A.O. Smith T-H3S-DV User manual

Gas Tankless Water HeaterTM
Suitable for potable water heating and space-heating
Please refer to local codes for space-heating compliance.
540 (T-H3)
model only
If you have any questions, please
call or write to:
500 Tennessee Waltz Parkway
Ashland City, TN 37015
Toll Free: 1-877-737-2840
WARNING
- Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.
- WHAT TO DO IF YOU SMELL GAS
• Donottrytolightanyappliance.
• Donottouchanyelectricswitch,donot
use any phone in your building.
• Immediatelycallyourgassupplierfrom
a neighbor's phone. Follow the gas
supplier's instructions.
• Ifyoucannotreachyourgassupplier,call
the fire department.
- Installation and service must be performed
by a qualified installer, service agency or the
gas supplier.
On-Demand Water Heater
Installation Manual and Owner’s Guide
ANSI Z21.10.3 and CSA 4.3
If the information in these
instructions is not followed
exactly, a fire or explosion may
result causing property damage,
personal injury or death.
FEATURING
• ENDLESSHOTWATER
• ON-DEMANDUSAGE
• COMPACT,SPACESAVING
• ENERGYCONSERVATION
• COMPUTERIZEDSAFETY
• NOPILOTLIGHT
• Satisfiesthe2012SCAQMDRule
1146.2 for Ultra-Low NOx
Emissions
• EASY-LINKSYSTEMAND
MULTI-UNIT SYSTEM
(540 (T-H3) model only)
Models
• 240Outdoor(T-H3J-OS)
• 340Outdoor(T-H3S-OS)
• 540Outdoor(T-H3-OS)
• 240Indoor(T-H3J-DV)
• 340Indoor(T-H3S-DV)
• 540Indoor(T-H3-DV)
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CONTENTS
Installation Manual
SPECIFICATIONS.......................................................................................................................... 4
INTRODUCTION .......................................................................................................................... 5
SAFETY GUIDELINES.................................................................................................................... 6
INSTALLATION............................................................................................................................. 7
General.....................................................................................................................................7
Clearances................................................................................................................................9
Included accessories................................................................................................................9
Optional items..........................................................................................................................9
Warning for installations........................................................................................................11
High-altitudeinstallations......................................................................................................12
Ventinginstructions...............................................................................................................13
Gas supply and gas pipe sizing...............................................................................................25
Water connections................................................................................................................27
Condensate drain..................................................................................................................28
Electrical connections............................................................................................................30
Temperature remote controller............................................................................................31
Easy-Link System....................................................................................................................33
Multi-UnitSystem..................................................................................................................37
APPLICATIONS............................................................................................................................38
INITIAL OPERATION...................................................................................................................40
Owner's Guide
OPERATING SAFETY .................................................................................................................. 42
NORMAL OPERATION ............................................................................................................... 44
Temperature controller and Remote controller.....................................................................44
General...................................................................................................................................44
Temperaturesettings.............................................................................................................45
Temperature table of controller.............................................................................................45
Additionalfeatures.................................................................................................................46
Temperature settings on the PCB (Without remote controller)............................................47
Flow.......................................................................................................................................48
Freeze protection system.......................................................................................................48
Maintenance and service.......................................................................................................49
Unit draining and filter cleaning............................................................................................49
TROUBLESHOOTING...................................................................................................................50
General...................................................................................................................................50
Error codes............................................................................................................................52
COMPONENTSDIAGRAM...........................................................................................................55
PARTS LIST.....................................................................................................................................59
OUTPUT TEMPERATURE CHART..................................................................................................62
LIMITED WARRANTY..................................................................................................................63
Contents
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Installaon Manual
Installation Manual
CONGRATULATIONS
Congratulations and thank you for choosing our tankless water heater.
Before use, we recommend that you read through this safety manual
carefully. Please refer to the back of the manual for details about the
warranty. Keep this manual for future reference.
If you lose the manual, contact the manufacturer or your local
distributor. When you call, please tell us the model number and the
serial number of your unit written on the rating plate of the water
heater.
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Specicaons
Installaon Manual
SPECIFICATIONS
*40 psi or above is recommended for maximum flow.
** The Manifold Pressure is the factory setting and generally should not need adjustment.
NOTE:
• Checktheratingplatetoensurethisproductmatchesyourspecifications.
• InaccordancewithANSIZ21.10.3,COemissiondoesnotexceed400PPMfornormalinput.
•The manufacturer reserves the right to discontinue, or change at any time, specifications or designs
without notice and without incurring obligation.
Model 240
Indoor
(T-H3J-DV)
240
Outdoor
(T-H3J-OS)
340
Indoor
(T-H3S-DV)
340
Outdoor
(T-H3S-OS)
540
Indoor
(T-H3-DV)
540
Outdoor
(T-H3-OS)
Natural Gas Input
(Operating Range) BTU/h Min.:15,000
Max.:160,000
Min.:15,000
Max.:180,000
Min.:15,000
Max.:199,000
Propane Input
(Operating Range) BTU/h Min.:13,000
Max.:160,000
Min.:13,000
Max.:180,000
Min.:13,000
Max.:199,000
Gas Connection 3/4" NPT
Water Connections 3/4" NPT
Water Pressure* psi
(MPa) 15-150(0.1-1)
Natural gas
Inlet Pressure
" W.C.
(kPa)
Min.5.0(1.24)
Max.10.5(2.61)
Propane
Inlet Pressure
" W.C.
(kPa)
Min.8.0(1.99)
Max.14.0(3.48)
Manifold
Pressure**
Natural
Gas
" W.C.
(Pa)
1.50
(373)
1.70
(423)
2.45
(610)
2.1
(523)
2.95
(734)
2.70
(672)
Propane " W.C.
(Pa)
2.10
(523)
1.90
(473)
2.7
(672)
2.55
(635)
3.3
(821)
3.15
(784)
Weight lbs. (kg) 58(26.3) 58(26.2) 58(26.3) 58(26.2) 59(26.8) 59(26.9)
Dimensions inch H22.4xW17.7xD10.7
H570xW450xD272
mm
Ignition Electric Ignition
Electric
Supply VAC / Hz 120/60
Consumption
Operation W / A 72.7/0.61 78.2/0.65 89.0/0.74
Standby W / A 3.1/0.03 3.1/0.03 4.2 / 0.04
Freeze-
Protection W / A 174/1.5 174/1.5 175/1.5
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INTRODUCTION
•This manual provides information necessary for the installation, operation, and maintenance
of the water heater.
•The model description is listed on the rating plate which is attached to the side panel of the
water heater.
•Please read all installation instructions completely before installing this product.
•If you have any problems or questions regarding this equipment, consult the manufacturer or
its local representative.
•This equipment is an on-demand, tankless water heater designed to efficiently supply endless
hot water for your needs.
•These high efficiency models have a built-in secondary heat exchanger that absorbs latent
heat from the exhaust gas.
•The 240 Indoor (T-H3J-DV), 340 Indoor (T-H3S-DV) and 540 Indoor (T-H3-DV) models are
onlytobeinstalledindoors.The240Outdoor(T-H3J-OS),340Outdoor(T-H3S-OS)and540
Outdoor (T-H3-OS) models are only to be installed outdoors.
•The principle behind tankless water heaters is simple:
*This diagram illustrates tankless water heater design concepts only and does not accurately
represent the water heater’s physical description.
1. A hot water tap is turned on.
2. Water enters the heater.
3. The water flow sensor detects the water flow.
4. The computer initiates the fan motor and sends a signal to the igniter to create an ignition spark.
5. The gas ignites and flames appear within the burner chamber.
6. Water circulates through the heat exchanger and then gets hot.
7. Using thermistors to measure temperatures throughout the water heater, the computer modulates
the gas and water valves to ensure proper output water temperature.
8. When the tap is turned off, the unit shuts down.
Introducon
Installaon Manual
Exhaust
Secondary
heat exchanger
Intake port
Condensate
drain port
Cold water inlet
Gas
Hot water outlet
Computer board Fan motor
Gas valves
Thermistor
Thermistor
Bypass valve
Primary
heat exchanger
Exhaust thermistor
Water control valve
Thermistor
Flow sensor
Burners
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SAFETY GUIDELINES
SAFETY DEFINITION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edition of the National
FuelGasCode:ANSIZ223.1/NFPA54intheUSAorCAN/CSAB149.1NaturalGas,PropaneInstallation
Code in Canada.
2. Properly ground the unit in accordance with all local codes or in the absence of local codes, with the
NationalElectricalCodes:ANSI/NFPA70intheUSAorCSAstandardC22.1CanadianElectricalCode
Part1inCanada.
3. Carefully plan where you intend to install the water heater. Please ensure:
• Yourwaterheaterwillhaveenoughcombustibleairandproperventilation.
• Locateyourheaterwherewaterleakagewillnotdamagesurroundingareas.(Pleasereferto
p. 8.)
4. Check the rating plate for the correct GAS TYPE, GAS PRESSURE, WATER PRESSURE and ELECTRIC
RATING.
*If this unit does not match your requirements, do not install and consult with the manufacturer.
5. If any problem should occur, turn off all hot water taps and turn off the gas. Then call a trained
technician or the Gas Company or the manufacturer.
WARNING
Indicates an imminently hazardous situation which, if not avoided, could result
in death or serious injury.
CAUTION
Indicates an imminently hazardous situation which, if not avoided, could result
in minor or moderate injury.
Safety Guidelines
Installaon Manual
Indicates an imminently hazardous situation which, if not avoided, will result in
death or serious injury.
DANGER
WARNING
• Watertemperaturesover125°F(52°C)cancausesevereburnsinstantlyor
deathfromscalding.Thewatertemperatureissetat120°F(50°C)fromthe
factory to minimize any scalding risk. Before bathing or showering always
check the water temperature.
•Do not store or use gasoline or other flammables, vapors, or liquids in the
vicinity of this appliance.
•Do not reverse the water and/or gas connections as this will damage the gas
valves and can cause severe injury or death. Follow the diagram on p. 27
when installing your water heater.
•Do not use this appliance if any part has been in contact with or been
immersed in water. Immediately call a licensed plumber, a licensed gas
fitter, or a professional service technician to inspect and/or service the unit if
necessary.
•Do not disconnect the electrical supply if the ambient temperature will drop
below freezing. The Freeze Protection System only works if the unit has
electrical power. The warranty will not be covered if the heat exchanger
is damaged due to freezing. Refer to the section on the Freeze Protection
Systemonp.48formoreinformation.
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INSTALLATION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edition of the National
FuelGasCode:ANSIZ223.1/NFPA54intheUSAorCAN/CSAB149.1NaturalGas,PropaneInstallation
Code in Canada.
2. All gas water heaters require careful and correct installation to ensure safe and efficient operation.
This manual must be followed exactly. Read the “Safety Guidelines” Section.
3. The manifold gas pressure is preset at the factory. It is computer controlled and should not need
adjustment.
4. Maintain proper space for servicing. Install the unit so that it can be connected or removed easily.
Refertothe"Clearances"Sectiononp.9forproperclearances.
5. The water heater must be installed in a location where the proper amount of combustible air will be
available to it at all times without obstructions.
6. The electrical connection requires a means of disconnection, to terminate power to the water heater
for servicing and safety purposes.
7. Do not install the unit where the exhaust vent is pointing into any opening in a building or where the
noise may disturb your neighbors. Make sure the vent termination meets the required distance by
local code from any doorway or opening to prevent exhaust from entering a building. (Refer to p. 22.)
8. Particles from flour, aerosols, and other contaminants may clog the air vent, build up and reduce
the functions of the rotating fan, cause improper burning of the gas, or cause damage to the water
heater. Regularly ensure that the area around the unit is dust- or debris-free. Regular maintenance is
recommended for these types of environment.
9. The240Indoor(T-H3J-DV),340Indoor(T-H3S-DV),and540Indoor(T-H3-DV)aretobeinstalled
indoors only. These units are equipped with a thermistor and hi-limit switch for the exhaust gas,
detecting excess temperatures within the flue and enabling the unit to safely stop operations if
needed. These components are always monitoring exhaust gas conditions in order to prevent heat
damage to ABS, PVC, CPVC, or polypropylene (Plastic) venting if ABS, PVC, CPVC, or polypropylene
isused.Iftheexhaustgastemperatureexceeds140°F,thesecomponentswillenabletheunitto
safely stop operations. These components are not installed on the outdoor models since the exhaust
vent is built-in.
•The Indoor model requires a 3 in. or 4 in. make-up intake air supply pipe. The intake pipe must
be sealed airtight.
•Air supply pipe can be made of ABS, PVC, CPVC, polypropylene, corrugated stainless steel, or
Categorylll/IVstainlesssteel.Regardingexhaustpipe,refertop.13and15.
•Sidewall venting is recommended for the Indoor model. Vertical venting (roof termination) is
acceptable.
•The manufacturer recommends running the exhaust vent and the intake pipe as parallel as possible.
10. The240Outdoor(T-H3J-OS),340Outdoor(T-H3S-OS),and540Outdoor(T-H3-OS)modelsonlytobe
installed outdoors and only in the area with mild, temperate climates.
The Outdoor model shall be wall-mounted or mounted on a stand. Locate the Outdoor model in an
open, unroofed area and maintain the following minimum clearances:
There is a 2 in. clearance from the left and right sides of the unit to combustible and
non-combustible surfaces.
Installaon
Installaon Manual
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INCLUDED ACCESSORIES
OPTIONAL ITEMS
•Installation and service must be performed by a qualified installer (for
example, a licensed plumber or gas fitter), otherwise the warranty will be
void.
•The installer (licensed professional) is responsible for the correct installation
of the water heater and for compliance with all national, state / provincial,
and local codes.
•The manufacturer does not recommend installing the water heater in a pit or
location where gas and water can accumulate.
•Do not have the vent terminal pointing toward any operating window, door, or
opening into a building.
•Do not install next to any source of airborne debris, such as a clothes dryer,
that can cause debris to be trapped inside the combustion chamber, unless the
system is direct-vented.
•The manufacturer does not recommend installing the water heater in an attic
due to safety issues. If you install the water heater in an attic:
•Make sure the unit will have enough combustion air and proper
ventilation.
•Keep the area around the water heater clean. When dust collects on the
flame sensor, the water heater will shut down on an error code.
•Place the unit for easy access for service and maintenance.
•A drain pan, or other means of protection against water damage, is
required to be installed under the water heater in case of leaks.
WARNING
•The warranty will not cover damage caused by water quality.
•Only potable water or potable water / glycol mixtures can be used with
this water heater. Do not introduce pool or spa water, or any chemically
treated water into the water heater.
• Waterhardnesslevelsmustnotexceed7grainspergallon(120ppm)for
single family domestic applications or more than 4 grains per gallon (70
ppm) for all other types of applications. Water hardness leads to scale
formation and may affect / damage the water heater. Hard water scaling
must be avoided or controlled by proper water treatment.
• WaterpHlevelsmustbebetween6.5and8.5
•Well water must be treated.
•Do not install the unit where water, debris, or flammable vapors may get into
the flue terminal.
•Although the water heater is designed to operate with minimal sound, the
manufacturer does not recommend installing the unit on a wall adjacent to a
bedroom, or a room that is intended for quiet study or meditation, etc.
•Locate your heater close to a drain where water leakage will not do damage
to surrounding areas. As with any water heating appliance, the potential for
leakage at some time in the life of the product does exist. The manufacturer
will not be responsible for any water damage that may occur. If you install a
drain pan under the unit, ensure that it will not restrict the combustion air flow.
CAUTION
Installaon
Installaon Manual
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Maintain all clearances around
the water heater.
CLEARANCES
Installaon
Installaon Manual
Model Top Bottom Front Back Sides
240 Indoor (T-H3J-DV)
340 Indoor (T-H3S-DV)
540Indoor(T-H3-DV)
12in.
(305mm)
12in.
(305mm)
4 in.*
(102mm)
0.5in.
(13mm)
2 in.
(51mm)
240 Outdoor (T-H3J-OS)
340 Outdoor (T-H3S-OS)
540Outdoor(T-H3-OS)
36in.
(914mm)
12in.
(305mm)
24 in.
(610mm)
0.5in.
(13mm)
2 in.
(51mm)
*24 inches recommended for maintenance.
OPTIONAL ITEMS
Back
Side
Front
Side
Top
Boom
INCLUDED ACCESSORIES
Check that these items below are included with the water heater.
Installation manual
and owner’s guide
Temperature remote controller kit*
Outdoor models only
Bird screen
Indoor models only
Communication cable
540 (T-H3) model only
Qty:1 Qty:1
Qty:1
*Refertop.31.
Qty: 2
#Model
240
Indoor
(T-H3J-DV)
240
Outdoor
(T-H3J-OS)
340
Indoor
(T-H3S-DV)
340
Outdoor
(T-H3S-OS)
540
Indoor
(T-H3-DV)
540
Outdoor
(T-H3-OS)
1. Temperature remote
controller ✓✓✓✓✓✓
2. Pipe cover ✓✓✓✓✓✓
3. Neutralizer kit ✓✓✓✓✓✓
4.
Sidewall vent
terminator (Hood)
and Wall thimble ✓✓✓
5. 3" PVC concentric
termination ✓✓✓
6. Non-return valve ✓✓✓
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Installaon
Installaon Manual
3. Neutralizer kit: 9007607005 (TH-NT01)
The neutralizer assembly neutralizes the condensate (acidic water) that forms in the
secondary heat exchanger of the water heater.
It connects to the condensate drain port of the water heater by using connectors
includedwiththeneutralizerkit.(Refertop.29.)
The temperature remote controller
has two functions. It allows the
output temperature from the water
heater to be adjusted within the range
of100°Fto185°F,anditalsoworks
as a diagnostic tool that will give a
concise error code whenever there is
a problem with the unit.
1. Temperature remote controller:
9008172005 (TM-RE40)
5. 3" PVC concentric termination: 9007611005 (TH-CVPVC33)
Used when terminating direct-vent (sealed combustion)
systems,withIndoormodelsthatrequirea3in.(76mm)intake
anda3in.(76mm)exhaust.
The pipe cover protects the plumbing pipes to
the water heater from unexpected adjustments.
This pipe cover is fixed to the bottom of the water
heater, which hides the plumbing and improves
the visual aspects of the whole installation for
the water heater.
2. Pipe cover: 9008331005 (TH-PC03)
4. Sidewall vent terminator (Hood) and Wall thimble:
They are used when venting out through the wall. These terminations are special stainless steel vents
for gas appliances and are UL listed as Category II, III and IV. For different wall thicknesses, there
are two ranges of lengths available. (Refer to the NovaVent brochure for details.) Install these vent
terminations in accordance with their installation instructions and any applicable local codes.
Covering wall thicknesses Part#
Terminator Hood 9007999005
Wall Thimble 4 - 7 in. 9008345005
WallThimble5-10in. 9008346005
Termination + Thimble 4 - 7 in. 9008004005
Termination+Thimble5-10in. 9008005005
Wall Thimble
Terminator Hood
6. Non-return valve: 9008847005
It is a must-have item for common venting system. It prevents
the escape of combustion gas through non-operating appliances.
(Refertop.20and21.)
The temperature options are 100 °F, 105 °F, 110
°F,115°F,120°F,125°F,130°F,135°F,140°F,145
°F,150°F,155°F,160°F165°F,175°Fand185°F.
See the Troubleshooting Section for information on
possible error codes.
This concentric termination provides the convenience of only having to make one penetration through a
sidewall instead of two separate penetrations for the intake and exhaust piping. The termination includes
a bird screen, restricting small animals, pests, and foreign objects from entering into the vent system.
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