A.O. Smith XWH-1000, XWH-1300, XWH-1700, XWH-2000, XWH-2600 Installation Manual

...

Instruction Manual

COMMERCIAL GAS WATER HEATERS

MODELS: XWH 1000, 1300, 1700 2000, 2600, 3400

SERIES 100/101

25589 Highway 1

McBee, SC 29101

WARNING: If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury or death.

MAINTENANCE - LIMITED WARRANTY

INSTALLATION - OPERATION -

Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.

WHAT TO DO IF YOU SMELL GAS:

Do not try to light any appliance.

•

Do not touch any electrical switch; do

•

not use any phone in your building.

Immediately call your gas supplier

•

from a neighbor’s phone. Follow the gas supplier’s instructions.

If you cannot reach your gas supplier,

•

call the fire department.

Installation and service must be performed by a qualified installer, service agency or the gas supplier.

Thank you for buying this energy efcient water heater. We appreciate your condence in our products.

PRINTED IN THE U.S.A. 0513 322433-002

TABLE OF CONTENTS ..........................................................................2

SAFE INSTALLATION, USE AND SERVICE.......................................... 3

GENERAL SAFETY................................................................................ 4

INTRODUCTION .................................................................................... 5

Model Identication ............................................................................ 5

Abbreviations Used ........................................................................... 5

Qualications ..................................................................................... 5

DIMENSIONS AND CAPACITY DATA .................................................... 6

FEATURES AND COMPONENTS ....................................................... 10

Component Description ................................................................... 12

CONTROL COMPONENTS ................................................................. 13

INSTALLATION CONSIDERATIONS ................................................... 15

GENERAL REQUIREMENTS .............................................................. 20

Location ........................................................................................... 20

Fresh Air Openings For Conned Spaces ....................................... 22

VENTING .............................................................................................. 24

Venting Supports ............................................................................. 27

CONDENSATE DISPOSAL .................................................................. 37

GAS SUPPLY CONNECTIONS ........................................................... 38

START UP AND OPERATIONS ........................................................... 40

LIGHTING AND OPERATING INSTRUCTIONS .................................. 42

CONTROL SYSTEM ............................................................................ 45

Burner Control System .................................................................... 45

Burner Control Operation ................................................................ 46

General Operational Sequence ....................................................... 47

Local Operator Interface: Display System ....................................... 49

Installation Instructions (S7999D OI Display) .................................. 49

Starting Up The S7999D OI Display ................................................ 50

Page Navigation .............................................................................. 50

TROUBLESHOOTING ......................................................................... 60

MAINTENANCE PROCEDURES ......................................................... 75

Maintenance Schedules .................................................................. 75

General Maintenance ...................................................................... 75

Burner Maintenance ........................................................................ 76

Venting Maintenance ....................................................................... 77

Heat exchanger Maintenance .......................................................... 77

Handling Ceramic Fiber Materials ................................................... 78

Replacement Parts .......................................................................... 78

PIPING DIAGRAMS ............................................................................. 79

NOTES ................................................................................................. 81

NOTES ................................................................................................. 82

LIMITED WARRANTY .......................................................................... 83

SAFE INSTALLATION, USE AND SERVICE

The proper installation, use and servicing of this water heater is extremely important to your safety and the safety of others.

Many safety-related messages and instructions have been provided in this manual and on your 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 injury or death.

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

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

CAUTION used without the safety alert

CAUTION

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 water heater can cause low level exposure to some of the substances listed in the Act.

symbol indicates a potentially hazardous situation which, if not avoided, could result in property damage.

IMPORTANT DEFINITIONS

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.

APPROVALS

GENERAL SAFETY

GROUNDING INSTRUCTIONS

This water heater must be grounded in accordance with the National Electrical Code, Canadian Electrical Code and/or local codes. Water heater is polarity sensitive; correct wiring is imperative for proper operation.

This water heater must be connected to a grounded metal, permanent wiring system, or an equipment grounding conductor must be run with the circuit conductors and connected to the equipment grounding terminal or lead on the water heater.

INLET WATER CONSIDERATIONS

Circulating water through the water heater and to the remote storage tank is accomplished by a pump.

CORRECT GAS

Make sure the gas on which the water heater will operate is the same as that speci ed on the water heater rating plate. Do not install the water heater if equipped for a different type of gas; con sult your supplier.

PRECAUTIONS

If the unit is exposed to the following, do not operate until all corrective steps have been made by a qualied service agent:

1. Exposure to re.

2. If damaged.

3. Firing without water.

4. Sooting.

If the water heater has been exposed to ooding, it must be replaced.

LIQUEFIED PETROLEUM GAS MODELS

Water heaters for propane or liqueed petroleum gas (LPG) are different from natural gas models. A natural gas water heater will not function safely on LP gas and no attempt should be made to convert a water heater from natural gas to LP gas.

HIGH ALTITUDE INSTALLATIONS

Rated inputs are suitable up to 2000 feet (610 m) elevation for Propane and 10,100 feet (3079 m) for Natural gas. Consult the factory for Propane installation at altitudes over 2000 feet (610 m).

FIELD INSTALLED COMPONENTS

When installing the water heater, the follow ing compo nents must be installed:

• Circulating Pump

• Remote Temperature Tank Sensor (Supplied with water heater)

• Storage Tank (Temperature & Pressure Relief Valve)

LP gas must be used with great caution. It is highly explosive and heavier than air. It collects rst in the low areas making its odor difcult to detect at nose level. If LP gas is present or even suspected, do not attempt to nd the cause yourself. Leave the building, leaving doors open to ventilate, then call your gas supplier or service agent. Keep area clear until a service call has been made.

At times you may not be able to smell an LP gas leak. One cause is odor fade, which is a loss of the chemical odorant that gives LP gas its distinctive smell. Another cause can be your physical condition, such as having a cold or diminishing sense of smell with age. For these reasons, the use of a propane gas detector is recommended.

If you experience an out of gas situation, do not try to relight appliances yourself. Call your local service agent. Only trained LP professionals should conduct the required safety checks in accordance with industry standards.

INTRODUCTION

This Instruction Manual covers models XWH 1000, 1300, 1700, 2000, 2600, 3400 - Series 100/101. The instructions and illustrations contained in this Instruction manual will provide you with troubleshooting procedures to diagnose and repair common problems and verify proper operation.

MODEL IDENTIFICATION

Check the rating plate afxed to the water heater. The following information describes the model number structure:

SERIES-100/101 DESIGNATION:

• XP = Extreme Performance

MODEL (APPLICATION):

• XWH = Automatic Circulating Water Heater

SIZE:

• 1000 = 920,000 Btu/hr input

• 1300 = 1,300,000 Btu/hr input

• 1700 = 1,700,000 Btu/hr input

• 2000 = 1,999,900 Btu/hr input

• 2600 = 2,600,000 Btu/hr input

• 3400 = 3,400,000 Btu/hr input

FUEL:

N = Natural gas P = Propane

ABBREVIATIONS USED

Abbreviations found in this Instruction Manual include :

• ANSI - American National Standards Institute

• ASME - American Society of Mechanical Engineers

• NEC - National Electrical Code

• NFPA - National Fire Protection Association

• UL - Underwriters Laboratory

• CSA - Canadian Standards Association

• AHRI - Air-Conditioning, Heating and Refrigeration Institute

QUALIFICATIONS

QUALIFIED INSTALLER OR SERVICE AGENCY

Installation and service of this water heater requires ability equivalent to that of a Qualied Agency, as dened by ANSI below. In the 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 Z21.13 - CSA 4.9: “Qualied Agency” - “Any individual, 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 qualied (as dened by ANSI above) and licensed or certied as required by the 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.

This product requires a formal Start-Up by an authorized service/ start-up provider that has been approved by the manufacturer for this specic product. Call 1-800-527-1953 to locate the nearest authorized start-up provider and arrange a factory start-up. Please provide as much notice as possible, preferably 2 weeks. Please have the model and serial number ready when you call. This start-up is required to activate the warranty and ensure safe, efcient operation.

Warranty on this product is limited and could be void in the event the unit is not installed per the instructions in this manual and/or not started up by an authorized factory trained service/start-up provider.

DIMENSIONS AND CAPACITY DATA

L B

AIR INTAKE

FLUE OUTLET

55 1/2"

7 7/8"

31 3/8"

FIGURE 1. SINGLE HEAT EXCHANGER WATER HEATER

TABLE 1. ROUGH IN DIMENSIONS (SINGLE)

Models XB-1000 XB-1300 XB-1700

Dimensions inches mm inches mm inches mm

Flue Outlet Diameter 6 152 8 152 8 203

Air Intake Diameter 6 152 6 152 8 203

Water Inlet 2 inch NPT 2 1/2 inch NPT

Water Outlet 2 inch NPT 2 1/2 inch NPT

Gas Inlet 2 inch NPT 2 inch NPT

A 47 1199 49 1245 57 1448

B 67 1702 68 1727 76 1930

C 29 737 29 737 29 737

D 37 940 38 965 37 940

E 23 584 23 584 24 610

F 9 229 9 229 9 229

G 34 864 34 864 34 864

H 44 111 8 45 1143 45 1143 J 6 152 6 152 6 152

K 11 279 11 279 11 279

L 12 305 11 279 12 305

TABLE 2. OPERATING CHARACTERISTICS

Models

(XB)

Type of Gas Inches W.C. kPa Inches W.C. kPa Inches W.C. kPa

Manifold Pressure Maximum Supply Pressure Minimum Supply Pressure

Min Fire -0.2 to - 0.3 -0.05 to - 0.07

1000, 1300, 1700 2000, 2600, 3400

Natural

Max Fire -3.0 to -3.9 -0.75 to -0.97

Min Fire -0.1 to - 0.3 -0.025 to -0.07

Propane

14.0 3.49 4.0 1.0

Max Fire -3.6 to -4.9 -0.90 to -1.22

FLUE OUTLET

AIR INTAKE

34 1/4"

31 7/8"

7 7/8"

55 7/8"

66 1/8"

10"

31 3/8"

FIGURE 2. DOUBLE HEAT EXCHANGER WATER HEATER

TABLE 3. ROUGH IN DIMENSIONS (DOUBLE)

Models XB-2000 XB-2600 XB-3400

Dimensions inches mm inches mm inches mm

Flue Outlet Diameter 8 203 8 203 10 254

Air Intake Diameter 8 203 8 203 10 254

Water Inlet 3 inch NPT 4 inch NPT

Water Outlet 3 inch NPT 4 inch NPT

Gas Inlet 2 inch NPT 3 inch NPT

A 47 1194 49 1245 57 1448

B 78 1981 80 2032 91 2311

C 36 914 37 940 37 940

D 22 559 22 559 22 559

E 40 1016 41 1041 41 1041

F 7 178 6 152 6 152

G 10 254 10 254 10 254

H 4 102 4 102 4 102

J 20 508 19 483 19 483

K 12 305 12 305 13 330

TABLE 4. RECOVERY CAPACITIES

86 1/4"

26 3/4"

Models

(XWH)

Input

Rating

(Btu/hr)

1000 920,000

1300 1,300,000

1700 1,700,000

2000 1,999,900

2600 2,600,000

3400 3,400,000

Temperature Rise - ΔT °F (°C)

Water

Flow

(22)

(33)

(39)

(44)

(50)

100

(56)

120

(67)

140

(78)

GPH 2,662 1,775 1,521 1,331 1,183 1,065 887 761

LPH 10,078 6,719 5,759 5,039 4,479 4,031 3,359 2,880

GPH 3,742 2,495 2,139 1,871 1,663 1,497 1,247 1,069

LPH 14,167 9,444 8,095 7,083 6,296 5,667 4,722 4,048

GPH 4,904 3,269 2,802 2,452 2,180 1,962 1,635 1,401

LPH 18,565 12,376 10,608 9,282 8,251 7,426 6,188 5,304

GPH 5,794 3,862 3,311 2,897 2,575 2,317 1,931 1,655

LPH 21,931 14,621 12,532 10,966 9,747 8,773 7,310 6,266

GPH 7,501 5,000 4,286 3,750 3,334 3,000 2,500 2,143

LPH 28,393 18,929 16,225 14,196 12,619 11,357 9,464 8,112

GPH 9,891 6,594 5,652 4,945 4,396 3,956 3,297 2,826

LPH 37,441 24,961 21,395 18,721 16,641 14,976 12,480 10,697

ELECTRICAL REQUIREMENTS

TABLE 5. ELECTRICAL REQUIREMENTS

MODELS

(XWH)

1000 120 60 30 A dedicated, single phase, 30 amp circuit breaker with

1300 120 60 30

1700 120 60 30

2000 120 60 60 A dedicated, single phase, 60 amp circuit breaker with

2600 120 60 60

3400 120 60 60

SUPPLY VOLTAGE

(VOLTS)

FREQUENCY

(HZ)

CURRENT

(AMPS)

ELECTRICAL NOTES

a grounded neutral should be provided to supply power to the water heater.

Models

(XWH)

1000 920,000

1300 1,300,000

1700 1,700,000

2000 1,999,900

2600 2,600,000

3400 3,400,000

Input

(Btu/hr)

FLOW, HEAD AND TEMPERATURE RISE

TABLE 6. FLOW, HEAD AND TEMPERATURE RISE

Temperature Rise - ΔT °F Flow Rate

Water Flow

20 30 40 Maximum Minimum

GPM 86 56 43 86 43

LPM 325 211 162 325 162

ΔP FT 26 12 7 26 7

ΔP M 7.9 3.7 2.1 7.9 2.1

GPM 120 80 60 120 60

LPM 453 302 226 453 226

ΔP FT 32.5 15 8 32.5 8

ΔP M 9.9 4.6 2.4 9.9 2.4

GPM 156 104 78 156 78

LPM 592 395 296 592 296

ΔP FT 35 14 8 35 8

ΔP M 10.7 4.3 2.4 10.7 2.4

GPM 184 123 92 184 92

LPM 696 464 348 696 348

ΔP FT 26 12 7 26 7

ΔP M 7.9 3.7 2.1 7.9 2.1

GPM 239 159 120 239 120

LPM 905 604 453 905 453

ΔP FT 32.5 15 8 32.5 8

ΔP M 9.9 4.6 2.4 9.9 2.4

GPM 313 209 156 313 156

LPM 1184 789 592 1184 592

ΔP FT 35 14 8 35 8

ΔP M 10.7 4.3 2.4 10.7 2.4

NOTE: Head Loss shown is through the water heater only and allows for no additional piping.

FEATURES AND COMPONENTS

3627

FIGURE 3. SINGLE HEAT EXCHANGER WATER HEATER COMPONENTS

1913

FIGURE 4. DOUBLE HEAT EXCHANGER WATER HEATER COMPONENTS

COMPONENT DESCRIPTION

1. Front access door: Provides access to the gas train, burner controllers and the heat exchanger.

2. Air Filter Box: Allows for the connection of the PVC air intake pipe to the water heater through a standard PVC adapter. It uses a lter mounted inside the box to prevent dust and debris from entering the water

heater.

3. Automatic air vents:

Designed to remove trapped air from the heat exchanger coils.

4. Blowers: The blowers pull in air and gas through the venturis. Air and gas mix inside the venturi and are pushed into the burners, where they burn inside the combustion chamber.

5. Inlet temperature sensors These sensors monitor system return water temperature.

6. Outlet temperature sensors/High Limits These sensors monitor water heater outlet water temperature. The water heater modulates based on the Lead Lag Sensor connected

to the tank.

7. Burners

Made with metal ber and stainless steel construction, the burners use pre-mixed air and gas and provide a wide range of ring rates.

8. Condensate Trap Disposes the condensate produced from heat exchanger and houses a switch that detects in case of blockage.

9. Control modules The control modules respond to internal and external signals and control the blowers, gas valves, and pumps to meet the heating demand.

10. Touch Screen Display Digital controls with touch screen technology and full color display.

11. Sight glass The quartz sight glass provides a view of the ame for inspection

purposes.

12. Flame sensors

Used by the control module to detect the presence of burner ame.

13. Flap valves Prevents recirculation of ue products when only one burner is

running.

14. Flue gas sensors (not visible)

These sensors monitor the ue gas exit temperature. The control modules will modulate and shut down the water heater if the ue gas temperature gets too hot. This protects the ue pipe from

overheating.

15. Flue pipe adapter (not visible)

Allows for the connection of the PVC vent pipe system to the water heater.

16. Gas shutoff valves (Internal unit) Manual valves used to isolate the gas valves from the burners.

17. Main gas shutoff valve (External unit) Manual valve used to isolate the water heater from the gas supply.

18. Automatic modulating gas valve The gas valve with the addition of venturi and blower are used for modulating premix appliances.

19. Heat exchanger access covers Allows access to the combustion side of the heat exchanger coils.

20. High gas pressure switch Switch provided to detect excessive supply gas pressure.

21. Spark Igniter

Provides direct spark for igniting the burners.

22. Power supply terminals (not visible) The main power to the water heater is supplied through the terminals housed inside the high voltage junction box.

23. Low gas pressure switch Switch provided to detect low gas supply pressure.

24. High voltage connection box This box has terminals for connecting the main power supply (120V) to the water heater and outputs power supply (120V) for the pumps from the water heater control. This box has terminals for low voltage devices such as condensate trap and ow switch.

25. Sensors/Communication Box Connects sensors to tank sensor/header sensor and external connections to building managements systems through MODBUS.

26. Low water cutoff board and sensor probe (LWCO) Device used to ensure adequate water is supplied to the water heater. In the event of inadequate water levels, LWCO will ensure water heater shut down. LWCO board is connected to the electronic panel, whereas the sensor probe is connected to the heat exchanger.

27. Main power supply switch Turns 120 VAC ON/OFF to the water heater.

28. Pump relay The pump relays are used for providing power to the water

heater.

29. Pressure relief valve

Protects the heat exchangers from an over pressure condition. The relief valve will be set at particular PSI, depending on models.

30. Reset switch (optional) (not visible) Reset switch for the low water cutoff.

31. Stainless steel heat exchangers Allows system water to ow through specially designed coils.

32. Venturi The venturi is a gas/air mixing unit that allows modulation of a premix burner with constant gas/air ratio.

33. Water inlet Water connection that return water from the system to the heat exchangers.

34. Water outlets A NPT water connection that supplies hot water to the system.

35. Enable/Disable Switch This is an emergency water heater turn off switch which disconnects the interlock voltage to the control board, hence turning off the power supply to the gas valves. Do not use this

switch for turning off the water heater, this should be done from the touch screen display, using the Operational Switch on the Lead Lag screen.

36. Vent outlet Provides an outlet for combustion gases to outdoor.

CONTROL COMPONENTS

THE CONTROL SYSTEM

The R7910A1138 is a burner control system that provides heat control, ame supervision, circulation pump control, fan control, water heater control sequencing, and electric ignition function. It will also provide status and error reporting.

FIGURE 5. BURNER CONTROL SYSTEM

SPARK IGNITER

FIGURE 7. LOW/HIGH GAS PRESSURE SWITCH

GAS CONTROL VALVE

The gas valve is a normally closed servo regulated gas valve. The valve opens only when energized by the burner control and closes when the power is removed. The burner control supplies 24 volts to the gas valve during operation.

The spark igniter is a device that ignites the main burner. When power is supplied to the igniter electrode, an electric arc is created between the electrode and the ground terminal which ignites the main burner.

FIGURE 6. SPARK IGNITER

LOW/HIGH GAS PRESSURE SWITCH

This XWH is equipped with a low gas pressure switch which meets the CSD-1 code requirements.

The Low Gas Pressure Switch is normally open and remains open if the pressure is below the preset pressure. It closes as soon as the gas supply pressure is above the minimum supply

pressure.

The High Gas Pressure Switch is normally closed and is used to detect excessive gas pressure.

HIGH FIRING

RATE SETTING

LOW FIRING

RATE SETTING

FIGURE 8. GAS CONTROL VALVE

WATER FLOW SWITCH

The water ow switch activates when sufcient water ow has been established. Switch will not close when water ow is not

present.

FIGURE 9. WATER FLOW SWITCH

FLAME SENSOR

Each burner is equipped with a ame sensor to detect the presence of the burner ames at high and low re conditions. If no ame is sensed, the gas valve will close automatically. The voltage sensed by the ame sensor will also be displayed on the Burner Screen.

FIGURE 10. FLAME SENSOR

WATER TEMPERATURE LIMIT CONTROLS

This water heater incorporates an outlet water sensor having dual sensors, that are factory set at 210°F (99°C).

MAIN POWER SUPPLY SWITCH

The main power supply switch is a padlockable switch. This switch pro vides 120V from the power supply to the water heater.

This switch needs to be turned off when servicing the water heater. NOTE: The Enable/Disable (Interlock) Switch on the front of the water heater does not interrupt electrical power to the water heater.

WATER TEMPERATURE SENSORS

FIGURE 12. WATER TEMPERATURE SENSORS

Temperature sensors are threaded immersion probes. Temperature probes have embedded temperature sensors (thermistors). The water heater’s control system monitors these sensors to determine water temperature at various points in the system.

INLET AND OUTLET TEMPERATURE SENSORS

All models have two inlet and two outlet temperature sensors for each heat exchanger, factory installed to monitor the water temperature entering and leaving the water heater. The Inlet Probe is a temperature sensor only and has two leads. The Outlet probe also contains the manual reset high temperature limit switch and has four leads. The control system displays the Inlet and Outlet water temperatures sensed from these two sensors on the default Temperatures screen.

REMOTE SENSORS

All models are supplied from the factory with a remote sensor. The remote sensor is used to control system water temperature for a single water heater in a domestic hot water storage tank.

The water heater will modulate its ring rate in response to the actual system temperature and load conditions. The control system displays the temperature sensed from the remote sensor as the “Lead Lag” temperature on the default Temperatures screen.

FIGURE 11. MAIN POWER SUPPLY SWITCH

LOW WATER CUTOFF DEVICE (LWCO)

Low water cutoff device is normally a closed switch that opens when water drops below a preset level. Each model is equipped with a factory installed LWCO. LWCO board is connected to the electronic panel, whereas the sensor probe is connected to the heat exchanger.

FIGURE 13. LWCO BOARD AND PROBE

INSTALLATION CONSIDERATIONS

GENERAL

If the system is to be lled with water for testing or other purposes during cold weather and before actual operation, care must be taken to prevent freezing of water in the system. Failure to do so may cause the water in the system to freeze with resulting damage to the system.

Damage due to freezing is not covered by the warranty.

Figure 76 on Page 79 shows a typical primary, secondary piping method. This is the preferred piping method for most circulating water heaters. Other piping methods, however, may provide good system operation. A prime concern when designing heating systems is the maintenance of proper ow through the unit during water heater operation. The secondary pump should be sized per the recommended ow rate of the water heater, see Dimension and Capacity Data section in this manual.

Before locating the water heater:

1. Check for nearby connection to:

• System water piping

• Venting connections

• Gas supply piping

• Electrical power

2. Locate the water heater so that if water connections should

leak, water damage will not occur. When such locations cannot be avoided, it is recommended that a suitable drain pan, adequately drained, be installed under the appliance. The pan must not restrict combustion air ow. Under no circumstances is the manufacturer to be held responsible for water damage in connection with this appliance, or any of its components.

3. Check area around the water heater. Remove any

combustible materials, gasoline and other ammable liquids.

4. Make sure the gas control system components are protected

from dripping or spraying water or rain during operation or service.

5. If a new water heater will replace an existing water heater,

check for and correct system problems, such as:

• System leaks causing oxygen corrosion or heat exchanger cracks from hard water deposits.

• Lack of freeze protection in water heater water causing system and water heater to freeze and leak.

PRIMARY SYSTEM CONTROL

All XWH installations require a “Primary System Control” that senses and reacts to water temperature inside the storage tank on domestic water applications. The Primary System Control will activate and deactivate water heater heating cycles based on its setpoint and current system water temperature. There are three suitable methods to congure a Primary System Control. One of these three methods must be used.

1. The Primary System Control can be the water heater’s control system working with the factory supplied Header Sensor, installed inside the storage tank on domestic water applications.

2. Alternatively, the Burner Control system can be used as a Primary System Control. It will also provide water heater status and error reporting. Multiple water heaters can be joined together to heat a system instead of a single, larger burner or water heater. Using water heaters in parallel is more efcient, costs less, reduces emissions, improves load control, and is more exible than the traditional large water

heater.

3. MB2 and COM2 ports can be used for Building Management Systems.

INTERNAL CONTAMINANTS

The system must be internally cleaned and ushed after a new or replacement water heater has been installed, to remove contaminants that may have accumulated during installation. This is extremely important when a replacement water heater is installed into an existing system where Stop Leak or other water heater additives have been used.

Failure to clean and ush the system can produce acid concentrations that become corrosive, and leads to heat exchanger failure.

All hot water heating systems should be completely ushed with a grease removing solution to assure trouble-free opera tion. Pipe joint compounds, soldering paste, grease on tubing and pipe all tend to contaminate a system

Failure to ush contaminants from a system can cause solids to form on the inside of heat exchangers, create excessive blockage of water circulation, deterioration of the pump seals and impellers.

WATER LINE CONNECTIONS

CIRCULATING PUMP

A circulating pump is used when a system requires a circulating loop or there is a storage tank used in conjunction with the water heater. Install in accordance with the current edition of the National Electrical Code, NFPA 70 or the Canadian Electrical Code, CSA C22.1. All bronze circulating pumps are recommended for use with commercial water heaters. Some circulating pumps are manufactured with sealed bearings and do not require further lubrication. Some circulating pumps must be periodically oiled. Refer to the pump manufacturer’s instructions for lubrication requirements.

XWH Models: The circulating pump is integral to the XWH models. This pump has been lubricated at the factory, and future lubrication should be in accordance with the motor manufacturer’s instructions provided as a supplement to this manual.

Piping diagrams will serve to provide the installer with a reference for the materials and methods of piping necessary for installation. It is essential that all water piping be installed and connected as shown on the diagrams. Check the diagrams to be used thoroughly before starting installation to avoid possible errors and to minimize time and material cost. It is essential that all water piping be installed and connected as shown on the diagrams. See Figure 76 on Page 79 and Figure 77 on Page 80.

CLOSED WATER SYSTEMS

Water supply systems may, because of code requirements or such conditions as high line pressure, among others, have installed devices such as pressure reducing valves, check valves, and back ow preventers. Devices such as these cause the water system to be a closed system.

THERMAL EXPANSION

As water is heated, it expands (thermal expansion). In a closed system the volume of water will increase when it is heated. As the volume of water increases there will be a corresponding increase in water pressure due to thermal expansion. Thermal expansion can cause premature failure (leakage). This type of failure is not covered under the limited warranty. Thermal expansion can also cause intermittent Temperature-Pressure Relief Valve operation: water discharged from the valve due to excessive pressure build up. This condition is not covered under the limited warranty. The Temperature-Pressure Relief Valve is not intended for the constant relief of thermal expansion.

A properly sized thermal expansion tank must be installed on all closed systems to control the harmful effects of thermal expansion. Contact a local plumbing service agency to have a thermal expansion tank installed.

PRESSURE RELIEF VALVE

An ASME rated pressure relief valve is furnished with the water heater. A tting for the relief valve is provided in the top of the water heater. Never operate the heating elements without being certain the water heater is lled with water and a properly sized pressure relief valve is installed in the relief valve opening provided.

The pressure rating of the relief valve should be equal to or less than the rated pressure capacity of any component in the system including the water heater. Should the valve need to be replaced, call the toll free phone number listed on the back of this manual for further technical assistance

Explosion Hazard

Relief Valve must comply with ASME code.

Properly sized Relief Valve must be installed in opening provided.

Can result in overheating and excessive tank pressure.

Can cause serious injury or death.

A discharge pipe from the relief valve should terminate at an adequate oor drain. Do not thread, plug, or cap the end of drain line.

CAUTION

Water Damage Hazard

• Pressure Relief Valve discharge pipe must

terminate at adequate drain.

The Discharge Pipe:

• Shall not be smaller in size than the outlet pipe size of the valve, or have any reducing couplings or other restrictions.

• Shall not be plugged or blocked.

• Shall not be exposed to freezing temperatures.

• Shall be of material listed for hot water distribution.

• Shall be installed so as to allow complete drainage of both the relief valve and the discharge pipe.

• Must terminate a maximum of six inches above a oor drain or external to the building. In cold climates, it is recommended that the discharge pipe be terminated at an adequate drain inside the building.

• Shall not have any valve or other obstruction between the relief valve and the drain.

Once the water heater is installed and lled with water and the system is pressurized, manually test the operation of the pressure relief valve. See the Maintenance Procedures section of this manual for instructions.

Your local code authority may have other specic safety relief valve requirements not covered below. If any pressure relief valve is re placed, the replace ment valve must com ply with the requirements for Relief Valves for Hot Water Supply Systems, ANSI Z21.22 • CSA 4.4, and the code requirements of ASME.

XWH water heaters are shipped with a 125 psi (860 kPa) pressure relief valve that must be in stalled in the water out let as near to the water heater as possi ble.

This ASME-rated valve has a discharge capacity that exceeds maximum water heater input rating and a pres sure rating that does not exceed maxi mum working pres sure shown on water heater rating plate.

In addition, a CSA design-certied and ASME-rated tempera ture and pressure (T&P) relief valve must be installed on each and every water storage tank in hot water supply system. The T&P relief valve must comply with appli cable construction provisions of Standard for Relief Valves for Hot Water Supply Systems, ANSI Z21.22 or CSA 4.4. T&P re lief valve must be of automatic reset type and not embody a single-use type fusible plug, cartridge or linkage.

T&P relief valve should have a temperature rating of 210°F (99°C), a pressure rating not exceeding lowest rated working pressure of any system compo nent, and a discharge capacity exceeding total input of water heaters supply ing water to storage

tank.

Locate the T&P relief valve (a) in the top of the tank, or (b) in the side of the tank on a centerline within the upper 6 inches (152 mm) of the top of the tank, see Figure 76 and Figure 77. The tapping should be threaded in accordance with the current edition of the Standard for Pipe Threads, General Purpose (inch), ANSI/A SME B1.20.1. The location of, or in tended location for, the T&P relief valve should be readily accessible for servicing or replacement.

GAS CONNECTIONS

Make sure the gas on which water heater is to operate is same as that specied on the rating plate. Do not install water heater if equipped for a different type of gas. Consult your gas supplier.

This water heater is not intended to operate at gas supply pressure other than shown on the rating plate. A lock-up or positive shut-off type regulator must be installed in gas supply line. For proper gas regulation the lock-up style regulators must be installed no closer than a minimum of 3 feet (0.9 m) from the water heater and a maximum of 8 feet (2.4 m) away from the

water heater. Exposure to higher gas supply pressure may cause damage to gas valves which can result in re or explosion. If overpressure has occurred such as through improper testing of gas lines or emergency malfunction of supply system, the gas valves must be checked for safe operation. Make sure that the outside vents on supply regulators and the safety vent valves are protected against blockage. These are parts of the gas supply system, not water heater. Vent blockage may occur during ice build-up or snowstorms.

The water heater must be isolated from the gas supply piping system by closing its main manual gas shut off valve during any pressure testing of the gas supply piping system at test pressures equal to or less than 1/2 psig.

Disconnect the water heater and its main manual gas shut-off valve from the gas supply piping during any pressure testing of the gas supply system over 1/2 psig. The gas supply line must be capped when not connected to the water heater.

It is important to guard against gas valve fouling from contaminants in the gas ways. Such fouling may cause improper operation, re or explosion. If copper supply lines are used they must be approved for gas service.

When local codes require a main manual shut-off valve outside the water heater jacket, a suitable main manual shut-off valve must be installed in a location complying with those codes.

Before attaching gas line be sure that all gas pipe is clean on inside. To trap any dirt or foreign material in the gas supply line, a sediment trap must be incorporated in piping. The sediment trap must be readily accessible and not subject to freezing conditions. Install in accordance with recommendations of serving gas supplier. Refer to the current edition of the National Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and Propane Installation Code, CAN/CSA B149.1

Size of gas supply piping may be larger than heater connection on installations where a signicant run of piping is required.

To prevent damage, care must be taken not to apply too much torque when attaching gas supply pipe to water heater gas inlet. When installing and tightening gas piping use a second wrench to hold the gas valve to keep the valve from turning. To prevent damage to the gas valve do not use pipe wrench on the valve body.

Fittings and unions in gas line must be of metal to metal type. Apply joint compounds (pipe dope) sparingly and only to the male threads of pipe joints. Do not apply compound to the rst two threads. Use compounds resistant to the action of liqueed petroleum gases. The water heater and its gas connection must be leak tested before placing the water heater in operation.

GAS SUPPLY LINE SIZING

The gas piping installation must be capable of supplying the maximum probable gas demand without excessive pressure loss. Depending on local practices, the ALLOWABLE PRESSURE LOSS between the gas meter, or service regulator and each

appliance is generally 0.3 or 0.5 inches of water column (0.075 or 0.124 kPa).

For single water heater installation, refer to Table 7 and Table 8 to size iron pipe or equivalent gas supply line size to be used with single unit.

For multiple water heater installation or installations of a single water heater with other gas appliances, please refer to Table 9 and Table 10 on Page 19 to size iron pipe or equivalent gas supply line. These tables are taken from the current edition of the National Fuel Gas Code, ANSI Z223.1/NFPA 54 or the Natural Gas and Propane Installation Code, CAN/CSA B149.1.

• Table 9 is based on a pressure drop of 0.5 inches water column (0.124 kPa), and a gas with a specic gravity of

0.60 and a heating value of 1,000 BTU/ft3, approximately that of Natural Gas.

• Table 10 is based on a pressure drop of 0.5 inches water column (0.124 kPa), and a gas with a specic gravity of

1.53 and a heating value of 2,500 BTU/ft3, approximately

that of Propane Gas.

Where it is necessary to use more than the average number of ttings (i.e., elbows, tees and valves in gas supply line) use a pipe larger than specied to compensate for increased pressure drop.

Table 7 and Table 8 shows the maximum equivalent gas pipe length for a single unit installation. It does not take into account other appliances that may be connected to the gas line. For installation of multiple units, or instances where several appliances are connected to the same line, use Table 9 and Table 10 for proper sizing.

TABLE 7.

SINGLE UNIT INSTALLATION, SUGGESTED GAS PIPE

SIZING. MAXIMUM EQUIVALENT PIPE LENGTH (IN FEET).

BTU

Input

920,000 70 150 175 ----- ----- ----- ----- -----

1,300,000 40 100 100 200 ----- ----- ----- -----

1,700,000 20 60 70 150 200 ----- ----- -----

2,000,000 20 50 50 100 150 ----- ----- -----

2,600,000 10 30 30 70 90 200 ----- -----

3,400,000 ----- ----- 20 40 50 125 200 -----

Natural gas 1000 Btu/ft^3, 0.60 specic gravity @ 0.3 in. w.c. pressure drop. Propane gas 2500 Btu/ft^3, 1.50 specic gravity @ 0.3 in. w.c. pressure drop.

2” 2-1/2” 3” 4”

Nat Pro Nat Pro Nat Pro Nat Pro

TABLE 8.

SINGLE UNIT INSTALLATION, SUGGESTED GAS PIPE

SIZING. MAXIMUM EQUIVALENT PIPE LENGTH (IN FEET).

BTU

Input

920,000 125 200 200 ----- ----- ----- ----- -----

1,300,000 80 175 175 ----- ----- ----- ----- -----

1,700,000 40 100 100 ----- ----- ----- ----- -----

2,000,000 30 80 80 200 200 ----- ----- -----

2,600,000 20 50 50 125 150 ----- ----- -----

3,400,000 10 30 30 70 90 200 ----- -----

Natural gas 1000 Btu/ft^3, 0.63 specic gravity @ 0.5 in. w.c. pressure drop. Propane gas 2500 Btu/ft^3, 1.50 specic gravity @ 0.5 in. w.c. pressure drop.

2” 2-1/2” 3” 4”

Nat Pro Nat Pro Nat Pro Nat Pro

CORROSIVE MATERIALS AND CONTAMINATION SOURCES

Products to avoid:

• Spray cans containing chloro/uorocarbons

• Permanent wave solutions

• Chlorinated waxes/cleaners

• Chlorine-based swimming pool chemicals

• Calcium chloride used for thawing

• Sodium chloride used for water softening

• Refrigerant leaks

• Paint or varnish removers

• Hydrochloric acid/muriatic acid

• Cements and glues

• Antistatic fabric softeners used in clothes dryers

• Chlorine-type bleaches, detergents, and cleaning solvents found in household laundry rooms

• Adhesives used to fasten building products and other similar products

Areas likely to have contaminants:

• Dry cleaning/laundry areas and establishments

• Swimming pools

• Metal fabrication plants

• Beauty shops

• Refrigeration repair shops

• Photo processing plants

• Auto body shops

• Plastic manufacturing plants

• Furniture renishing areas and establishments

• New building construction

• Remodeling areas

Common household products, pool and laundry products may contain uorine or chlorine compounds. When these chemicals come in contact with the water heater, they react and can form strong acids. The acid can spoil the water heater wall, causing serious damage and may result in ue gas spillage or water heater water leakage into the building.

If the above mentioned contaminants and corrosive materials chemicals are present near the location of the water heater, make sure to remove the water heater permanently or relocate air inlet and vent terminations to other areas.

FIELD WIRING

POWER SUPPLY CHECK

To reduce the possibility of electrical interference with the water heater’s control system the power supply voltage, polarity and ground must be checked. Using an AC volt meter check the 120 VAC power supply wiring from the breaker prior to making power supply connections at the water heater. Conrm the power supply voltage & polarity are correct and that an adequate ground connection is present by performing the three voltage tests below. See Figure 14 for wiring references.

Conrm RMS voltage between:

• H and GND = 108 VAC minimum, 132 VAC maximum.

• N and H = 108 VAC minimum, 132 VAC maximum.

• N and GND = < 1 VAC maximum.

FIGURE 14. FIELD WIRING

LOW VOLTAGE CONTROL WIRING

1. Header Terminals: In XWH water heaters the header

terminals are connected to the tank sensor where the temperature can be sensed. See Figure 15. The tank sensor is to be connected using the factory supplied sensor harness. The maximum length of the wire connecting from the water heater to the outdoor sensor must be no more than 50 feet (15.2 m).

2. MB2 and COM2 terminals are meant for building

management systems.

120 VAC POWER SUPPLY WIRING

A dedicated, single phase, 30-60 amp (refer to Table 5 on Page

8) circuit breaker with a grounded neutral should be provided to supply power to the water heaters. Use #10 AWG wire for the 120 VAC power supply to the water heater. All 120 VAC power supply connections must be made as shown in Figure 14. These connections should be made at the rear of the unit where a wiring junction box is provided. Field installed power supply wiring to the water heater should be installed in conduit. This conduit and wiring should be separate from any other conduit/wiring to guard against EMI (electromagnetic interference).

FIGURE 15. LOW VOLTAGE CONTROL WIRING

All low voltage control wiring connections must be made as shown in Figure 14. These connections should be made at the rear of the unit where a wiring junction box is provided. Field installed wiring inside 1/2 inch conduit is installed between the junction box on the back of the water heater and the temperature probe and/or eld supplied external control being used. This conduit and wiring should be separate from any other conduit/ wiring to guard against EMI (electromagnetic interference).

TABLE 9. SUGGESTED PIPE SIZE FOR MULTIPLE GAS APPLIANCES (NATURAL GAS)

Nominal Maximum Capacity of Pipe in BTU/hr and kW for Gas Pressures of 14 in. W.C. (0.5 psi) or Less and

Iron Pipe a Pressure Drop of 0.5 in. W.C. (based on 0.60 Specic Gravity Gas w/Heating Value of 1,000 BTU’s/Ft3)

Size Length of Pipe in Feet (Meters)

(Inches) 10 (3.05) 20 (6.1) 30 (9.14) 40 (12.19) 50 (15.24) 60 (18.29) 70 (21.34) 80 (24.38) 90 (27.43) 100 (30.48) 125 (38.1) 150 175 200

1 1/2 BTU/hr 2,100,000 1,460,000 1,180,000 990,000 900,000 810,000 750,000 690,000 650,000 620,000 550,000 500,000 460,000 —

kW 615 428 346 290 264 237 220 202 190 182 161 146 135 —

2 BTU/hr 3,950,000 2,750,000 2,200,000 1,900,000 1,680,000 1,520,000 1,400,000 1,300,000 1,220,000 1,150,000 1,020,000 950,000 850,000 800,000

kW 1,157 805 644 556 492 445 410 381 357 337 299 278 249 234

2 1/2 BTU/hr 6,300,000 4,350,000 3,520,000 3,000,000 2,650,000 2,400,000 2,250,000 2,050,000 1,950,000 1,850,000 1,650,000 1,500,000 1,370,000 1,280,000

kW 1,845 1,274 1,031 879 776 703 659 600 571 542 483 439 401 375

3 BTU/hr 11,000,000 7,700,000 6,250,000 5,300,000 4,750,000 4,300,000 3,900,000 3,700,000 3,450,000 3,250,000 2,950,000 2,650,000 2,450,000 2,280,000

kW 3,222 2,255 1,830 1,552 1,391 1,259 1,142 1,084 1,010 952 864 776 718 668

4 BTU/hr 23,000,000 15,800,000 12,800,000 10,900,000 9,700,000 8,800,000 8,100,000 7,500,000 7,200,000 6,700,000 6,000,000 5,500,000 5,000,000 4,600,000

kW 6,736 4,627 3,749 3,192 2,841 2,577 2,372 2,197 2,109 1,962 1,757 1,611 1,464 1,347

TABLE 10. SUGGESTED PIPE SIZE FOR MULTIPLE GAS APPLIANCES (PROPANE GAS)

Nominal Maximum Capacity of Pipe in BTU/hr and kW for Gas Pressures of 14 in. W.C. (0.5 psi) or Less and

Iron Pipe a Pressure Drop of 0.5 in. W.C. (based on 0.60 Specic Gravity Gas w/Heating Value of 1,000 BTU’s/Ft3)

Size Length of Pipe in Feet (Meters)

(Inches) 10 (3.05) 20 (6.1) 30 (9.14) 40 (12.19) 50 (15.24) 60 (18.29) 70 (21.34) 80 (24.38) 90 (27.43) 100 (30.48) 125 (38.1) 150 175 200

1 1/2 BTU/hr 3,276,000 2,277,600 1,840,800 1,544,400 1,404,000 1,263,600 1,170,000 1,076,400 1,014,000 967,200 858,000 780,000 717,600 670,800

kW 959 667 539 452 411 370 343 315 297 283 251 228 210 196

2 BTU/hr 6,162,000 4,290,000 3,432,000 2,964,000 2,620,800 2,371,200 2,184,000 2,028,000 1,903,200 1,794,000 1,591,200 1,482,000 1,326,000 1,248,000

kW 1,805 1,256 1,005 868 768 694 640 594 557 525 466 434 388 366

2 1/2 BTU/hr 9,828,000 6,786,000 5,491,200 4,680,000 4,134,000 3,744,000 3,510,000 3,198,000 3,042,000 2,886,000 2,574,000 2,340,000 2,137,200 1,999,800

kW 2,878 1,987 1,608 1,371 1,211 1,097 1,028 937 891 845 754 685 626 585

3 BTU/hr 17,160,000 12,012,000 9,750,000 8,268,000 7,410,000 6,708,000 6,084,000 5,772,000 5,382,000 5,070,000 4,602,000 4,134,000 3,822,000 3,556,800

kW 5,026 3,518 2,856 2,421 2,170 1,965 1,782 1,690 1,576 1,485 1,348 1,211 1,119 1,042

4 BTU/hr 35,880,000 24,648,000 19,968,000 17,004,000 15,132,000 13,728,000 12,636,000 11,700,000 11,232,000 10,452,000 9,360,000 8,580,000 7,800,000 7,176,000

kW 10,508 7,219 5,848 4,980 4,432 4,021 3,701 3,427 3,290 3,061 2,741 2,513 2,284 2,102

GENERAL REQUIREMENTS

REQUIRED ABILITY

Installation or service of this water heater requires ability equivalent to that of a licensed trades man in the eld involved. Plumbing, air supply, venting, gas supply, and electrical work are re quired.

LOCATION

When installing the water heater, consideration must be given to proper location. The location selected should provide adequate air supply and be as centralized with the piping system as possible.

REPLACING EXISTING COMMON VENTED WATER HEATER

NOTE: This section does not describe a method for common venting XWH units. It describes what must be done when a unit is removed from a common vent system. The XWH units require special vent systems and fans for common vent. Contact the factory if you have questions about common venting XWH units.

When an existing water heater is removed from a common venting system, the common venting system is likely to be too large for proper venting of the appliances remaining connected to it. At the time of removal of an existing water heater, the following steps should be followed with each appliance remaining connected to the common venting system placed in operation, while the other appliances remaining connected to the common venting system

are not in operation.

1. Seal any unused openings in the common venting system.

2. Visually inspect the venting system for proper size and

horizontal pitch and determine there is no blockage or restriction, leakage, corrosion and deciencies which could cause an unsafe condition.

3. In so far as it is practical, close all building doors and

windows and all doors between the space in which the appliances remaining connected to the common venting system are located and other spaces of the building. Turn on clothes dryers and any appliance not connected to the common venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, so they will operate at maximum speed. Do not operate a summer exhaust fan. Close replace dampers.

4. Place in operation the appliance being inspected. Follow the

lighting instructions. Adjust thermostat so the appliance will operate continuously.

5. Test for spillage at the draft hood relief opening after 5

minutes of main burner operation. Use the ame of a match or candle, or smoke from a cigarette, cigar or pipe.

6. After it has been determined that each appliance remaining

connected to the common venting system properly vents when tested as outlined above, return doors, windows, exhaust fans, replace dampers and any other gas-burning appliance to their previous condition of use.

7. Any improper operation of the common venting system

should be corrected so that the installation conforms with the National Fuel Gas Code, ANSI Z223.1/NFPA 54 and/ or CSA B149.1, Installation Codes. When resizing any portion of the common venting system, the common venting system should be resized to approach the minimum size as determined using the appropriate tables and guidelines in the National Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or CSA B149.1, Installation Codes.

This water heater is intended for Indoor Installation only, and should not be installed where freezing temperatures or any moisture could damage the external components of the water

heater.

PANELS AND COVERS

All panels and covers (e.g. control and junction box covers; front, side and rear panels of water heater) must be in place after service and/or before opera tion of water heater. This will ensure that all gas ignition components will be protected from water.

The XWH is a low-pressure water heater to be used as hot water heating (potable water only) applications.

CHEMICAL VAPOR CORROSION

Water heater corrosion and component failure can be caused by the heating and breakdown of airborne chemical vapors. Spray can propellants, cleaning sol vents, refrigerator and air conditioning refrig erants, swimming pool chemicals, calcium and sodium chloride (water softener salt), waxes, and process chemicals are typical compounds which are potentially corrosive. These materials are corrosive at very low concentration levels with little or no odor to reveal their presence.

Products of this sort should not be stored near water heater. Also, air which is brought in contact with water heater should not contain any of these chemicals. If necessary, uncontaminated air should be obtained from remote or outside sources. Failure to observe this requirement will void warranty.

INSTALLATION CLEARANCES

This water heater is approved for installation in an alcove with minimum clearances to combustibles.

TABLE 11. INSTALLATION CLEARANCES

RECOMMENDED

SERVICE

CLEARANCES

Front 30" (762 mm) 8" (203 mm)

Rear 36" (610 mm) 24" (610 mm)

Left 24 " (610 mm) 1" (25.4 mm)

Right 24 " (610 mm) 2" (51 mm)

Top 24" (610 mm) 6" (152 mm)

2” (51 mm) clearance is allowable from combustible construction for hot water pipes.

Sufcient area should be provided at the front and rear of the unit for prop er servicing. In a utility room installa tion, the door opening should be wide enough to allow the water heater to enter or to permit the replacement of another appli ance such as a water heater.

FLOORING AND FOUNDATION:

All models are approved for installation on combustible ooring, but must never be installed on carpeting. Do not install the water heater on carpeting even if foundation is used. Fire can result, causing severe personal injury, death, or substantial property damage.

If ooding is possible, elevate the water heater sufciently to prevent water from reaching the water heater.

CLEARANCES FROM

COMBUSTIBLE

MATERIALS

LEVELING

Because this unit is a condensing unit, it has a condensation disposal system that requires this unit to be level to properly drain. Each unit should be checked to be certain that it is level

prior to starting the unit.

If the unit is not level, obtain and insert shims under the feet at the frame base to correct this condition.

AIR REQUIREMENTS

Breathing Hazard - Carbon Monoxide Gas

Install appliance in accordance with the Instruction Manual and NFPA 54 or CAN/CSA-B149.1.

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.

For safe operation an adequate supply of fresh uncontaminated air for combustion and ventilation must be provided.

An insuf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 ame, causing sooting of the combustion chamber, burners and ue tubes and creates a risk of asphyxiation.

Do not install the water heater in a conned space unless an adequate supply of air for combustion and ventilation is brought in to that space using the methods described in the Conned Space section that follows.

Never obstruct the ow of ventilation air. 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 re or explosion and cause property damage, serious bodily injury or death.

UNCONFINED SPACE

An unconned space is one whose volume is not less than 50 cubic feet per 1,000 Btu/hr (4.8 cubic meters per kW) 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 unconned space.

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

UNUSUALLY TIGHT CONSTRUCTION

In unconned spaces in buildings, inltration may be adequate to provide air for combustion, ventilation and dilution of ue gases. However, in buildings of unusually tight construction (for example, weather stripping, heavily insulated, caulked, vapor barrier, etc.) additional air must be provided using the methods described in the Conned Space section that follows.

CONFINED SPACE

A conned space is one whose volume is less than 50 cubic feet per 1,000 Btu/hr (4.8 cubic meters per kW) 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 conned spaces. The required size for the openings is dependent on the method used to provide fresh air to the conned space and the total Btu/hr input rating of all appliances installed in the space.

DIRECT VENT APPLIANCES

Appliances installed in a direct vent con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 conned spaces.

EXHAUST FANS

Where exhaust fans are installed, additional air shall be provided to replace the exhausted air. When an exhaust fan is installed in the same space with a water heater, suf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 re or explosion may result. It can also create a risk of asphyxiation.

LOUVERS AND GRILLES

The free areas of the fresh air openings in the instructions that follow do not take in to account the presence of louvers, grilles or screens in the openings.

The required size of openings for combustion, ventilation and dilution air shall be based on the “net free area” of each opening. Where the free area through a design of louver or grille or screen is known, it shall be used in calculating the size of opening required to provide the free area specied. Where the louver and grille design and free area are not known, it shall be assumed that wood louvers will have 25% free area and metal louvers and grilles will have 75% free area. Non motorized louvers and grilles shall be xed in the open position.

OUTDOOR AIR THROUGH TWO OPENINGS

FIGURE 16. OUTDOOR AIR THROUGH TWO OPENINGS

The conned space shall be provided with two permanent openings, one commencing within 12 inches (300 mm) of the top and one commencing within 12 inches (300 mm) of the bottom of the enclosure. The openings shall communicate directly with the outdoors. See Figure 16.

Each opening shall have a minimum free area of 1 square inch per 4,000 Btu/hr (550 mm2 per kW) of the aggregate input rating of all appliances installed in the enclosure. Each opening shall not be less than 100 square inches (645 cm2).

OUTDOOR AIR THROUGH ONE OPENING

FRESH AIR OPENINGS FOR CONFINED SPACES

The following instructions shall be used to calculate the size, number and placement of openings providing fresh air for combustion, ventilation and dilution in conned spaces. The illustrations shown in this section of the manual are a reference for the openings that provide fresh air into conned spaces only. Do not refer to these illustrations for the purpose of vent installation. See Venting section on Page 24 for complete venting installation instructions.

FIGURE 17. OUTDOOR AIR THROUGH ONE OPENING

Alternatively a single permanent opening, commencing within 12 inches (300 mm) of the top of the enclosure, shall be provided. See Figure 17. The water heater shall have clearances of at least 1 inch (25 mm) from the sides and back and 6 inches (150 mm) from the front of the appliance. The opening shall directly communicate with the outdoors or shall communicate through a vertical or horizontal duct to the outdoors or spaces that freely communicate with the outdoors and shall have a minimum free area of the following:

1. 1 square inch per 3000 Btu/hr (700 mm2 per kW) of the total

input rating of all appliances located in the enclosure, and

2. Not less than the sum of the areas of all vent connectors in

the space.

OUTDOOR AIR THROUGH TWO HORIZONTAL DUCTS

FIGURE 18. OUTDOOR AIR THROUGH TWO HORIZONTAL

DUCTS

The conned space shall be provided with two permanent horizontal ducts, one commencing within 12 inches (300 mm) of the top and one commencing within 12 inches (300 mm) of the bottom of the enclosure. The horizontal ducts shall communicate directly with the outdoors. See Figure 18.

Each duct opening shall have a minimum free area of 1 square inch per 2,000 Btu/hr (1100 mm2 per kW) of the aggregate input rating of all appliances installed in the enclosure.

When ducts are used, they shall be of the same cross sectional area as the free area of the openings to which they connect. The minimum dimension of rectangular air ducts shall be not less than 3 inches.

OUTDOOR AIR THROUGH TWO VERTICAL DUCTS

The illustrations shown in this section of the manual are a reference for the openings that provide fresh air into conned spaces only.

Do not refer to these illustrations for the purpose of vent installation.

The conned space shall be provided with two permanent vertical ducts, one commencing within 12 inches (300 mm) of the top and one commencing within 12 inches (300 mm) of the bottom of the enclosure. The vertical ducts shall communicate directly with the outdoors. See Figure 19.

Each duct opening shall have a minimum free area of 1 square inch per 4,000 Btu/hr (550 mm2 per kW) of the aggregate input rating of all appliances installed in the enclosure.

AIR FROM OTHER INDOOR SPACES

FIGURE 20. AIR FROM OTHER INDOOR SPACES

Each opening shall communicate directly with an additional room(s) of sufcient volume so that the combined volume of all spaces meets the criteria for an Unconned Space.

Each opening shall have a minimum free area of 1 square inch per 1,000 Btu/hr (1100 mm2 per kW) of the aggregate input rating of all appliances installed in the enclosure. Each opening shall not be less than 100 square inches (645 cm2).

FIGURE 19. OUTDOOR AIR THROUGH TWO VERTICAL

DUCTS

VENTING

VENT INSTALLATION CONSIDERATIONS

This water heater can be vented using room air for intake combustion air, or direct vented so that all intake air for combustion comes from the outside through a sealed pipe. When installing this appliance as direct vent, use the recommended terminations in this section, refer to Page 27 till Page 30.

In cold climates any water vapor remaining in the ue gases will condense into a cloud of vapor at the point where the vent system exits the building. Special consideration is recommended, before locating the vent termination near walkways, windows and building entrances.

Direct venting into dead spaces such as alleys, atriums, and inside corners can cause recirculation of ue gases. Recirculation of ue gases will cause sooting, premature failure of the heat exchanger, and icing of the combustion air intake during severe cold weather. To prevent the recirculation of ue gases, maintain as much distance as possible between the combustion air intake and the exhaust vent terminal. Due to large volumes of ue gases, multiple water heater applications also require additional distance between the intake and the exhaust terminals.

This water heater must be vented with Polypropylene, PVC/ CPVC or an UL approved AL 29-4C Stainless Steel venting material which are explained in the following pages. Vent sizing, installation and termination should be in accordance with this instruction manual.

All electrical power and gas must be turned off prior to any installation of the venting system.

GENERAL VENT INSTALLATION PROCEDURE

Prior to beginning the installation of the vent system, determine and obtain all parts required for the installation. Proper operation of the water heater and venting system is dependent upon use of all specied parts and installation techniques; both safety and proper performance of the system may suffer if instructions are not followed.

POLYPROPYLENE INSTALLATION:

All XWH water heaters are shipped with Polypropylene venting kits out of the factory. These kits are in separate cartons along with the water heater shipment. They must be assembled and installed on the water heater as shown in Figure 21 & Figure

22. Using Centrocerin is recommended as an assembly lube for venting. Application of Centrocerin resists movement between the vent legths and fittings. The vent pipes must also be properly supported. The kit also includes a PVC/CPVC adapter, which can be discarded and will only be required for PVC/CPVC vent installations. A condensate trap is also supplied with the venting kit and needs to be piped separately in the field.

PVC/CPVC INSTALLATION:

Installation must comply with local requirements and with the National Fuel Gas Code, ANSI Z223.1 for U.S. installations or CSA B149.1 for Canadian installations.

Refer to Table 12 on Page 36 for PVC/CPVC piping materials.

PVC/CPVC Installation requires the use of factory supplied PVC/CPVC adapters.

All PVC vent pipes must be glued, properly supported, and the exhaust must be pitched a minimum of a 1/4 inch per foot back to the water heater (to allow drainage of condensate).

This water heater requires a special venting system. Use only the vent materials, primer, and cement specified in this manual to make the vent connections. Failure to follow this warning could result in fire, personal injury, or death.

NOTE: Make sure that for PVC venting installation, the first 10 feet (3 m) of vent must be CPVC and the set point

temperature of the water heater must not exceed 200 °F.

STAINLESS STEEL INSTALLATION:

Installations must comply with applicable national, state, and local codes. Stainless steel vent systems must be listed as a UL1738 approved system for the United States and a ULC-S636 approved system for Canada.

The factory supplied polypropylene vent kit will not adapt to stainless steel installation. For using the water heater with stainless steel, contact factory or pre-order the unit with stainless steel kit.

Installation of the approved AL 29-4C stainless steel venting material should adhere to the stainless steel vent manufacturer’s installation instructions supplied with the vent system.

Refer to Table 13 and Table 14 on Page 36 for air intake and vent pipe sizes.

AIR INTAKE/VENT CONNECTIONS

1. Air Intake Adapter: Provides an inlet for combustion air

directly to the unit from outdoors.

2. Vent Outlet: Provides an outlet for combustion gases to outdoors.

VENTING SYSTEM

This water heater may be installed in six separate orientations depending on the require ments of the building and the appliance. The installer must decide which method is most appro priate for each installation. These orientations are:

1. Vertical Termination - vertical vent termi na tion through un-enclosed or en closed areas with roof penetration, see Figure 23 on Page 28.

2. Through-the-Wall Termination (TWT) - hori zontal vent termination directly through an outside wall, see Figure 24

on Page 28.

3. Horizontal Direct Vent - using TWT to exhaust ue prod ucts and PVC piping to bring combus tion air to the water heater from the outside. See Figure 25 on Page 29 and Figure 28 on Page 30.

4. Vertical Direct Vent - using a vertical vent termination to exhaust ue products and PVC piping to bring combustion air to the water heater from outside, see Figure 26 on Page 29 and Figure 27 on Page 30.

SUPPLIED VENT KIT:

PVC/CPVC ADAPTER

VENT PIPE

VENT CONDENSATE TRAP

PVC/CPVC ADAPTER

VENT PIPE

34 1/4"

FUSED ELBOW

FIGURE 21. POLYPROPYLENE INSTALLATION: SINGLE

HEAT EXCHANGER WATER HEATER

VENT CONDENSATE TRAP

FUSED ELBOW

FIGURE 22. POLYPROPYLENE INSTALLATION: DOUBLE

HEAT EXCHANGER WATER HEATER

AIR INLET PIPE MATERIALS

VENT AND AIR PIPE INSTALLATION

Make sure the air inlet pipe(s) are sealed. The acceptable air inlet pipe materials are:

• PVC/CPVC

• Polypropylene

The opening on the air intake box will readily accept PVC/CPVC pipes. If air intake is Polypropylene, an adapter (use the ones provided with exhaust kit) is required. Adapter part numbers:

SIZE PART NUMBERS

6" 324400-000

8" 324401-000

10" 324402-000

Seal all joints and seams of the air inlet pipe using either Aluminum Foil Duct Tape meeting UL Standard 723 or 181A-P or a high quality UL Listed silicone sealant. Do not install seams of vent pipe on the bottom of horizontal runs.

Secure all joints with a minimum of 3 sheet metal screws or pop rivets. Apply Aluminum Foil Duct Tape or silicone sealant to all screws or rivets installed in the vent pipe.

Make sure that the air inlet pipes are properly supported.

The PVC/CPVC or Polypropylene air inlet pipe must be cleaned and sealed with the pipe manufacturer’s recommended solvents and standard commercial pipe cement for the material used.

The PVC/CPVC or Polypropylene air inlet pipe should use a silicone sealant to ensure a proper seal at the water heater connection and the air intake adapter connection. Proper sealing of the air inlet pipe ensures that combustion air will be free of

contaminants and supplied in proper volume.

REQUIREMENTS FOR INSTALLATION IN CANADA

1. Installations must be made with a vent pipe system certied

to ULC-S636. IPEX is an approved vent manufacturer in Canada supplying vent material listed to ULC-S636.

2. The initial 3 feet (0.9 m) of plastic vent pipe from the water

heater ue outlet must be readily accessible for visual inspection.

3. The components of the certied vent system must not be

interchanged with other vent systems or unlisted pipe/ ttings.

1. Measure from the water heater level to vent. Refer to the Table 13 on Page 36 for the allowable lengths.

2. Prepare pipes to the required lengths and deburr the inside and outside of the pipe ends. Chamfer outside the pipe end to ensure even cement distribution when joining.

3. Clean all pipe ends and ttings using a clean dry rag. (Moisture will retard curing and dirt or grease will prevent adhesion.)

4. Dry t vent or air piping to ensure proper t before assembling any joint. The pipe should go a third to two-thirds into the tting to ensure proper sealing after cement is applied.

5. Priming and Cementing:

• Handle pipes and ttings carefully to prevent

contamination of surfaces.

• Apply an even coat of primer to the tting socket.

• Apply an even coat of primer to the pipe end to

approximately 1/2" beyond the socket depth.

• Apply a second primer coat to the tting socket.

• While primer is still wet, apply an even coat of approved

cement to the pipe equal to the depth of the tting socket.

• While primer is still wet, apply an even coat of approved

cement to the tting socket.

• Apply a second coat of cement to the pipe.

• While the cement is still wet, insert the pipe into the

tting, if possible twist the pipe a 1/4 turn as you insert it.

NOTE: If voids are present, sufcient cement was not applied and joint could be defective.

• Clear excess cement from the joint removing ring or

beads as it will needlessly soften the pipe.

When a sidewall or vertical rooftop combustion air supply system is disconnected for any reason, the air inlet pipe must be resealed to ensure that combustion air will be free of contaminants and supplied in proper volume.

Failure to properly seal all joints and seams may result in ue gas recirculation, spillage of ue products and carbon monoxide emissions causing severe personal injury or death.

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