GE GN75DNSRSA User manual

1
49-50229-1 03-08 JR
Installation Indoor Direct Vent Tankless Water Heater
Instructions Models GN75DNSRSA, GN94DNSRSA, GP94DNSRSA
Questions? Call 888.HOTWTER (888.468.9837) or Visit our website at ge.com
BEFORE BEGINNING INSTA ATION
Read these instructions completely and carefully.
•IMPORTANT —Save these instructions
for local inspector’s use.
•IMPORTANT —Observe all governing
codes and ordinances.
•Note to Installer – Be sure to leave these
instructions with the Consumer.
•Note to Consumer – Keep these instructions
for future reference.
• Proper installation is the responsibility of the
installer.
• Product failure due to improper installation
is not covered under the Warranty.
Recognize this symbol as an indication
of Important Safety Information!
WARNING: Read entire manual. Failure to follow all guides and rules could cause personal
injury or property damage.
• Check with your state and/or local public works department for plumbing codes. You must follow their
guides as you install the Water Heater.
NOTE: Failure to comply with these installation instructions will void the product warranty, and the
installer will be responsible for any service, repair or damages caused thereby.
SAFETY PRECAUTIONS
WARNING: If the information in these
instructions is not followed exactly, a fire or explosion
may result, causing property damage, personal injury
or death.
FOR YOUR SAFETY!
– Do not store or use gasoline or other
flammable vapors or liquids or other
combustible materials in the vicinity of this
or any other appliance. To do so may result
in an explosion or fire.
– WHAT TO DO IF YOU SME 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.
• Do not return to your home until authorized
by the gas supplier or fire department.
– Improper installation, adjustment, alteration,
service or maintenance can cause property
damage, personal injury or death. Refer to
this manual. Installation and service must
be performed by a qualified installer, service
agency or the gas supplier.
• This water heater must be vented outdoors
using approved ducting materials.
• Service information and wiring diagram are
located behind front panel.
• Service must be performed by a qualified
service agency.
• This appliance must be properly grounded and
installed as described in these instructions
.
FOR INDOOR APPLICATIONS ONLY

Installation Instructions
2
SAFETY PRECAUTIONS (cont.)
WARNING: Do not use substitute
materials. Use only parts certified with the
appliance.
• This appliance must be installed, inspected and
leak tested by a state- or city-qualified licensed
contractor. It is the responsibility of the person
having the water heater installed to ensure the
installing contractor has proper licenses and
permits for installing water heaters in your
location. GE highly recommends that installers
attend a product knowledge class to ensure
customer satisfaction and warranty coverage.
Failure to comply with state and local codes
pertaining to water heater installations may
void the warranty.
• This appliance is not to be installed outdoors.
• 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.
• The appliance and its appliance main gas valve
must be disconnected 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 system by closing its individual
manual shut-off valve during any pressure
testing of the gas supply piping system at test
pressures equal to or less than 1/2 psi (3.5 kPa)
(13.84 in W.C.).
• Carefully follow the venting instructions
beginning on page 19 and in the Maintenan e
section in the Owner’s Manual for adequate
combustion and ventilation air.
• The appliance should be located in an area
where water leakage of the unit or connections
will not 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
airflow.
SAFETY PRECAUTIONS (cont.)
•The flow of combustion and ventilation air shall
not be obstructed.
• This appliance is not suitable for use in an
application such as a pool or spa heater that
uses chemically treated water. (This appliance
is suitable for filling large or whirlpool bath tubs
with potable water.)
• If a water heater is installed in a closed-water
supply system, such as one having 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 this situation.
• 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 (at the flue terminal external
to the home) location free of chemicals, such as
chlorine or bleach, that produce fumes. These
fumes can damage components and reduce
the life of your appliance.
CAUTION: DO NOT operate the water
heater if any part of the appliance has been under
water.
CAUTION: BURN HAZARD. ot exhaust
and vent may cause serious burns. Keep back from
water heater unit. Keep small children and animals
away from unit.
CAUTION: ot Water outlet pipes leaving
unit can be hot to touch. Insulation must be used
for hot water pipes below 36″due to burn risk to
children.
WARNING: This unit is not intended
or qualified for use in manufactured homes, mobile
homes or recreational vehicles.
DANGER
Read and follow water heater warnings and
instructions. If owner’s manual is missing, contact
the retailer or manufacturer.

3
Installation Instructions
TOO S YOU WI NEED
• Pipe Wrenches (2) • Gloves
• Adjustable Pliers • Safety Glasses
• Screwdrivers (2)
• Wire Cutters
MATERIA S YOU WI NEED TO SUPP Y
• Soap Solution • Pipe Fittings Required:
• Pipe Compound – Unions
• Approved Venting – Ball Valves
• 5/8″ID PVC Flexible – Drain Valves
Tubing – Pressure Relief Valve
• 2 Conductor 22 AWG Wire for Remote Control
• Single Gang Electrical Box
• Wire Nuts
• Concrete Wall Anchors (Optional)
Your installation components may vary.
PARTS PROVIDED
Locate the parts packed with the Water eater.
Gas Valve 3/4″FNPT Ball Valve
4 #10 x 11⁄4″
Wood Screws
OTHER TOO S THAT MIGHT BE REQUIRED
• ammer Drill with Concrete Bits
• Saw
• Threading Machine with eads and Oiler
• Core Drill with Diamond ead
• Torch Set
• Copper Tubing Cutter
• Steel Pipe Cutter
OTHER MATERIA S THAT MIGHT BE NEEDED
• eat Tape
• Pipe Insulation
• Electrical Wire and Conduit per Local Code
• Air Inlet Screen
• Optional Pipe Cover AGTPCM
• Optional Remote Controller AGTRC1

4
Installation Instructions
DIMENSIONS
*This is the minimum dimension from the wall. The wall bracket is adjustable to allow an additional 1.57 inches (40 mm).
GN75/GN94/GP94DNSRSA
DIM. DESCRIPTION IN. (MM)
A Width 14 (355.6)
B Depth 95⁄8(244.5)*
C eight – Unit 227⁄8(582)
D eight – with brackets 251⁄2(647.7)
E ot Water Outlet – from wall 35⁄8(91)*
F ot Water Outlet – from center 45⁄16 (110)
G Cold Water Inlet – from wall 213⁄16 (70)*
Cold Water Inlet – from center 11⁄8(27)
I Gas Connection – from wall 37⁄8(99)*
J Gas Connection – from center 31⁄2(89)
From base to gas connection 15⁄8(40)
K From base to cold connection 2 (50)
From base to hot connection 15⁄8(41)
A
C
D
K
B
EH
FJ
GI

5
Installation Instructions
P ANNING FOR VENTING
INTAKE/EXHAUST GUIDE INES
Refer to the specific instructions on your vent
product for additional installation requirements.
• This water heater is a direct vent water heater and
therefore is certified and listed with the vent system.
You must use vent components that are certified
and listed with the water heater model. See
approved venting list on page 20.
• Do not combine vent components from different
manufacturers.
• The vent system must vent directly to
the outside of the building and use outside
air for combustion.
• Every vent connection must be accessible for
inspection, cleaning and replacement.
• Avoid dips or sags in horizontal vent runs by
installing supports per the vent manufacturer’s
instructions.
• Support horizontal vent runs every four feet
and all vertical vent runs every six feet or in
accordance with local codes.
• Venting should be as direct as possible with
a minimum number of pipe fittings.
• Vent diameter must not be reduced.
• Do not connect the venting system with
an existing vent or chimney.
• Do not connect vent with the vent pipe of any other
water heater or appliance.
• Vent connections must be firmly pressed together
so that the gaskets form an air-tight seal.
• The vent piece connected to the water heater must
be secured with one self-tapping screw.
• Refer to the vent pipe manufacturer’s instructions
for component assembly instructions.
• It is recommended to install an optional inlet screen
to minimize blockage and maintenance from debris.
See page 20.

F UE TERMINA C EARANCES (ANSI Z21.10.3 • CSA 4.3)
6
Installation Instructions
F UE TERMINA C EARANCES
U.S. INSTA ATIONS
C EARANCES PER
REF DESCRIPTION ANSI Z21.10.3
A Clearance above grade, veranda, porch, deck or snowline 36 inches (91 cm)
B Clearance to window or door that may be opened 12 inches (30 cm)
CClearance to permanently closed window *
D Vertical clearance to ventilated soffit, located above the terminal within *
a horizontal distance of 2 feet (61 cm) from the center line of the terminal
E Clearance to unventilated soffit *
F Clearance to outside corner *
G Clearance to inside corner *
Clearance to each side of center line extended above meter/regulator *
assembly
I Clearance to service regulator vent outlet *
J Clearance to nonmechanical air supply inlet to building or 12 inches (30 cm)
the combustion air inlet to any other appliance
K Clearance to a mechanical air supply inlet 3 feet (91 cm) above
if within 10 feet
(3 m) horizontally
L Clearance above paved sidewalk or paved driveway located on public property1*
M Clearance under veranda, porch, deck or balcony2*
*For clearances not specified in ANSI Z223.1/NFPA 54, clearances are in accordance with local installation codes and the requirements of the gas supplier.
Clearance to opposite wall is 24 inches (60 cm).
1 A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
2 Permitted only if veranda, porch, deck or balcony is fully open on a minimum of two sides beneath the floor.

7
Installation Instructions
ADDITIONA C EARANCES – VENT TERMINA
These clearances are applicable to both concentric terminations and nonconcentric vent exhaust terminations.
Local codes supersede these clearances.
• Avoid termination locations near a dryer vent.
• Avoid termination locations near commercial cooking exhaust.

Installation Instructions
8
F UE INSTA ATION – CONDENSATE DRAIN
HORIZONTA TERMINATION WITH VERTICA TERMINATION (condensate collector
A CONDENSATE DRAIN required in all installations)
3 in (75 mm)
minimum

Installation Instructions
9
P ANNING FOR P UMBING
(shown with optional pipe cover)
The center of the pipes can be placed anywhere
within the shaded area. The center of the pipes
is recommended to be protruding only within 6″
of the mounting wall. Other specific installations
may be different.
Be sure that the minimum elevation of the bottom
of the unit is 16″to meet the 36″recommended
clearance for the exhaust.
CAUTION: BURN HAZARD. ot exhaust and
vent may cause serious burns. Keep back from water
heater unit. Keep small children and animals away
from unit.
CAUTION: ot Water outlet pipes leaving unit
can be hot to touch. Insulation must be used for hot
water pipes below 36″due to burn risk to children.
NOTE: It is recommended to install the bottom
of the unit at least 18″off the ground to minimize
blockage and maintenance from debris and provide
room for the optional Pipe Cover Accessory Model
Number AGTPCM.
NOTE: Do not install electrical outlet directly
below unit. Electrical outlet must be installed
less than 6 feet from unit.
Gas
Water
through
the wall
Un t
Water and Gas
from below
12″
12″
21⁄2″
6″
21⁄2″21⁄2″
41⁄2″
61⁄2″
18″m n.
Floor
7″
97⁄8″
21⁄2″
9″
12″
33⁄8″
Opt onal P pe Cover
(AGTPCM) shown shaded.
P pe cover not requ red,
However, cons derat on
should be taken n
the des gn of the rough
plumb ng to allow
nstallat on of un t
and p pe cover.
Suggested area for
Water and Gas l nes to
come through the wall
so the opt onal p pe
cover can be nstalled,
f des red.

10
Installation Instructions
CORROSIVE ATMOSPHERES
NOTICE: The water heater or intake air supply
should not be installed near an air supply
containing halogenated hydrocarbons
or near swimming pool chemicals.
MOUNTING THE WATER HEATER
CAUTION: Reinforcement of the
wall is required in case the wall is not strong
enough to hold the water heater. Do not mount
to drywall unless mounting screws are secured
in wall studs.
Make sure the location of the water heater allows
for easy access and operation.
Wall studs should be utilized when mounting the
water heater to the wall. On masonry or concrete
wall, use concrete anchors or lag bolts.
Identify the installation location and confirm
that the installation will meet all required
clearances. Use mounting template
to locate screw and anchor locations.
Securely attach the water heater to the wall
using the brackets located at the top and
bottom of the water heater.
Ensure that the attachment strength is
sufficient to support the weight. Refer to the
weight of the water heater in the Spe ifi ation
Guidelines. Four mounting screws with 200 lb.
tensile load capability are required at
a minimum.
3
2
1
Wall nstallat on
brackets
C EARANCES FOR WATER HEATER
WARNING: 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.
To front
To top
To s de
To floor/ground
*Every vent connection must be accessible for inspection, cleaning
and replacement.
To combustibles To noncombustibles
Top of heater 6 inches (152 mm) 2 inches (51 mm)
Back of heater 0 (zero) 0 (zero)
Front of heater 6 inches (152 mm) 6 inches (152 mm)
Sides of heater 2 inches (51 mm) 1/8 inch (3 mm)
Floor/ground 12 inches (305 mm) 12 inches (305 mm)
Vent 0 (zero) 0 (zero)
Closet 6 inches (152 mm) 6 inches (152 mm)
from front from front

MOUNTING THE WATER HEATER (cont.)
FINISHED WA S (Drywall) Option 1:
Mount boards over drywall directly to studs
in the wall. When attaching the unit to a finished
wall, mount two boards suitable for anchoring
to wall studs. Level the unit during installation.
NOTE: Do not hang the unit on drywall only. The
unit must be secured into wood mounting board.
FINISHED WA S (Drywall) Option 2:
Framed wall with boards behind the drywall.
Mount the unit to boards in the wall. Do not use
the screws provided to mount through drywall.
Screws long enough to penetrate the drywall
and provide at least 1″of engagement in wood
should be used. Screws should be rated to carry
a tensile load of 200 lbs each. Level the unit
during installation.
NOTES:
• Screws provided must fasten securely
and directly into wood. If screws go through
drywall and do not fully engage the wood stud,
the installer must supply correct screws.
• Do not hang the unit on drywall only. The unit
must be secured into wood mounting board.
4
MOUNTING THE WATER HEATER (cont.)
ON MASONRY OR CEMENT WA : Mount
4 wall anchors (not supplied) in a wall suitable
to carry 200 lbs minimum tensile load each.
Level the unit during installation.
IMPORTANT: Anchors suitable for masonry
or concrete are to be supplied by the installer.
11
Installation Instructions
Boards on outs de of f n shed wall
Boards on ns de of f n shed wall
243⁄4″
243⁄4″

12
Installation Instructions
GAS PIPING (cont.)
PIPE SIZING PROCEDURE
The gas supply to the home must be capable
of handling the entire gas load of the home,
calculated by adding the BTU rating of each gas
appliance in the home. State and local codes must
be met, as well as utility requirements, to ensure
gas supply to the unit is adequate to meet the
rated demand. Use the charts below as a guide to
size the pipe from the utility meter to the tankless
water heater. Gas line sizing is based on gas type,
the pressure drop in the system, the gas pressure
supplied and the gas line type. Refer to the National
Fuel Gas Code, NFPA 54, and/or your local gas
provider, for proper gas line sizing.
1
GAS PIPING
GENERA INSTRUCTIONS
• Make sure gas supply is off prior to making
any connections to the water heater. A manual
gas control valve, provided with this water
heater, 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 connecting 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 location provided by the gas
company. Supplied gas pressure must be within
the limits shown in the Spe ifi ations section.
• Before placing the appliance in operation, all
joints, including the heater, must be checked for
gas tightness by means of leak detector solution,
soap and water or an equivalent nonflammable
solution, as applicable. (Since some leak test
solutions, including 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.)
• Always use approved connectors to connect the
unit to the gas line. Always purge the gas line of
any debris before connection to the water heater.
• 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.
• 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).
•Refer to an approved pipe sizing chart
if in doubt about the size of the gas line.
1
CONNECTING THE WATER HEATER TO GAS AND WATER
PIPE SIZING TAB E – NATURA GAS
cubic feet per hour Schedule 40 Metallic Pipe
Inlet Pressure: less than 2 psi (55 inches W.C.)
Pressure Drop: 0.3 inches W.C.
Specific Gravity: 0.60
PIPE SIZE (INCHES)
ength 3/4 11
1/411/2
10 273 514 1060 1580
20 188 353 726 1090
30 151 284 583 873
40 129 243 499 747
50 114 215 442 662
60 104 195 400 600
70 95 179 368 552
80 89 167 343 514
90 83 157 322 482
100 79 148 304 455
125 70 131 269 403
150 63 119 244 366
175 58 109 224 336
200 54 102 209 313
PIPE SIZING TAB E – PROPANE GAS
cubic feet per hour Schedule 40 Metallic Pipe
Inlet Pressure: 11.0 inches W.C.
Pressure Drop: 0.5 inches W.C.
Specific Gravity: 1.50
PIPE SIZE (INCHES)
ength 1/2 3/4 11
1/4
10 291 608 1150 2350
20 200 418 787 1620
30 160 336 632 1300
40 137 287 541 1110
50 122 255 480 985
60 110 231 434 892
80 101 212 400 821
100 94 197 372 763
125 89 185 349 716
150 84 175 330 677
175 74 155 292 600
200 67 140 265 543

13
Installation Instructions
CONNECTING THE WATER HEATER
TO THE GAS SUPP Y
2
Connect the gas supply to the system following
state and local plumbing codes. Use the supplied
ball valve at the inlet to the system. Make sure
the gas supply line to the water heater fits in the
diagram shown on page 9. This is essential if a pipe
cover accessory (model number AGTPCM) is to be
installed.
IMPORTANT: Use a pipe wrench to securely
hold on to the end of the water heater gas inlet
to prevent twisting the inlet.
IMPORTANT: Leave the gas valve off until
instructed to turn it on.
Gas Shut Off Valve
Gas Supply
Gas Pressure Test Port

14
Installation Instructions
WATER PIPING
GENERA INSTRUCTIONS
• The water supply should be shut off while
connecting the water heater. Make sure the
water inlet and outlet lines to the water heater fit
in the diagram shown on page 9. A manual water
control valve must be placed in the water inlet
connection to the water heater before it is
connected to the water line. Unions can be
used on both the hot and cold water lines for
future servicing and disconnection of the unit.
• The piping (including soldering materials) and
components connected 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.
• Toxic chemicals such as those used for boiler
water treatment are not to be introduced to the
potable water used for space heating.
• 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 nonpotable
water heating appliance.
• Ensure that the water filter on the water heater
is clean and installed. See the Cleaning the inlet
filter section in the checklist on page 23.
• New plumbing typically has contamination
in the lines. The inlet water filter should be
cleaned immediately after initial use.
CAUTION: ot Water outlet pipes leaving
unit can be hot to touch. Insulation must be used
for hot water pipes below 36″due to burn risk to
children.
PRESSURE RE IEF VA VE
• Make sure the pressure relief valve is installed
so there is clearance if the optional pipe cover
(AGTPCM) is installed.
• An approved pressure relief valve is required
by the Ameri an National Standard (ANSI
Z21.10.3)/Canadian Standard (CSA 4.3)
for all water heating systems.
• The relief valve must comply with the standard
for Relief Valves and Automati Gas Shutoff
Devi es for Hot Water Supply Systems (ANSI
Z21.22) and/or the standard Temperature,
Pressure, Temperature and Pressure Relief
Valves and Va uum Relief Valves, CAN1-4.4.
3WATER PIPING (cont.)
PRESSURE RE IEF VA VE (cont.)
• The relief valve must be rated up to 150 psi and
to at least the maximum BTU/hr of the appliance.
• The discharge from the pressure relief valve
should be piped to the ground or into a drain
system to prevent exposure or possible burn
hazards to humans or other plant or animal life.
Follow local codes. Water discharged from the
relief valve could cause severe burns instantly,
scalds or death.
• The pressure relief valve must be manually
operated once a year to check for correct
operation.
• The relief valve should be added to the hot water
outlet line according to the manufacturer’s
instructions. DO NOT place any other type of
valve or shut-off device between the relief valve
and the water heater.
• Do not plug the relief valve and do not install any
reducing fittings or other restrictions in the relief
line. The relief line should allow for complete
drainage of the valve and the line.
• If a relief valve 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
situation. Do not plug the relief valve.
• Neither GE nor the Ameri an National Standard
(ANSI Z21.10.3)/Canadian Standard (CSA 4.3)
requires a combination temperature and
pressure relief valve for this appliance; however,
local codes may require a combination
temperature and pressure relief valve.
INTERNA BUI T-IN FREEZER PROTECTION
• The freeze protection features include
electrical heating elements and intermittent firing
of the burner. Freeze protection may be disabled
if electricity or gas is not supplied, or if there is
an error preventing the water heater from
functioning.
NOTE: See SUPPLEMENTAL FREEZE PROTECTION
on page 15.
3
CONNECTING THE WATER HEATER TO GAS AND WATER (cont.)

15
Installation Instructions
CONNECTING THE WATER HEATER
TO THE WATER SUPP Y
Water connections to the tankless water heater
should follow all state and local plumbing codes.
If this is a standard installation, refer to
the diagram on the following page under
RECOMMENDED PIPING FOR BASIC INSTALLATION.
If freeze protection valves are being installed, refer
to the diagram under FREEZE PROTECTION FOR
EXTERNAL PIPING on page 17.
1. Plumb water supply to the tankless water heater
on the 3/4″MNPT connection at the bottom of
the unit marked WATER INLET.
2. Plumb the home hot water supply to the 3/4″
MNPT connection marked WATER OUTLET
at the bottom of the unit.
NOTE: Make sure water lines to the water heater fit
in the diagram shown on page 9. This is essential if
a pipe cover accessory (model number AGTPCM) is
to be installed.
SUPP EMENTA FREEZE PROTECTION
If the unit is installed in an environment that can
freeze, follow state and local codes and apply heat
trace to ALL water pipe and fittings located outside
(attic, crawl space or building structure).
It is highly recommended in areas where freezing
temperatures occur to install automatic drain
valves that work in the event of a power loss.
Refer to the diagram in the FREEZE PROTECTION
FOR EXTERNAL PIPING section (page 17). These
valves should be wired to a supply current.
In the event of a power loss, the system will
drain automatically. Be sure to test this system
after installation by turning off power to ensure
the system drains properly.
Cold Inlet
Shut Off Valve
Pressure Rel ef
Valve
Hot Outlet
Shut Off Valve

16
Installation Instructions
RECOMMENDED PIPING FOR BASIC INSTA ATION
This is not an engineered drawing; it is intended
only as a guide and not as a replacement for
professionally engineered project drawings. This
drawing is not intended to describe a complete
system; it is up to the contractor/engineer to
determine the necessary components for and
configuration of the particular system being
installed. The drawing does not imply compliance
with local building code requirements; it is the
engineer‘s/contractor’s responsibility to ensure
the installation is in accordance with all local
building codes. Confer with local building officials
before installation.
3/4″Ball Valve
3/4″Un on
Pressure Rel ef Valve
Bo ler Dra n Valve
KEY
NOTE: If un t s nstalled n an
env ronment that can freeze, follow
state and local codes and apply
heat trace to ALL water p pes and
f tt ngs located outs de (att c, crawl
space or bu ld ng structure).

FREEZE PROTECTION
FOR EXTERNA PIPING
IMPORTANT!
With electrical power supplied to the water
heater, it will not freeze in environments as
cold as -30°F, when protected from direct wind
exposure.
In the event of a power failure at temperatures
below freezing, the water heater should be
drained of all water to prevent freezing damage.
The unit may be drained manually, or through
the installation of the optional solenoid valves
as shown.
The unit may be drained manually; however, we
highly recommend that drain-down solenoid valves
be installed that will automatically drain the unit if
power is lost.
When the electrical power to the water heater
fails, the 3/4″solenoid valve closes (stopping
the flow of water into the heater) and the 1/4″
solenoid valve opens (allowing the water heater
and associated piping to drain). Ensure that you
run the drain for the solenoids to the outside
environment to prevent discharging water inside
the building, which can cause water damage.
NOTE: If the unit is installed in an environment that
can freeze, follow state and local codes and apply
heat trace to ALL water pipes and fittings located
outside (attic, crawl space or building structure).
17
Installation Instructions
This is not an engineered drawing; it is intended
only as a guide and not as a replacement for
professionally engineered project drawings. This
drawing is not intended to describe a complete
system; it is up to the contractor/engineer to
determine the necessary components for and
configuration of the particular system being
installed. The drawing does not imply compliance
with local building code requirements; it is the
engineer‘s/contractor’s responsibility to ensure
the installation is in accordance with all local
building codes. Confer with local building officials
before installation.
3/4″Ball Valve
3/4″Un on
Check Valve
Pressure Rel ef Valve
Pressure Regulator
C rculat ng Pump
Bo ler Dra n Valve
Soleno d Valve
SS
KEY

18
Installation Instructions
E ECTRICA CONNECTION
INFORMATION
WARNING – To reduce the risk
of fire, electrical shock and personal injury:
• Do not use an extension cord or an adapter plug
with this appliance.
• 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, or the CANADIAN ELECTRICAL CODE,
CSA C22.1.
E ECTRICA REQUIREMENTS
This appliance must be supplied with 120V, 60 z,
and connected to a properly grounded branch
circuit, protected by a 15- or 20-amp circuit
breaker or time-delay fuse.
If electrical supply provided does not meet the
above specifications, it is recommended that a
licensed electrician install an approved outlet.
WARNING – This water heater is
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.
ENSURE PROPER GROUND EXISTS BEFORE USE.
DO NOT REMOVE GROUND PRONG.

19
Installation Instructions
VENTING INSTRUCTIONS (cont.)
MAXIMUM VENT ENGTH
Maximum System performance is achieved
at a vent length of 21 equivalent feet or less. The
system is capable of 41 equivalent feet vent length
if required, but this reduces system performance.
For vent length calculation, a 90-degree elbow
counts as 6 feet and a 45-degree elbow counts
as 3 feet.
Determine the number of 90-degree elbows in
the vent system. (Two 45-degree elbows count
as one 90-degree elbow.)
Refer to the table to find the maximum vent
length based on the number of elbows.
Use the chart below to compute maximum
permissible lengths for venting to outdoors.
NOTE: Factory unit is set to vent up to 21 ft.
for maximum performance. The unit can be
reconfigured to 41 ft. See below or call
1.888. OTWTER.
VENT ENGTH CA CU ATIONS
Total vent length = # straight ft. + # 90-degree
elbow x 6 ft. + # 45-degree elbow x 3 ft.
2
1
CONCENTRIC VENT PIECE EQUIVA ENT ENGTH
Straight 1 ft. (per foot length)
90-degree elbow 6 ft. each
45-degree elbow 3 ft. each
VENTING INSTRUCTIONS
Refer to the specific instructions on your vent
product for additional installation requirements.
CONDENSATE
Regions of cold climate will create more
condensate in the vent system.
Condensate formation can even occur in
high-efficiency direct vent appliances. To prevent
condensate damage, follow these instructions:
• First remove the black plastic cap, and use 5/8″
ID flexible PVC tubing to drain condensate.
• The condensate trap must contain a minimum
of 3 inches (75 mm) of water. See page 8.
• Dispose of condensate per local codes.
• In applications where condensate could freeze,
such as an unconditional attic space, care should
be taken to prevent condensation line freezing.
Refer to state and local codes for proper disposal
of condensate.
WARNING: If the condensate
collector is not used, the drain pipe must be
capped to prevent exhaust gases and condensate
from entering the building. The cap is supplied on
the appliance.
CAUTION: Without proper drainage
or disposal, condensate will damage the heat
exchanger. Condensate collector on the unit
must be properly connected. O
F
F
1
2
3
4
5
6
7
8
ON
Switch No.
SW1
*If the length is greater than
21 ft. (6.4 m), then move dip
switch no. 1 (SW1) to OFF.

20
Installation Instructions
VENTING INSTRUCTIONS
(cont.)
VENT PRODUCTS
Ubbink
Telephone: 888. OTWTER
(888.468.9837)
Heat-Fab
Telephone: [phone]
Web Site: www.heatfab.com
Metal-Fab Inc.
Telephone: [phone]
1.316.943.2351
Web Site: www.metal-fabinc.com
VENT MANUFACTURER CONTACT INFORMATION FOR INSTA ATION INSTRUCTIONS AND PARTS IST
isted and Tested Vent Products for GN75DNSRSA, GN94DNSRSA and GP94DNSRSA (concentric venting)
VENTING INSTRUCTIONS (cont.)
F UE INSTA ATION – CONCENTRIC VENTING
To adjust the condensate collector position:
Loosen the 4 screws at the rear bracket.
Slide the bracket away from the female
vent top.
Remove the 4 screws attaching the female vent
top to the water heater.
Lift up the female vent top and reposition as
desired (or replace with a male vent top).
Install the 4 screws at the vent top and tighten
the 4 screws at the bracket.
Secure the first vent component to the water heater
with one self-tapping screw at the hole located above
the condensate collector.
5
4
3
2
1
Bracket
MANUFACTURER PRODUCT PARTS
Ubbink Rolux Vent System Refer to the manufacturer’s technical literature
eat-Fab Saf-T Vent SC system for specific part numbers and instructions.
Metal-Fab Corr/Guard Vent/ At the time of printing, these manufacturers’
Air Intake System products were listed and tested vent products.
The installer must verify prior to installation if
proper venting is used. For up-to-date approved
vent materials, see http://directories.csa.international.org/
for the CSA Certification record with approved vent materials.