.83
Over 16/12 to 18/12 7.0 2.13
Over 18/12 to 20/12 7.5 2.28
Over 20/12 to 21/12 8.0 2.44

12
Figure 11
ÉVENT À GAZ
HOMOLOGUÉ
ORIFICE DE DÉCHARGE INFÉRIEUR
H (MINIMUM) -
HAUTEUR MINIMUM
DU TOIT VERS LA
DÉCHARGE INFÉRIEURE
PENTE DU TOIT
EST x/12
12
x
12
x
LISTED CAP
LOWEST DISCHARGE OPENING
H (MINIMUM) -
MINIMUM HEIGHT
ROOF PITCH IS
x/12
The vent termination shall comply with the following requirements:
•If the gas vent is twelve (12) inches (30.5 cm) or less in diameter
and located not less than eight (8) feet (2.4 m) from a vertical
wall or similar obstruction, the termination must comply with
the requirements stated in Table 3 and Figure 2 . If the gas
vent is greater than twelve (12) inches (30.5 cm) in diameter or
located less than eight (8) feet (2.4 m) from a vertical wall or
similar obstruction, the termination must end not less than two
(2) feet (61 cm) above any portion of a building within ten (10)
feet (3 m) horizontally.
•B-Vent type gas vent shall terminate at least five (5) feet (1.5 m)
in vertical height above the highest connected appliance draft
hood or flue collar.
•Decorative shrouds or coverings shall not be installed over the
gas vent termination unless listed for use with the specific gas
vent and are installed in accordance with the manufacturer’s
installation instructions.
•All gas vents shall extend through the roof flashing, roof jack,
or roof thimble and terminate with a listed cap or listed roof
assembly.
•The gas vent shall terminate at least three (3) feet (91.4 cm)
above any forced air inlet located within ten (10) feet (3 m).
Masonry Vertical Venting
Masonry Chimneys shall be built and installed in accordance with
NFPA 211, Standard for Chimneys, fireplaces, Vents and Solid
Fuel-Burning Appliances.
Before assembling the vent connector to a chimney, the chimney
must be inspected for signs of obstruction or damage. If previous-
ly used for solid or liquid fuel burning appliances or fireplaces, the
chimney must be cleaned.
Do not connect the vent of this water heater to a chimney servicing
a separate solid fuel burning appliance.
Do not connect the vent of this water heater to a tile lined masonry
chimney. The chimney must be lined with either B-Vent or a listed
chimney lining system.
Connection to a chimney must be firmly attached, sealed, and
must be located above the extreme bottom of the chimney.
B-Vent Vertical Venting
Vertical gas vent must be installed with U.L. listed type B-vent ma-
terial in accordance with the manufacturer’s installation instruc-
tions and the requirements stated in the “ National Fuel Gas Code”,
NFPA 54, ANSI Z223.1 - latest edition and the requirements of local
codes.
Vent should extend in a generally vertical direction. Any vent angle
less than 45 degrees is considered horizontal. The total horizontal
distance of the vent system plus the horizontal length of the vent
connector must not exceed 75 % of the vertical height of the vent.
An unused chimney or masonry enclosure may be used as a chase
for the installation of listed B-vent material.
Common Venting
As a Category I appliance, this water heater can be vented vertical-
ly with type B-1 vent systems and lined masonry chimneys. Follow
the National Fuel Gas Code, ANSI Z223.1 and or the National Gas
Installation code, CSA-B149.1 & .2 for proper installation practices.
If you are unsure or need assistance in correct application of a
common vent installation, consult the local gas authority for assis-
tance in the vent system design.
Checklist for Combustion Air and Venting Requirements
□Verify proper clearances around the vents.
□Ensure that the Combustion Air Requirements are followed that
will provide sufficient combustion air for the appliance.
□Ensure you have used the correct venting products for Catego-
ry 1 and that you have completely followed the venting man-
ufacturer’s installation instructions and these installation in-
structions. All installations must be vented in accordance with
National Fuel Gas Code NFPA 54/ANSI Z223.1 - latest edition
and the requirements of state or local codes. In Canada, the
furnaces must be vented in accordance with the National Stan-
dard of Canada, CAN/CSA B149.1 and CAN/CSA B149.2 - latest
editions and amendments and the codes of the local utility or
other authority having jurisdiction.
□All horizontal vent runs must be sloped up away from the water
heater a minimum of 1/4” (6 mm) per foot.
□Verify that the vent termination clearances are followed.
□Verify that there is adequate combustion air.
Installation of Plumbing
Temperature & Pressure-Relief Valve
Install the Temperature & Pressure-Relief (T&P) Valve according
to these instructions.
This water heater is provided with a properly certified Temperature
& Pressure-Relief Valve by the manufacturer.
An approved Temperature & Pressure-Relief Valve is required by
the American National Standard (ANSI Z21.10.3) for all water hea-
ting systems, and shall be accessible for servicing.
INSTALLATION INSTRUCTIONS

1312
DO NOT
•Do not plug the T&P valve and do not install any reducing fit-
tings or other restrictions in the relief line. The relief line should
allow for complete drainage of the T&P valve and the line.
•Do not place any other type valve or shut-off device between the
relief valve and the water heater.
MUST DO
•The T&P valve must comply with the standard for Relief Valves
and Automatic Gas Shutoff Devices for Hot Water Supply Sys-
tems ANSI Z21.22 and/or the standard Temperature, Pressure,
Temperature and Pressure-Relief Valves and Vacuum-Relief
Valves, CAN1-4.4.
•The T&P valve must be rated up to 150 psi and at least the max-
imum BTU/hr of the appliance.
•The discharge from the T&P Valve should be piped to the ground
or into a drain system to prevent exposure or possible burn
hazards. Follow local codes. Water discharged from the relief
valve could cause severe burns instantly, scalds, or death.
•The Temperature & Pressure-Relief Valve must be manually
operated once a year to check for correct operation.
•The T&P valve should be added to the hot water outlet line
and near the hot water outlet according to the manufacturer’s
instructions. DO NOT place any other type valve or shut-off device
between the relief valve and the water heater.
INFORMATION
•If a T&P discharges periodically, this 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 situ-
ation. Do not plug the relief valve.
Piping Requirements
A manual valve must be placed in the water inlet connection to the
water heater before it is connected to the water line. Unions may
be used on both the hot and cold water lines for future servicing
and disconnection of the unit.
DO NOT
•Do not introduce toxic chemicals such as those used for boiler
water treatment to the potable water used for space heating.
MUST DO
•The piping (including soldering materials) and components con-
nected to this appliance must be approved for use in potable
water systems.
•Purge the water line to remove all debris and air. Debris will
damage the water heater.
•If the appliance will be used as a potable water source, it must
not be connected to a system that was previously used with a no
potable water heating appliance.
•Ensure that the water filter on the water heater is clean and
installed.
Connect Water Heater to Water Supply
Water connections to the tankless water heater should follow all
state and local plumbing codes.
If this is a standard installation, refer to the Piping Diagram for
Basic Installation.
1) Use of this layout should provide a trouble-free installation
for the life of the water heater. Before making the plumbing
connections, locate the COLD water inlet and the HOT water
outlet. These fittings are both 3/4” N.P.T. male thread. Make
sure that the dip tube is installed in the cold water inlet. Install
a shut-off valve close to the water heater in the cold water line.
It is recommended that unions be installed in the cold and hot
water lines so that the water heater can be easily disconnected,
if servicing is required.
2) When assembling the hot and cold piping, use a good food
grade of pipe joint compound, and ensure all fittings are tight.
It is imperative that open flame is not applied to the inlet and
outlet fittings, as heat will damage or destroy the plastic lined
fittings. This will result in premature failure of the fittings,
which is not covered by the warranty.
Filling the Water Heater
DO NOT OPERATE THIS WATER HEATER UNLESS IT IS COM-
PLETELY FILLED WITH WATER. To prevent damage to the ap-
pliance, all air must be relieved from the system and a hot water
fixture must be flowing water before the water heater is plugged
in and turned on. To ensure safe and effective operation of the
waterheater use the following filling procedure:
To fill the water heater:
1) Ensure the drain valve located at the bottom of the tank is
closed.
2) Open nearest hot water fixture in the system.
3) Open the cold supply valve to the water heater.
4) Keep the hot water fixture open until the tank is filled and cons-
tant flow is obtained at the fixture.
5) Check water heater connections and plumbing system for da-
mage or leaks. Repair, if needed.
Checklist for Plumbing
□Purge the water line of all debris and air by closing the hot iso-
lation valve and opening the cold isolation valve and its drain.
Debris will damage the water heater. Use a bucket or hose, if
necessary.
□Ensure that hot and cold water lines are not crossed to the unit
and are leak free.
□Ensure that the temperature & pressure-relief valve is installed.
□Clean the inlet water filter. Refer to the “Water Filter Inspection,
Detection and Cleaning” section in this manual for the water
filter cleaning procedure.
□Check for proper water pressure to the water heater. Minimum
water pressure is 20 psi. A water pressure of 30-50 psi is
recommended for maximum performance.
INSTALLATION INSTRUCTIONS

14
Installation of Gas Supply
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
1) If you are not knowledgeable or qualified to install gas lines
or connections, then contact a licensed professional to
install the gas supply.
2) Turn off 120 V power supply.
3) Turn off the gas.
4) Gas is flammable. Do not smoke or provide other ignition
sources while working with gas.
5) Do not turn on the water heater or gas until all fumes are
gone.
General Instructions
In order to access the gas connections, remove the screws that
attach the lower enclosure to the assembly.
CONNEXION DE GAZ (1/2” (12,7 mm) MNPT)
GAS CONNECTION (1/2” (12.7 mm) MNPT)
Figure 12
MUST DO
•A manual gas control valve must be placed in the gas supply
line to the water heater. A union can be used on the connection
above the shut-off valve for the future servicing or disconnection
of the unit.
•Check the type of gas and the gas inlet pressure before connec-
ting the water heater. If the water heater is not of the gas type
that the building is supplied with, DO NOT connect the water
heater. Contact the dealer for the proper unit to match the gas
type.
•Check the gas supply pressure immediately upstream at a loca-
tion provided by the gas company. Supplied gas pressure must
be within the limits shown in the “Specifications” section with all
gas appliances operating.
•Before placing the appliance in operation all joints including the
heater must be checked for gas tightness by means of leak de-
tector solution, soap and water, or an equivalent nonflammable
solution, as applicable. (Since some leak test solutions, inclu-
ding soap and water, may cause corrosion or stress cracking,
the piping shall be rinsed with water after testing, unless it has
been determined that the leak test solution is noncorrosive.)
•Use approved connectors to connect the unit to the gas line.
Purge the gas line of any debris before connection to the water
heater.
•Any compound used on the threaded joint of the gas piping shall
be a type which resists the action of liquefied petroleum gas
(propane / LPG).
•The gas supply line shall be gas tight, sized, and so installed
as to provide a supply of gas sufficient to meet the maximum
demand of the heater and all other gas consuming appliances at
the location without loss of pressure.
•Always check all gas pipe connections and fittings for leaks be-
fore operating the water heater. Use soapy water on all fittings
and visually inspect for bubble formation. Rinse off soapy water
and wipe dry.
INFORMATION
•Refer to an approved pipe sizing chart if in doubt about the size
of the gas line.
Size the gas pipe
The gas supply must be capable of handling the entire gas load
at the location. Gas line sizing is based on gas type, the pressure
drop in the system, the gas pressure supplied, and gas line type.
For gas pipe sizing in the United States, refer to the National Fuel
Gas Code, NFPA 54. The below information is provided as an ex-
ample. The appropriate table from the applicable code must be
used.
1) For some tables, you will need to determine the cubic feet per
hour of gas required by dividing the gas input by the heating
value of the gas (available from the local gas company). The gas
input needs to include all gas products at the location and the
maximumBTUusageatfullloadwhenallgasproductsareinuse.
INSTALLATION INSTRUCTIONS

1514
INSTALLATION INSTRUCTIONS
Hot to
house Check
valve
Cold to water heater
Air handler
Circulation
Pump
Clapet
de retenue
Échangeur d'air
Eau chaude
vers la
maison Pompe
circulatrice
5Arrivée d'eau froide
Massachusetts - Required Plumbing
Figure 13

16
2) Use the table for your gas and pipe type to find the pipe size
required. The pipe size must be able to provide the required
cubic feet per hour of gas or the required BTU/hour.
Cubic Feet
per Hour =
Gas Input of all gas products (BTU/HR)
_________________________
Heating Value of Gas (BTU/FT3)
Example:
The heating value of natural gas for your location is 1,000 BTU/FT3.
The gas input of the UG40-92TFTT-N2U or UG40-92TFTT-P2U
is 91,500 BTU/HR. Additional appliances at the location require
65,000 BTU/HR. Therefore the cubic feet per hour = (91,500 +
65,000) / 1,000 = 156.5 FT3/HR (4.43 m3/HR). If the pipe length is
ten (10) feet (3 m) then the 3/4 inch (1.9 cm) pipe size is capable
of supplying 156.5 FT3/HR (4.43 m3/HR) of natural gas.
Table 4
Pipe Sizing Table - Natural Gas
Schedule 40 Metallic Pipe
Inlet Pressure: less than 2 psi (55 inches (140 cm) W.C.)
Pressure Drop: 0.3 inches (7.6 mm) W.C.
Specific Gravity: 0.60
Capacity in Thousands of BTU per Hour
Length Pipe Size (inches)
1/2 3/4 1 1 1/4
10
131 273 514 1,060
20
90 188 353 726
30
- 151 284 583
40
- 129 243 499
50
- 114 215 442
60
- 104 195 400
70
- 95 179 368
80
- 89 167 343
90
- 83 157 322
100
- 79 148 304
Table 5
Pipe Sizing Table - Propane Gas
Schedule 40 Metallic Pipe
Inlet Pressure: 11.0 inches (27.9 cm) W.C.
Pressure Drop: 0.5 inches (1.3 cm) W.C.
Specific Gravity: 1.50
Capacity in Thousands of BTU per Hour
Length Pipe Size (inches)
1/2 3/4 1 1 1/4
10
291 608 1,150 2,350
20
200 418 787 1,620
30
160 336 632 1,300
40
137 287 541 1,110
50
122 255 480 985
60
110 231 434 892
80
101 212 400 821
100
94 197 372 763
Connect Electricity
DANGER
WARNING
CAUTION
AVERTISSEMENT
ATTENTION
Do not use an extension cord or an adapter plug with this ap-
pliance.
The water heater must be electrically grounded in accordance
with local codes and ordinances or, in the absence of local
codes, in accordance with the National Electrical Code, ANSI/
NFPA No. 70.
Water heaters are equipped with a three-prong (grounding) plug
for your protection against shock hazard and should be plugged
directly into a properly grounded three-prong receptacle. Do not
cut or remove the grounding terminal from this plug.
Do not rely on the gas or water piping to ground the water heater.
A screw is provided in the junction box for the grounding connec-
tion.
The water heater requires 120 VAC, 60 Hz power from a properly
grounded circuit.
If using the five (5) foot (1.5 m) long power cord, plug it into a
standard 3-prong 120 VAC, 60 Hz properly grounded wall outlet.
Adjust for High Altitude
Set switches # 2 and # 3 to the values shown in table below for
your altitude. The default setting for the appliance is 0-2,000 ft
(0-610 m) with switches # 2 and # 3 in the OFF position.
Dip Switch Settings
Altitude No.2 No.3
0-2,000 ft (0-610m) OFF OFF
2,001-5,400 ft (610-1,646 m) OFF ON
SWITCH
O
F
F
ON
1
2
3
4
5
6
7
8
COMMUTATEUR
O
F
F
ON
1
2
3
4
5
6
7
8
SWITCH
O
F
F
ON
1
2
3
4
5
6
7
8
COMMUTATEUR
O
F
F
ON
1
2
3
4
5
6
7
8
Checklist for Gas and Electricity
□A manual gas control valve is placed in the gas line to the water
heater.
□Check the gas lines and connections for leaks.
□Confirm that the gas inlet pressure is within limits.
□Confirm that the water heater is rated for the gas type supplied.
□Confirm that the electricity is supplied from 120 VAC, 60 Hz
power source and is in a properly grounded circuit.
□An extension cord or an adapter plug has not been used with
the water heater.
INSTALLATION INSTRUCTIONS

1716
Installation CheckList
•The water heater is not exposed to corrosive compounds in the air.........................................................................................................
•The water heater location complies with the clearances. ..........................................................................................................................
•The water supply does not contain chemicals or exceed total hardness that will damage the heat exchanger. ........................................
•Ensure the water heater and its water lines are protected from freezing. Damage due to freezing is not covered by the warranty...........
•Confirm that the electricity is supplied from a 120 VAC, 60 Hz power source, is in a properly grounded circuit, and turned on..............
•The installation must conform with local codes or, in the absence of local codes, with the National Fuel Gas Code,
ANSI Z223.1/NFPA 54, or the Natural Gas and Propane Installation Code, CSA B149.1...........................................................................
•Verify proper clearances around the vents and air intakes........................................................................................................................
•Ensure that the Combustion Air Requirements are followed that will provide sufficient combustion air for the appliance. ......................
•Ensure you have used the correct venting products for the model installed and that you have completely followed the venting
manufacturer’s installation instructions and these installation instructions..............................................................................................
•The water heater must be vented vertically to the outside of the building or structure. ............................................................................
•Purge the water line of all debris. Debris will damage the water heater. Use a bucket or hose, if necessary. ...........................................
•Ensure the water heater is vented in accordance with National Fuel Gas Code, ANSI Z223.1/NFPA 54 - latest edition and the
requirements of state or local codes.........................................................................................................................................................
•Ensure that hot and cold water lines are not crossed to the unit and are leak-free. ..................................................................................
•Clean the inlet water filter by first powering OFF the water heater. Remove the lower enclosure. Drain and relieve the pressure
from the system. Remove and clean the filter of any debris that may reduce water flow. Once clean, replace the filter. Close the
drain valve and pressurize the system. Power the unit back ON and set desired temperature. For more information on cleaning
the filter, please see page 26 section C.....................................................................................................................................................
•Ensure that the temperature/pressure relief valve is installed...................................................................................................................
•Check for proper water pressure to the water heater. Minimum water pressure is 20 psi. A water pressure of 30-50 psi is
recommended for maximum performance. ..............................................................................................................................................
•A manual gas control valve has been placed in the gas line to the water heater. ......................................................................................
•Check the gas lines and connections for leaks..........................................................................................................................................
•Confirm that the gas inlet pressure is within limits...................................................................................................................................
•Confirm that the water heater is rated for the gas type supplied...............................................................................................................
•An extension cord or an adapter plug has not been used with the water heater. ......................................................................................
•Verify the system is functioning correctly by connecting your manometer to the gas pressure test port on the water heater.
Operate all gas appliances in the home or facility at high fire. The inlet gas pressure at the water heater must not drop below
that listed on the rating plate. ...................................................................................................................................................................
•Ensure the lower enclosure is installed.....................................................................................................................................................
•Explain to the customer the importance of not blocking the vent termination or air intake.......................................................................
•Explain to the customer the operation of the water heater, safety guidelines, maintenance, and warranty...............................................
•Inform the consumer of the importance of good water quality and its effects on the warranty. ...............................................................
• Leave the entire manual taped to the water heater or give the entire manual directly to the consumer. ...............................
INSTALLATION INSTRUCTIONS

18
Specifications
Model UG40-92TFTT-N2U or UG40-92TFTT-P2U
Minimum Gas Consumption BTU/hr Natural Gas: 59,500 BTU/hr
Propane: 47,600 BTU/hr
Maximum Gas Consumption BTU/hr Natural Gas: 91,300 BTU/hr
Propane: 87,300 BTU/hr
First-Hour Rating 180 GPH
Storage Tank Volume 40 gallons (151.5 litres)
Recovery (90° Rise) 90 GPH
Temperature Selections 110,120,130,135,140
Maximum Temperature Setting 140oF (60oC)
Minimum Temperature Setting 110oF(43oC)
Weight 150 lbs.(68 kg)
Thermal Efficiency 80 %
Noise level 50 dB
Electrical Consumption
Standby 3 Watts
Operation 150 Watts
Fuse 5 Amps
Minimum Gas Supply
Pressure
Natural Gas 4.0 inches (10.2 cm) W.C.
Propane 8.0 inches (20.3 cm) W.C.
Maximum Gas Supply
Pressure
Natural Gas 10.5 inches (26.7 cm) W.C.
Propane 13.5 inches (34.3 cm) W.C.
Type of Appliance Automatic Circulating Tank Water Heater
Approved Gas Type Natural Gas or Propane - Ensure unit matches gas type supplied at
the installation location.
Connections Gas Supply: 1/2” (1.3 cm) MNPT, Cold Water Inlet: 3/4” (1.9 cm) MNPT,
Hot Water Outlet: 3/4” (1.9 cm) MNPT
Ignition System Direct Electronic Ignition
Electric Connections Appliance: AC 120 Volts, 60Hz
Water Temperature Control Simulation Feedforward and Feedback
Water Supply Pressure Minimum Water Pressure: 20 PSI (Recommended 30-50 PSI for
maximum performance)
Maximum Water Supply Pressure 150 PSI
Sensor and Switches
Flammable Vapor Sensor
Combustion Air Co Sensor
Bi-Metal Overheat Switch
Giant is continually updating and improving products. Therefore, specifications are subject to change without prior notice.
The maximum inlet gas pressure must not exceed the value specified by the manufacturer. The minimum value listed is for the purpose of
input adjustment.
TECHNICAL DATA

1918
TECHNICAL DATA
51.2”
(130.0 cm)
48.6”
(123.4 cm)
27.5”
(69.8 cm)
26”
(66.0 cm)
8”
(20.3 cm)
23.8”
(60.5 cm)
20”
(50.8 cm)
24.8”
(63.0 cm)
25.8”
(65.5 cm)
27.5”
(69.8 cm)
18.7”
(47.5 cm)
10”
(25.4 cm)
51,2”
(130,0 cm)
48,6”
(123,4 cm)
27,5”
(69,8 cm)
26”
(66,0 cm)
8”
(20,3 cm)
23,8”
(60,5 cm)
20”
(50,8 cm)
24,8”
(63,0 cm)
25,8”
(65,5 cm)
27,5”
(69,8 cm)
18,7”
(47,5 cm)
10”
(25,4 cm)
Dimensions
Figure 14

20
Wire Color Legend
W:.....WHITE
BK:….BLACK
BR:….BROWN
R:…...RED
BL:….BLUE
Y:…...YELLOW
P:…...PINK
O:…...ORANGE
GY:….GRAY
Légende des couleurs de fils
W :.....BLANC
BK :….NOIR
BR :….BRUN
R :…...ROUGE
BL:….BLEU
Y:…...JAUNE
P:…...ROSE
O:…...ORANGE
GY:….GRIS
DÉTECTEUR DE
DÉBIT D’EAU
THERMISTANCE
DU RÉSERVOIR
THERMISTANCE
DE SORTIE
THERMISTANCE
DU BRÛLEUR
DÉTECTEUR DE VAPEURS INFLAMMABLES
FUSIBLES THERMIQUES
VENTILATEUR DE COMBUSTION
INTERRUPTEUR
HAUTE TEMPÉRATURE
ÉLECTROVANNE À MODULATION
ÉLECTRODE DE FLAMME
ÉLECTROVANNE PRINCIPALE
ÉLECTROVANNE 1 (PETITE)
ÉLECTROVANNE 2 (GRANDE)
ALLUMAGE
ÉLECTRODE
D’ALLUMAGE
DÉTECTEUR DE DÉBIT D’EAU
DISPOSITIF DE CONTRÔLE
DU DÉBIT D’EAU
CIRCUIT DE
DÉTECTION DU
DÉBIT D’EAU
CIRCUIT DU DISPO-
SITIF DE CONTRÔLE
DU DÉBIT D’EAU
FUSIBLE
THERMIQUE
INTERRUPTEUR
HAUTE
TEMPÉRATURE
CIRCUIT DE
COMMANDE
FET 1
CIRCUIT DE
COMMANDE
DE
L’ÉLECTRO-
VANNE
THERMISTANCE DU
RÉSERVOIR
CIRCUIT
DE
THERMI-
STANCE
THERMISTANCE DE
SORTIE D’EAU
THERMISTANCE DU
BRÛLEUR
DÉTECTEUR DE CO
CIRCUIT DE
DÉTECTION DE CO
CIRCUIT DE DÉTECTION
DE VAPEURS
INFLAMMABLES
DÉTECTEUR DE
VAPEURS
INFLAMMABLES
UNITÉ DE
COMMANDE
CIRCUIT
D’UNITÉ DE
COMMANDE
CIRCUIT DE
DÉTECTION DE
FLAMMES
ÉLECTRODE DE
FLAMME
CIRCUIT DE
CONTRÔLE DU
VENTILATEUR
UNITÉ
CENTRALE
VENTILATEUR DE
COMBUSTION
CIRCUIT DE
CONTRÔLE DE LA
PUISSANCE DE
L’ÉLECTROVANNE
À MODULATION
ÉLECTROVANNE À
MODULATION
POSITIF
NEUTRE
MISE À LA TERRE
FUSIBLE
(5A)
DISPOSITIF
ANTISURTENSION
POMPE
DISPOSITIF DE CONTRÔLE
DU DÉBIT D’EAU
UNITÉ DE
COMMANDE
PRESSION DU GAZ
TYPE DE GAZ
AJUSTEMENT DE COURANT DE
L’ÉLECTROVANNE À MODULATION
DÉTECTEUR DE CO
UNITÉ DU
CONTRÔLE AU GAZ
COULEUR DE FIL
POUR LA
CONNEXION DE
L’ÉLECTROVANNE
POSITIF NEUTRE
FUSIBLE (5A)
DÉCHARGEUR
DE FOUDRE
VARISTANCE
VARISTANCE
RELAIS 2 POMPE
ALLUMAGE
RELAIS 1
ALIMENTATION
ÉLECTRIQUE À
COMMUTATION
TECHNICAL DATA
Wiring Diagram
Figure 15