A.O. Smith GPVL-40, GPVT-40, GPVL-50, GPVT-50, GPVX-50L Installation Manual

Installation and Operating Manual

RESIDENTIAL GAS WATER HEATERS

POWER VENTED GAS MODELS

WITH HOT SURFACE IGNITION

NOT FOR USE IN MANUFACTURED (MOBILE) HOMES

• For Your Safety •

AN ODORANT IS ADDED TO THE GAS USED

BY THIS WATER HEATER.

ALL TECHNICAL AND WARRANTY QUESTIONS: SHOULD BE DIRECTED TO THE LOCAL DEALER FROM WHOM THE WATER HEATER WAS PURCHASED. IF YOU ARE UNSUCCESSFUL, PLEASE CONTACT THE COMPANY LISTED ON THE RATING PLATE ON THE WATER HEATER.

KEEP THIS MANUAL IN THE POCKET ON HEATER FOR FUTURE REFERENCE

WHENEVER MAINTENANCE ADJUSTMENT OR SERVICE IS REQUIRED.

1306 322151-003

TABLE OF CONTENTS

TABLE OF CONTENTS 2 SAFE INSTALLATION, USE AND SERVICE 3 GENERAL SAFETY 4 INTRODUCTION 6

Qualiﬁ ed Installer Or Service Agency . . . . . . . . . . . . 6

Preparing For The Installation. . . . . . . . . . . . . . . . . . 6

INSTALLATION REQUIREMENTS FOR THE COMMONWEALTH OF MASSACHUSETTS 7 TYPICAL INSTALLATION 9

Get To Know Your Water Heater - Gas Models (List

Referencing Figures 1-7) . . . . . . . . . . . . . . . . . . . . . 9

Replacement Parts And Deliming Products . . . . . . 10

Combo Heating Inlet And Outlet Side Taps . . . . . . . 10

Water Piping - Mixing Valve Usage . . . . . . . . . . . . . .11

Mixing Valves

Water Heater Operation . . . . . . . . . . . . . . . . . . . . . 12

Electrical Requirements & Wiring Diagram . . . . . . . 13

SAFETY LOCKOUTS 14

High Limit Controls (Energy Cut Off). . . . . . . . . . . . 14

Thermostat/Water Temperature Blower High Limit Switch

Blower Air Pressure Switch. . . . . . . . . . . . . . . . . . . 14

Flammable Vapor Sensor . . . . . . . . . . . . . . . . . . . . 14

LOCATING THE NEW WATER HEATER 15

Facts To Consider About The Location . . . . . . . . . . 15

Storage Of Flammable Liquids . . . . . . . . . . . . . . . . 15

Clearances to combustibles Floors with carpeting Clearance for servicing

Insulation Blankets . . . . . . . . . . . . . . . . . . . . . . . . . 17

Air Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Unconﬁ ned Space. . . . . . . . . . . . . . . . . . . . . . . . . . 17

Unusually Tight Construction . . . . . . . . . . . . . . . . . 17

Conﬁ ned Space. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Direct Vent Appliances . . . . . . . . . . . . . . . . . . . . . . 18

Exhaust Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Fresh Air Openings For Conﬁ ned Spaces. . . . . . . . 18

Chemical Vapor Corrosion . . . . . . . . . . . . . . . . . . . 19

INSTALLING THE NEW WATER HEATER 20

Water Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Space Heating And Potable Water Systems . . . . . . 20

Combo Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

System Requirements Installation

Closed Water Systems . . . . . . . . . . . . . . . . . . . . . . 22

Thermal Expansion . . . . . . . . . . . . . . . . . . . . . . . . . 22

Temperature-Pressure Relief Valve. . . . . . . . . . . . . 23

T&P valve discharge pipe requirements: Temperature-Pressure Relief Valve and

Pipe Insulation

High Altitude Installation . . . . . . . . . . . . . . . . . . . . . 24

Gas Piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Sediment Traps/Dirt Leg . . . . . . . . . . . . . . . . . . . . . 25

Filling The Water Heater . . . . . . . . . . . . . . . . . . . . . 26

Venting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Termination Clearances Sidewall Power Vent. . . . . 27

Blower Assembly Installation. . . . . . . . . . . . . . . . . . 28

Installation Of Vent System. . . . . . . . . . . . . . . . . . . 28

Planning The Vent System . . . . . . . . . . . . . . . . . . . 28

High Ambient Temperature Installations . . . . . . . . . 28

Polypropylene Vent Systems . . . . . . . . . . . . . . . . . 29

Condensate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Exhaust Venting . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Important Notes and Warnings Venting terminations and sizing Vent screen installation Calculating Equivalent Feet Venting instructions Vent pipe connection to blower Different coupling installations according to vent sizes

Blower Exhaust Direction . . . . . . . . . . . . . . . . . . . . 35

Vent Pipe Preparation . . . . . . . . . . . . . . . . . . . . . . . 35

Installation Checklist . . . . . . . . . . . . . . . . . . . . . . . . 38

LIGHTING INSTRUCTIONS 39 OPERATING THE TEMPERATURE CONTROL SYSTEM 40

Gas Control Valve/Thermostat . . . . . . . . . . . . . . . . 41

FOR YOUR INFORMATION 42

Start Up Conditions . . . . . . . . . . . . . . . . . . . . . . . . . 42

Condensate Thermal expansion Closed water systems Smoke/odor Strange sounds

Operational Conditions . . . . . . . . . . . . . . . . . . . . . . 42

Smelly water

“Air” In Hot-Water Faucets . . . . . . . . . . . . . . . . . . . 43

PERIODIC MAINTENANCE 44

General Upkeep . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Venting System Inspection . . . . . . . . . . . . . . . . . . . 44

Blower Maintenance . . . . . . . . . . . . . . . . . . . . . . . . 44

Cleaning The Blower. . . . . . . . . . . . . . . . . . . . . . . . 44

Burner Operation And Inspection . . . . . . . . . . . . . . 45

Combustion Chamber And Burner Cleaning. . . . . . 46

Housekeeping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Anode Rod Inspection. . . . . . . . . . . . . . . . . . . . . . . 46

Anode Rod . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Removing Anode Rod: Installing Anode Rod:

Temperature-Pressure Relief Valve Test . . . . . . . . . 47

Draining And Flushing. . . . . . . . . . . . . . . . . . . . . . . 48

To drain the water heater storage tank: To ﬂ ush the water heater storage tank: LEAKAGE CHECKPOINTS 49

Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

REFERENCE PARTS LISTING 50 TROUBLESHOOTING GUIDELINES 52

Resetting The Heater Control . . . . . . . . . . . . . . . . . 54

Lockouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Soft Lockout Hard Lockout

Ignition State And Timing . . . . . . . . . . . . . . . . . . . . 55

System Status And Error Codes . . . . . . . . . . . . . . . 55

LIMITED WARRANTY 58

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SAFE INSTALLATION, USE AND SERVICE

Your safety and the safety of others is extremely important in the installation, use and servicing of this water heater. Many safety-related messages and instructions have been provided in this manual and on your own water heater to warn you and others of a potential injury hazard. Read and obey all safety messages and instructions throughout this manual. It is very important

that the meaning of each safety message is understood by you and others who install, use or service this water heater.

This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.

DANGER indicates an imminently

DANGER

WARNING

CAUTION

hazardous situation which, if not avoided, will result in death or injury.

WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or injury.

CAUTION indicates a potentially hazardous situation which, if not avoided, could result in minor or moderate injury.

CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not avoided, could result in property damage

All safety messages will generally tell you about the type of hazard, what can happen if you do not follow the safety message and how to avoid the risk of injury.

The California Safe Drinking Water and Toxic Enforcement Act requires the Governor of California to publish a list of substances known to the State of California to cause cancer, birth defects or other reproductive harm and requires businesses to warn of potential exposure to such substances.

This product contains a chemical known to the State of California to cause cancer, birth defects or other reproductive harm. This appliance can cause low level exposure to some of the substances listed in the Act.

IMPORTANT DEFINITIONS

Qualiﬁ ed Installer: A qualiﬁ ed installer must have ability equivalent to a licensed tradesman in the ﬁ elds of plumbing, air supply, venting and gas supply, including a thorough understanding of the requirements of the National Fuel Gas Code as it relates to the installation of gas ﬁ red water heaters. The qualiﬁ ed installer must also be familiar with the design features and use of ﬂ ammable vapor ignition resistant water heaters and have a thorough understanding of this Installation and Operating manual.

Service Agency: A service agency also must have ability equivalent to a licensed tradesman in the ﬁ elds of plumbing, air supply, venting and gas supply, including a thorough understanding of the requirements of the National Fuel Gas Code as it relates to the installation of gas ﬁ red water heaters. The service agency must also have a thorough understanding of this Installation and Operating manual, and be able to perform repairs strictly in accordance with the service guidelines provided by the manufacturer.

Gas Supplier: The Natural Gas or Propane Utility or service who supplies gas for utilization by the gas burning appliances within this application. The gas supplier typically has responsibility for the inspection and code approval of gas piping up to and including the Natural Gas meter or Propane storage tank of a building. Many gas suppliers also offer service and inspection of appliances within the building.

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GENERAL SAFETY

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GENERAL SAFETY

WARNING

Breathing Hazard - Carbon Monoxide Gas

• Install vent system in accordance with codes.

• Do not operate water heater if flood damaged.

• For operation above 10,100’, a high altitude orifice must be installed.

• Do not operate if soot buildup is present.

• Do not obstruct water heater air intake with insulating jacket.

• Do not obstruct blower air intake.

• Do not place chemical vapor emitting products near water heater.

• Gas and carbon monoxide detectors are available.

• No vent damper installation is compatible with this power vented water heater.

Breathing carbon monoxide can cause brain damage or death.

Always read and understand instruction manual.

DANGER

FLAMMBLE

Vapors from flammable liquids may explode and catch fire causing death or severe burns.

Do not use or store flammable products such as gasoline, solvents or adhesives in the same room or area near the water heater.

Keep flammable products:

1. far away from heater,

2. in approved containers,

3. tightly closed and

4. out of children's reach.

Installation: Do not install the water heater where flammable products will be stored or used.

Flammable Vapors

Water heater has a main burner and hot surface igniter. The hot surface igniter:

1. can be triggered at any time and

2. the hot surface will ignite flammable vapors.

Vapors:

1. cannot be seen,

2. are heavier than air,

3. go a long way on the floor and

4. can be carried from other rooms to the the electodes by air currents.

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INTRODUCTION

Thank You for purchasing this water heater. Properly

installed and maintained, it should give you years of trouble free service.

Abbreviations found in this Installation and Operating manual:

• CSA - Canadian Standards Association

• ANSI - American National Standards Institute

• NFPA - National Fire Protection Association

• ASME - American Society of Mechanical Engineers

• UL - Underwriters Laboratories Inc.

• AHRI - Air Conditioning, Heating and Refrigeration

Institute.

This gas-ﬁ red water heater is design certiﬁ ed by CSA International, under Water Heater Standard ANSI

Z21.10.1 • CSA 4.1 (current edition).

QUALIFIED INSTALLER OR SERVICE AGENCY

Installation and service of this water heater requires ability equivalent to that of a Qualiﬁ ed Agency (as deﬁ ned by ANSI below) in the ﬁ eld involved. Installation skills such as plumbing, air supply, venting, gas supply and electrical supply are required in addition to electrical testing skills when performing service.

ANSI Z223.1 2006 Sec. 3.3.83: “Qualiﬁ ed Agency” - “Any individual, ﬁ rm, corporation or company that either in person or through a representative is engaged in and is responsible for (a) the installation, testing or replacement of gas piping or (b) the connection, installation, testing, repair or servicing of appliances and equipment; that is experienced in such work; that is familiar with all precautions required and that has complied with all the requirements of the authority having jurisdiction.”

If you are not qualiﬁ ed (as deﬁ ned by ANSI above) and licensed or certified as required by authority having jurisdiction to perform a given task, do not attempt to perform any of the procedures described in this manual. If you do not understand the instructions given in this manual do not attempt to perform any procedures outlined in this manual.

READ ENTIRE MANUAL BEFORE ATTEMPTING TO INSTALL OR OPERATE THE WATER HEATER.

2. The installation must conform with these instructions and local code authority having jurisdiction. In absence of local codes, installation must comply with current editions of the National Fuel Gas Code, ANSI Z223.1/ NFPA 54 and National Electrical Code, NFPA 70. All documents are available from:

CSA International, 8501 East Pleasant Valley Road, Cleveland, Ohio, United States 44131-5575.

NFPA documents are also available from: National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02269.

3. The water heater, when installed, must be electrically grounded in accordance with the local codes or in the absence of local codes: the National Electrical Code (NFPA 70).

4. If after reading this manual you have any questions or do not understand any portion of the instructions, call the local gas utility or the manufacturer whose name appears on the rating plate.

5. Carefully plan the place where you are going to put the water heater. Correct combustion, vent action, and vent pipe installation are very important in preventing death from possible carbon monoxide poisoning and ﬁ res (see Figure 14 & Figure 15). Examine the location to ensure the water heater complies with the “Locating the New Water Heater” section in this manual.

6. For installation in California, this water heater must be braced, anchored, or strapped to avoid falling or moving during an earthquake. See instructions for correct installation procedures. Instructions may be obtained from:

California Ofﬁ ce of the State Architect, 400 P Street, Sacramento, CA 95814.

PREPARING FOR THE INSTALLATION

1. Read the “General Safety Information” section of this manual ﬁ rst and then entire manual carefully. If you don’t follow safety rules, the water heater will not operate properly. It could cause DEATH, SERIOUS BODILY INJURY AND/OR PROPERTY DAMAGE. This manual contains instructions for installation, operation, and maintenance of the gas-ﬁ red water heater. It also contains warnings throughout the manual that you must read and be aware of. All warnings and instructions are essential to proper operation of the water heater and your safety. Since we cannot put everything on the ﬁ rst few pages,

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7. Massachusetts Code requires this water heater to be installed In accordance with Massachusetts 248-CMR

2.00: State Plumbing Code and 248-CMR 5.00.

8. Complies with California Health and Safety code 116875 (known as AB-1953) and with weighted average maximum of 0.25% lead.

INSTALLATION REQUIREMENTS FOR THE COMMONWEALTH OF MASSACHUSETTS

COMMONWEALTH OF MASSACHUSETTS For all side wall terminated, horizontally vented power vent, direct vent and power direct vent gas fueled water heaters installed in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above ﬁ nished grade in the area of the venting, including but not limited to decks and porches, the following requirements shall be satisﬁ ed:

INSTALLATION OF CARBON MONOXIDE DETECTORS At the time of installation of the side wall horizontal vented gas fueled equipment, the installing plumber or gasﬁ tter shall observe that a hard wired carbon monoxide detector with an alarm and battery back-up is installed on the ﬂ oor level where the gas equipment is to be installed. In addition, the installing plumber or gasﬁ tter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling, building or structure served by the sidewall horizontal vented gas fueled equipment. It shall be the responsibility of the property owner to secure the services of qualiﬁ ed licensed professionals for the installation of hard wired carbon monoxide detectors. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the hard wired carbon monoxide detector with alarm and battery back-up may be installed on the next adjacent ﬂ oor level. In the event that the requirements of this subdivision can not be met at the time of completion of installation, the owner shall have a period of thirty (30) days to comply with the above requirements provided that during said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall be installed. APPROVED CARBON MONOXIDE DETECTORS

Each carbon monoxide detector as required in accordance with the above provisions shall comply with NFPA 720 and be ANSI/ UL 2034 listed and CSA certiﬁ ed.

SIGNAGE A metal or plastic identiﬁ cation plate shall be permanently mounted to the exterior of the building at a minimum height of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled heating appliance or equipment. The sign shall read, in print size no less than one- half (1/2) inch in size, “GAS VENT DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS.”

INSPECTION The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance with the provisions of 248 CMR 5.08(2)(a) 1 through 4.

EXEMPTIONS The following equipment is exempt from 248 CMR 5.08(2) (a) 1 through 4:

1. The equipment listed in Chapter 10 entitled “Equipment Not Required To Be Vented” in the most current edition of NFPA 54 as adopted by the Board; and

2. Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate from the dwelling, building, or structure used in whole or in part for residential purposes.

MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM PROVIDED When the manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design or venting system components with the equipment, the instructions provided by the manufacturer for installation of the equipment and the venting system shall include:

1. Detailed instructions for the installation of the venting system design or the venting system components; and

2. A complete parts list for the venting system design or venting system.

MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED When the manufacturer of Product Approved side wall horizontally vented gas fueled equipment does not provide the parts for venting the ﬂ ue gases, but identiﬁ es “special venting systems,” the following requirements shall be satisﬁ ed by the manufacturer:

1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation instructions; and

2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a parts list and detailed installation instructions.

A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment, all venting instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain with the appliance or equipment at the completion of the installation.

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INSTALLATION GRAPHIC: GAS-FIRED POTABLE WATER HEATING/SPACE HEATING SYSTEM

• If your water heater will be installed in the Commonwealth of Massachusetts, refer to the following

graphic during installation and during modifications to the water supply system.

COMBINATION SPACE HEATING / POTABLE WATER HEATING SYSTEM

TEMPERED WATER TO FIXTURES (MUST MEET TEMPS LISTED IN MASS. CODE 248 CMR

MUST BE VERTICAL TO REMOVE A

MIXING VALVE (MUST BE INSTALLED BELOW TOP OF WATER HEATER AS PER MANUFACTURER’S RECOMMENDATIONS)

WATER HEATER ACCEPTED BY THE BOARD FOR INSTALLATION IN MASSACHUSETTS.

MASSACHUSETTS INSTALLATION REQUIREMENTS:

1.) CONNECT ELECTRONICALLY-CONTROLLED TIMER TO AN ALL-BRONZE PUMP. PUMP MUST ACTIVATE EVERY 6 HOURS

2.) ALL WATER PIPING MUST BE INSTALLED AND INSULATED IN ACCORDANCE WITH MASSACHUSETTS CODE (248 CMR

3.) PIPING LOOP BETWEEN WATER HEATER AND AIR HANDLER MUST BE INSTALLED IN COMPLIANCE WITH 248 CMR.

† REQUIRED FOR MASSACHUSETTS.

‡ PIPING FROM THE TOP OF THE WATER HEATER WITH TEES IS ACCEPTABLE.

IR BUBBLES

FOR 60 SECONDS. TURN PUMP TIMER OFF BEFORE CLOSING PIPING LOOP SHUT-OFF VALVE.

& 780 CMR).

†

)

†

TYPICAL MIXING VALVE INSTALLATION

EXPANSION TANK

CHECK

VALVE

UNION

HOT

WATER

OUT

VACUUM

†

RELIEF VALVE

UNION

TEMP/ PRESSURE RELIEF VALV E

SEE NOTE ‡

100’-0” MAXIMUM DISTANCE FROM WATER HEATER TO FAN COIL AND BACK. (DEVELOPED LENGTH) NOT INCLUDING COIL

CHECK VALVE

(1/8” HOLE

DRILLED IN CLAPPER)

PUMP

AIR

HANDLER

SHUT-OFF

VALV E

IN HEATING UNIT

COLD WATER INLET

†

FLOW CONTROL

OUT

COIL

AIR

HANDLER

†

SHUT-OFF

VALVE

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TYPICAL INSTALLATION

GET TO KNOW YOUR WATER HEATER - GAS MODELS (list referencing Figures 1-7)

1. Vent Termination Elbow with Rodent Screen

2. *Vent Pipe

3. *Vent Pipe Coupling (if required)

4. *Vent Pipe Elbow (long radius)

5. Blower High Limit Switch (see Figure 6)

6. T&P Valve

7. Cold-Water Inlet Nipple/Diptube

8. Bafﬂ e Assembly

9. * Discharge Pipe

10. Gas Control Valve/Thermostat (Honeywell)

11. Gas Valve Electronic Control Module And Cover (Honeywell)

12. Drain Valve

13. Outer Gas Door

14. Manifold Door Assembly (behind outer door) (see Figure 3 & Figure 4)

15. *Floor Drain

16. *Metal Drain Pan

17. Flammable Vapor Sensor (under cover) (see Figure 5)

18. **Combo Heating System Return Inlet (Optional)

19. Air Inlet Snorkel

20. **Combo Heating System Supply Outlet (Optional)

21. Blower with Power Cord (see also Figure 6)

22. Air Switch (inside box) (see Figure 6)

23. Junction Box (see Figure 6)

24. Junction Box Cover (see Figure 6)

25. Air Tubing (see Figure 6)

26. Rubber Coupling (see also Figure

27. Gear Clamp (see also Figure 6)

28. Flue Collector

29. Hot-Water Outlet Nipple

30. Anode (under cap)

31. ***Control Harness

32. Flexible Manifold Tube (see Figure 3 & Figure 4)

33. Viewport (see Figure 3 & Figure 4)

34. Flame Sensor Rod (see Figure 3 & Figure 4)

35. Gas Oriﬁ ce (see Figure 3 & Figure 4)

36. Sheet Metal Burner (see Figure 3 & Figure 4)

37. Gas Manifold (see Figure 3 & Figure 4)

38. Hot-Surface Igniter (see Figure 3 & Figure 4)

39. Manifold Door Gasket (see Figure 3 & Figure 4)

40. Manifold Door (see Figure 3 & Figure 4)

41. Two Piece Grommet With Clip (see Figure 3 & Figure 4)

42. *Inlet Water Shut-off Valve

43. *Gas Supply*

44. *Main Manual Gas Shut-off Valve

45. *Ground Joint Union (gas connection)

46. *Sediment Trap/Dirt Leg

47. *Union (water connection)

48. Rating Plate

49. *Thermal Expansion Tank (required for all closed systems)

*, **, ***, **** see notes on following

page

Blower

Dilution Air

Inlets

Combustion

Air Inlets

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Front View Rear View

Figure 1. Figure 2.

Natural gas and Propane main burner with igniter assembly for 40k to 50k Btu/hr models

Figure 3.

Natural gas and Propane main burner with igniter assembly for 60k to 75k Btu/hr models

4041

Vacuum relief valve install per local codes (not supplied with heater).

Figure 6.

32 34

Figure 4.

Figure 7.

Notes:

* Items not supplied with the water heater. ** The side recirculation loop connections may not be

used as the primary water inlet and outlet connections. See “Combo Heating Inlet And Outlet Side Taps”

below. *** Caution harness has 120 VAC In operation. **** See “Planning The Vent System”, “Condensate” and

“Blower Assembly Installation” for more information.

REPLACEMENT PARTS AND DELIMING PRODUCTS

Replacement parts and recommended delimer may be ordered through authorized servicers or distributors. When ordering parts, provide complete model and serial numbers (see rating plate), quantity and name of part desired. Standard hardware items may be purchased locally.

COMBO HEATING INLET AND OUTLET SIDE TAPS

Models equipped with Combo Heating capabilities are shipped with the two side plumbing taps OPEN (items 18 and 20 in Figure 1 and see also Figure 8 & Figure 25). If the heater is to be operated without using the side taps, these openings must be closed with the two pipe plugs supplied with the heaters.

Figure 5.

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WATER PIPING - MIXING VALVE USAGE

Mixing Valves

Water temperature over

DANGER

125°F can cause severe burns instantly resulting in severe injury or death.

his appliance has been design certiﬁ ed as complying with American National Standard/CSA Standard for water heaters and certain models with side plumbing connections are considered suitable for Water (Potable) Heating and Space Heating. Note: Do not use in space heating only applications.

Children, the elderly and the disabled and are at highest risk of scald injury.

Feel water before bathing or showering.

Temperature limiting devices

HOT

such as mixing must be installed when required by codes and to ensure safe

BURN

temperatures at fixtures.

Water heated to a temperature which satisﬁ es space heating, clothes washing, dish washing, and other sanitizing needs can scald and cause permanent injury upon contact. Short repeated heating cycles caused by small hot-water uses can cause a temperature increase of the hot water by 20F° higher than the heater’s temperature settings.

SUGGESTED PIPING ARRANGEMENT FOR

TOP CONNECTIONS

MIXING VALVE

TEMPERATUREPRESSURE RELIEF VALVE

* NOTE: THE

T&P VALVE

DISCHARGE

PIPE MUST

BE PIPED

DIRECTLY TO

THE DRAIN

OR EXTERNAL

TO THE

BUILDING

DISCHARGE PIPE (DO NOT CAP OR PLUG)

TEMPERED POTABLE WATER

HEATING. THE HOT AND COLD FITTING

SHUT-OFF

VALV E

COLD-WATER

INLET

CERTAIN

MODELS ARE EQUIPPED WITH SIDE PLUMBING

CONNECTIONS

FOR SPACE

ASSEMBLIES (PART #9001262)

CAN BE ORDERED

THROUGH THE

MANUFACTURER

METAL DRAIN

PAN 1.75”

MAX. DEPTH.

AT LEAST 2”

GREATER THAN

THE DIAMETER OF THE WATER

HEATER.

The water supply pressure should not exceed 80 psi. If this occurs, a pressure reducing valve with a bypass should be installed in the cold water inlet line. This should be placed on the supply to the entire house in order to maintain equal hot and cold water pressures.

SUGGESTED PIPING

ARRANGEMENT FOR

TOP CONNECTIONS

NON-TEMPERED

WATER SUPPLY

MIXING VALVE

MASSACHUSETTS: INSTALL A VACUUM RELIEF IN COLD WATER LINE PER SECTION 19 MGL

142.

GAS

SUPPLY

DRAIN VALV E

METAL DRAIN

PAN 1.75” MAX.

DEPTH. AT

LEAST

2” GREATER

THAN THE

DIAMETER OF

THE WATER

HEATER.

TEMPERED

POTABLE WATER

SHUT-OFF

VALV E

COLD-WATER

INLET

NON-TEMPERED

WATER RETURN

TEMPERATUREPRESSURE RELIEF VALVE

DISCHARGE PIPE (DO NOT CAP OR PLUG)

* NOTE: THE

T&P VALVE

DISCHARGE PIPE

MUST BE PIPED

DIRECTLY TO

THE DRAIN OR

EXTERNAL TO

THE BUILDING

6” MAX. AIR GAP*

Figure 9.

GAS SUPPLY

6” MAX. AIR GAP*

MASSACHUSETTS: INSTALL A VACUUM RELIEF IN COLD WATER LINE PER SECTION 19 MGL 142.

DRAIN VALV E

Figure 8.

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Some people are more likely to be permanently injured by hot water than others. These include the elderly, children, the inﬁ rm and the physically/mentally disabled. Table 1 (published by U.S. Government Memorandum,

1978) shows the approximate time-to-burn relationship for normal adult skin. If anyone using hot water provided by the water heater being installed ﬁ ts into one of these groups or if there is a local code or state law requiring a certain water temperature at the point of use, then special precautions must be taken.

Water

Temperature

°F

Time for 1st

Degree Burns

(Less Severe Burns)

110 (normal shower temp.)

116 (pain threshold)

116 35 minutes 45 minutes

122 1 minute 5 minutes

131 5 seconds 25 seconds

140 2 seconds 5 seconds

149 1 second 2 seconds

154 instantaneous 1 seconds

(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong, Sept. 15,1978)

Time for Permanent

Burns 2nd & 3rd

Degree (Most

Severe Burns)

Table 1.

In addition to using lowest possible temperature setting that satisﬁ es demand of application, a mixing valve should be installed at water heater (see Figure 8 & Figure 9) or at hot-water taps to further reduce system water temperature. Mixing valves are available at plumbing supply stores. Consult a Qualiﬁ ed Installer or Service Agency. Follow mixing valve manufacturer’s instructions for installation of the valves. Before changing the factory setting on the thermostat, read the “Operating The Temperature Control System” section in this manual.

WATER HEATER OPERATION

Figure 10 shows the water heater’s sequence of operation when a call for heat is initiated. The ignition control module will attempt to light the burner three times. If the ignition control does not detect ignition it will enter lockout mode and ﬂ ash the corresponding error code.

HEATER

THERMOSTAT

CALLS FOR

HEAT

HEATER CONTROL CHECKS TO ENSURE BLOWER PRESSURE

SWITCH IS OPEN

BLOWER IS

ENERGIZED

CONTROL CHECKS TO ENSURE PRES-

SURE SWITCH CLOSES

INDICATING BLOWER

IS OPERATING AND

THERE ARE NO

VENTING BLOCKAGES

(INLET OR OUTLET)

IGNITER IS ENERGIZED

AND MAIN GAS VALVE

IS OPENED

MAIN BURNER COMES ON AND THE FLAME IS SENSED BY CONTROL

MAIN BURNER CONTIN-

UES TILL THE WATER IN THE TANK REACHES THERMOSTAT SETTING

MAIN BURNER SHUTS

OFF. BLOWER

CONTINUES FOR A

POST PURGE TIME

HEATER

REMAINS ON STANDBY UNTIL NEXT CALL FOR

HEAT

Figure 10.

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ELECTRICAL REQUIREMENTS & WIRING DIAGRAM

WARNING

Electric Shock Hazard

Disconnect power before servicing.

Replace all parts and panels before operating.

Failure to do so can result in death or electrical shock.

Before plugging in the water heater, always make sure:

• The voltage and frequency correspond to that

speciﬁ ed on the water heater wiring diagram.

• The electrical outlet has the proper overload fuse or

breaker protection.

1. The unit must be connected to a dedicated power supply.

2. The unit must be connected to a 120VAC power supply.

3. The water heater must be properly grounded.

4. This water heater is a polarity sensitive appliance and will not operate if the power supply polarity is reversed.

Note: Always reference the wiring diagram for the correct electrical connections.

LABEL ALL WIRES PRIOR TO DISCONNECTION WHEN SERVICING CONTROLS. WIRING ERRORS CAN CAUSE IMPROPER AND DANGEROUS OPERATION. VERIFY PROPER OPERATION AFTER SERVICING. POWER VENT WIRING SCHEMATIC.

NOTE: REFER TO THE “INSTALLATION CHECKLIST” BEFORE OPERATING THIS HEATER.

EARTH GND

CAPACITOR

BLOWER

FLAME SENSOR

HOT SURFACE IGNITER

PRESSURE SWITCH

HIGH LIMIT SWITCH

FLAMMABLE VAPOUR SENSOR

After making all electrical connections, completely ﬁ ll the tank with water and check all connections for leaks. Open the nearest hot-water faucet and let it run for 3 minutes to purge the water lines of air and sediment and to ensure complete ﬁ lling of the tank. The electrical power may then be turned on. Verify proper operation after servicing. See also “Installation Checklist”. CAUTION

Circled numbers indicate sequence of operation.

Figure 11.

Figure 12.

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SAFETY LOCKOUTS

This water heater has several lockout features designed to prevent the heater from operating in unsafe conditions.

HIGH LIMIT CONTROLS (Energy Cut Off)

Thermostat/Water Temperature

This feature is a part of the gas control valve/thermostat (see Figure 1, item 10) and limits the maximum water temperature. In the event of the water overheating, this safety feature shuts off the fuel supply to the burner.

Blower High Limit Switch

This device is located on the blower (see Figure 6, item

5) and limits the maximum temperature of the blower. If the blower temperature rises above the temperature setting, the switch opens causing the heater to shut down. The switch will auto reset once the temperature drops sufﬁ ciently.

BLOWER AIR PRESSURE SWITCH

This device, located in the junction box, monitors the air pressure produced by the blower. In the event that the exhaust venting becomes blocked or sufﬁ ciently restricted, the switch will shut the heater down (see Figure 6, item 22).

If there is a problem with the wiring of the ﬂ ammable vapor sensor or the ﬂ ammable vapor interface, the LED will ﬂ ash the failure status code (see “System Status And Error Codes”).

* ROTATE LEFT (CCW) TO REMOVE

COVER*

MOUNTING

BRACKET

FLAMMABLE

VAPOR SENSOR

(PULL TO REMOVE)

Figure 13.

FLAMMABLE VAPOR SENSOR

When using a gas ﬁ red water heater there is a risk of ﬂ ammable vapors entering the combustion chamber, being

ignited by the burner ﬂ ame and causing a ﬂ ashback. In order to detect such ﬂ ammable vapors before they enter the combustion chamber, this water heater is equipped with a ﬂ ammable vapor sensor (FVS). It is a chemical- absorption based sensor that is connected to the gas control/thermostat (see Figure 13). When exposed to

ﬂ ammable vapors it will trigger the control to stop the ﬂ ow of gas and enter the FVS lockout state. While in the

FVS lockout state the LED on the control will ﬂ ash the gas lockout code. (Refer to the “System Status And Error Codes” section of this manual for an explanation of the codes applicable to the control installed on your water heater.) If this error occurs, check around the water heater for sources of chemical contamination such as: ﬂ ammable vapors including gas vapors, solvents, paint and thinners as well as sources of water and detergents.

Note: Resetting the heater will reset the FVIR circuit if all sources of contamination have been removed and the sensor clears. If all sources of contamination have been removed and the system will not reset, the sensor will need to be replaced (see “Resetting the Heater Control”).

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LOCATING THE NEW WATER HEATER

FACTS TO CONSIDER ABOUT THE LOCATION

Carefully choose an indoor location for the new water heater because the placement is a very important consideration for the safety of the occupants in the building and for the most economical use of the appliance. This water heater is not for use in manufactured (mobile) homes or outdoor installation. Whether replacing an old water heater or putting the water heater in a new location, the following critical points must be observed:

1. Select a location indoors as close as practical to the vent termination or location to which the water heater vent piping is going to be connected, and as centralized with the water piping system as possible.

2. Selected location must provide adequate clearances for servicing and proper operation of the water heater.

3. Ensure the area has a continuous supply of air for combustion, dilution and ventilation.

4. Avoid locations that could cause the water heater to freeze from outside air.

5. Selected location must provide access to a properly grounded electrical branch circuit. A dedicated circuit is preferred. Do not use a GFI outlet.

6. Avoid locations that expose the water heater to direct sunlight.

7. Keep combustibles such as boxes, magazines, clothes, etc., away from the water heater area.

Important: Do not use an extension cord to connect the water heater to an electrical outlet. Important: this heater has special venting requirements when installed in areas where the ambient temperatures exceed 110°F (see “High Ambient Temperature Installations”).

CAUTION

Property Damage Hazard

• All water heaters eventually leak.

• Do not install without adequate drainage.

Installation of the water heater must be accomplished in such a manner that if the tank or any connections should leak, the ﬂ ow 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 ﬂ oor. In all cases, a metal drain pan should be installed under the water heater. Metal drain pans are available at your local hardware store. Such a metal drain pan must have a clearance of at least 1” greater than any point on the water heater’s outer jacket and must be piped to an adequate drain. The pan must have a maximum depth of 1.75”. Water heater life depends upon water quality, water pressure and the environment in which the water heater is installed. Water heaters are sometimes installed in locations where leakage may result in property damage, even with the use of a metal drain pan piped to a drain. However, unanticipated damage can be reduced or

prevented by a leak detector or water shut-off device used in conjunction with a piped metal drain pan. These devices are available from some plumbing supply wholesalers and retailers, and detect and react to leakage in various ways:

• Sensors mounted in the metal drain pan that trigger an

alarm or turn off the incoming water to the water heater when leakage is detected.

• Sensors mounted in the metal drain pan that turn off

the water supply to the entire building when water is detected in the metal drain pan.

• Water supply shut-off devices that activate based on

the water pressure differential between the cold-water and hot-water pipes connected to the water heater.

• Devices that will turn off the gas supply to a gas water

heater while at the same time shutting off its water supply.

STORAGE OF FLAMMABLE LIQUIDS

Flammable liquids (such as gasoline, solvents, propane (LP or butane, etc.) and other substances (such as adhesives, paints, etc.) emit ﬂ ammable vapors which can be ignited by a gas water heater’s hot surface igniter (HSI) or main burner. The resulting ﬂ ashback and ﬁ re can cause death or serious burns to anyone in the area.

This water heater is equipped with a FV (Flammable Vapor) sensor for detecting the presence of ﬂ ammable vapors. When the sensor detects those vapors, the unit will shut down and not operate. Should this happen, please refer to the “Troubleshooting Guidelines” section of this manual. Even though this water heater is a ﬂ ammable vapors ignition resistant (FVIR) water heater and is designed to reduce the chances of ﬂ ammable vapors being ignited, gasoline and other ﬂ ammable substances should never be stored or used in the same vicinity or area containing a gas water heater or other open ﬂ ame or spark producing appliance. Examples of such locations are garages, storage and utility areas.

The water heater must be located and/or protected so it is not subject to physical damage by a moving vehicle.

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WARNING

Fire or Explosion Hazard

• Do not store or use gasoline or other flammable vapors and

liquids in the vicinity of this or any other appliance.

• Avoid all ignition sources if you smell gas.

• Do not expose water heater control to excessive gas

pressure.

• Use only gas shown on rating plate.

• Maintain required clearances to combustibles.

• Keep ignition sources away from faucets after extended

period of non-use.

Read instruction manual before

installing, using or servicing

water heater.

Clearance for servicing

Adequate clearance of 24” for servicing this appliance should be considered before installation, such as changing the anodes, etc.

A minimum clearance of 5.5” must be allowed for access to replaceable parts such as thermostats, drain valve and relief valve. When installing the heater, consideration must be given to proper location. Location selected should be as close to the wall as practicable and as centralized with the water piping system as possible.

TOP VIEW

OF CLOSET

WITHOUT DOOR

AIR INTAKE*

TOP VIEW OF CLOSET WITH

DOOR

WARNING

FLAMMABLES

FIRE AND EXPLOSION HAZARD

Can result in serious injury or death

Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. Storage or use of gasoline or other flammable vapors or liquids in the vicinity of this or any other appliance can result in serious injury or death.

Flammable Vapors

WARNING

Fire Hazard

For continued protection against risk of fire:

• Do not install water heater on carpeted floor.

• Do not operate water heater if flood damaged.

Clearances to combustibles

Minimum clearances between water heater and combustibles are 0” at the sides and rear, 5.5” from the front and 12” from top (standard clearance.) If clearances stated on the heater differ from standard clearances, install water heater according to clearances stated on the heater (see Figure 14).

0” MIN. 0” MIN.

0” MIN.

* DO NOT BLOCK THE AIR INTAKES AT THE BACK OF THE WATER HEATER.

5.5” MIN.

Figure 14.

A gas water heater cannot operate properly without the correct amount of air for combustion and ventilation. Do not install in a conﬁ ned area such as a closet unless you provide air as shown below and described in the “Air Requirements” section (see Figure 15). Never obstruct the ﬂ ow of ventilation air for dilution and combustion. If you have any doubts or questions at all, call your gas supplier. Failure to provide the proper amount of combustion air can result in a ﬁ re or explosion and cause death, serious bodily injury, or property damage.

WARNING

Breathing Hazard - Carbon Monoxide Gas

• Install water heater in accordance with the instruction manual and NFPA54.

• To avoid injury, combustion and ventilation air must be taken from outdoors.

• Do not place chemical vapor emitting products near water heater.

Breathing carbon monoxide can cause brain damage or death.

Always read and understand instruction manual.

Floors with carpeting

This water heater must not be installed directly on carpeting. Carpeting must be protected by a metal or wood panel beneath the appliance extending beyond the full width and depth of the appliance by at least 3” in every direction, or if the appliance is installed in an alcove or closet, the entire ﬂ oor must be covered by the panel. Failure to heed this warning may result in a ﬁ re hazard.

Figure 15.

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If this water heater will be used in beauty shops, barber shops, cleaning establishments, or self-service laundries with dry cleaning equipment, it is imperative that the water heater or water heaters be installed so that combustion and ventilation air be taken from outside these areas. Propellants of aerosol sprays and volatile compounds, (cleaners, chlorine based chemicals, refrigerants, etc.) in addition to being highly ﬂ ammable in many cases, will also react to form corrosive hydrochloric acid when exposed to the combustion products of the water heater. The results can be hazardous, and also cause product failure.

INSULATION BLANKETS

Insulation blankets are available to the general public for external use on gas water heaters but are not necessary with these products. The purpose of an insulation blanket is to reduce standby heat loss encountered with storage tank heaters. Your water heater meets or exceeds the current standards with respect to insulation and standby loss requirements, making an insulation blanket unnecessary. Should you choose to apply an insulation blanket to this heater, you should follow these instructions (For identiﬁ cation of components mentioned below, see Figure 1 thru Figure 7). Failure to follow these instructions will restrict the air ﬂ ow required for proper combustion and dilution, potentially resulting in ﬁ re, asphyxiation, serious personal injury or death.

AIR REQUIREMENTS

For safe operation an adequate supply of fresh, uncontaminated air for combustion, dilution and ventilation must be provided. Note: Contaminated or dusty air may cause build-up on the blower wheel resulting in nuisance shut downs.

An insufﬁ cient supply of air can cause recirculation of combustion products resulting in contamination that may be hazardous to life. Such a condition often will result in a yellow, luminous burner ﬂ ame, causing sooting of the combustion chamber, burners and ﬂ ue tubes and creates a risk of asphyxiation.

Do not install the water heater in a conﬁ ned space unless an adequate supply of air for combustion, dilution and ventilation is brought into that space using the methods described in the “Conﬁ ned Space” section that follows.

Never obstruct the ﬂ ow of dilution/ventilation air. If you have any doubts or questions at all, call your gas supplier. Failure to provide the proper amounts of air can result in a ﬁ re or explosion and cause property damage, serious bodily injury or death. The combustion and dilution air inlets are shown in Figure 2. Important: Power Vented water heaters require air for combustion and dilution air for the blower.

• Do not apply insulation to the top of the water heater,

as this will interfere with safe operation of the blower assembly.

• Do not cover the outer door, thermostat or T&P relief

valve, FV sensor, or Air Intake Snorkel.

• Do not cover the “Installation And Operating manual”.

Keep it on the side of the water heater or nearby for future reference.

• Do obtain new warning and instruction labels from the

manufacturer for placement on the blanket directly over the existing labels.

• Do inspect the insulation blanket frequently to make

certain it does not sag, thereby obstructing combustion air ﬂ ow.

WARNING

Breathing Hazard - Carbon Monoxide Gas

• Do not obstruct water heater air intake(s) with insulating jacket.

• Gas and carbcn monoxide detectors are available.

• Install water heater in accordance with the instruction manual and NFPA54.

Breathing carbon monoxide can cause brain damage or death.

Always read and understand instruction manual.

UNCONFINED SPACE

An Unconﬁ ned Space is one whose volume is not less than 50 cubic feet per 1,000 Btu/hr of the total input rating of all appliances installed in the space. Rooms communicating directly with the space in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconﬁ ned space.

Makeup air requirements for the operation of exhaust fans, kitchen ventilation systems, clothes dryers and ﬁ replaces should also be considered in determining the adequacy of a space to provide combustion, ventilation and dilution air.

UNUSUALLY TIGHT CONSTRUCTION

In unconﬁ ned spaces in buildings, inﬁ ltration may be adequate to provide air for combustion, ventilation and dilution of ﬂ ue gases. However, in buildings of unusually tight construction (e.g., weather stripping, heavily insulated, caulked, vapor barrier, etc.) additional air must be provided using the methods described in the “Conﬁ ned Space” section that follows.

CONFINED SPACE

A Conﬁ ned Space is one whose volume is less than 50 cubic feet per 1,000 Btu/hr of the total input rating of all appliances installed in the space. Openings must be installed to provide fresh air for combustion, ventilation and dilution in conﬁ ned spaces. The required size for the openings is dependent on the method used to provide fresh air to the conﬁ ned space

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and the total Btu/hr input rating of all appliances installed in the space.

DIRECT VENT APPLIANCES

Other appliances installed in a Direct Vent conﬁ guration that derive all air for combustion from the outdoor atmosphere through sealed intake air piping are not factored in the total appliance input Btu/hr calculations used to determine the size of openings providing fresh air into conﬁ ned spaces.

EXHAUST FANS

Where exhaust fans are installed, additional air should be provided to replace the exhausted air. When an exhaust fan is installed in the same space with a water heater, sufﬁ cient openings to provide fresh air must be provided that accommodate the requirements for all appliances in the room and the exhaust fan. Undersized openings will cause air to be drawn into the room through the water heater’s vent system causing poor combustion. Sooting, serious damage to the water heater and the risk of ﬁ re or explosion may result. It can also create a risk of asphyxiation.

FRESH AIR OPENINGS FOR CONFINED SPACES

The following instructions should be used to calculate the size, number and placement of openings providing fresh air for combustion, ventilation and dilution in conﬁ ned spaces. The illustrations shown in this section of the manual are a reference for the openings that provide fresh air into conﬁ ned spaces only. Do not refer to these illustrations for the purpose of vent installation. See “Installation of Vent System” section for complete venting installation instructions.

Figure 16.

B. ALL AIR FROM OUTDOORS: (See Figure 17 thru

Figure 19)

The confined space shall be provided with two

permanent openings, one commencing within 12” of the top and one commencing within 12“ from the bottom of the enclosure. The openings shall communicate directly, or by ducts, with the outdoors or spaces (crawl or attic) that freely communicate with the outdoors.

1. When directly communicating with the outdoors, each opening shall have a minimum free area of 1 square inch per 4,000 Btu/hr of total input rating of all equipment in the enclosure (see Figure 17).

Chemical vapor corrosion of the ﬂ ue, blower assembly and vent system may occur if the air supply contains certain chemical vapors. Spray can propellants, cleaning solvents, refrigerator and air conditioner refrigerants, swimming pool chemicals, calcium and sodium chloride (water softener salt), waxes, bleach and process chemicals are typical compounds which are potentially corrosive.

A. ALL AIR FROM INSIDE BUILDINGS: (See Figure 16) The confined space shall be provided with two

permanent openings communicating directly with an additional room(s) of sufﬁ cient volume so that the combined volume of all spaces meets the criteria for an unconﬁ ned space. The total input of all gas utilization equipment installed in the combined space shall be considered in making this determination. Each opening shall have a minimum free area of one square inch per 1,000 Btu/hr of the total input rating of all gas utilization equipment in the conﬁ ned space, but not less than 100 square inches. One opening shall commence within 12” of the top and one commencing within 12” of the bottom of the enclosures.

Figure 17.

2. When communicating with the outdoors through vertical ducts, each opening shall have a minimum free area of 1 square inch per 4,000 Btu/hr of total input rating of all equipment in the enclosure (see Figure 18).

3. When communicating with the outdoors through horizontal ducts, each opening shall have a minimum free area of 1 square inch per 2,000 Btu/hr of total input rating of all equipment in the enclosure (see Figure 19).

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