540P Indoor Gas Tankless Water Heater

On-Demand Water Heater Installation Manual and Owner’s

Guide

SPECIFICATIONS

Model: 540P Indoor 540P Outdoor (AT-H3P-DV) (AT-H3P-OS)

Natural Gas Input (Operating Range): Min: 15,000 BTU/h, Max:
199,000 BTU/h

Propane Input (Operating Range): Min: 13,000 BTU/h, Max: 199,000
BTU/h

Gas Connection: 3/4 NPT

Water Connections: 3/4 NPT

Water Pressure* Natural gas Inlet Pressure: Min 4.0 psi (0.1
MPa), Max. 10.5 psi (2.61 kPa)

Propane Inlet Pressure: Min 8.0 psi (1.99 kPa), Max. 13.0 psi
(3.23 kPa)

Weight: 61.0 lbs. (27.7 kg)

Dimensions: H 22.4 x W 17.7 x D 10.7 inch (H 570 x W 450 x D 272
mm)

Ignition: Electric Ignition

Supply: 120 VAC / 60 Hz

Electric Consumption: With pump – 108.6 W / 1.34 A, Without pump
– 87.6 W / 1.10 A

Installation Manual

CONGRATULATIONS

Congratulations and thank you for choosing our tankless water
heater. Before use, we recommend that you read through this
installation manual carefully. Keep this manual for future
reference. If you need an additional manual, contact the
manufacturer or your local distributor. You may also download a
manual from our website. When you call, please tell us the product
name and the serial number of your unit written on the rating plate
of the water heater.

Owner’s Guide

OPERATING SAFETY

To ensure safe operation of the water heater, please follow
these guidelines:

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

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

MAINTENANCE AND SERVICE

To maintain the performance and efficiency of your water heater,
regular maintenance and service are required. Please refer to the
following sections for instructions:

INLET WATER FILTER CLEANING

Regularly clean the inlet water filter to prevent clogging and
ensure proper water flow. Follow these steps:

1. Turn off the water supply to the heater.

2. Locate the inlet water filter, usually located near the water
   inlet connection.

3. Remove the filter and clean it using water and a soft
   brush.

4. Inspect the filter for any damage and replace if
   necessary.

5. Reinstall the filter and turn on the water supply.

UNIT DRAINING & POWER OUTAGE (FREEZE PROTECTION)

In case of a power outage or if you need to drain the water
heater, follow these steps:

1. Turn off the power supply to the water heater.

2. Close the gas valve to stop the gas supply.

3. Attach a hose to the drain valve and place the other end in a
   suitable drain location.

4. Open the drain valve to allow the water to drain from the
   unit.

5. Once the unit is drained, close the drain valve and remove the
   hose.

6. Restore power supply and gas flow to the water heater.

MEASURING INLET GAS PRESSURE

It is important to measure the inlet gas pressure to ensure
proper operation of the water heater. Follow these steps:

1. Turn off the gas supply to the water heater.

2. Locate the gas inlet pressure tap on the gas valve.

3. Attach a manometer to the pressure tap.

4. Turn on the gas supply and observe the manometer reading.

5. The inlet gas pressure should be within the specified range
   mentioned in the specifications section.

6. If the pressure is not within the range, contact a qualified
   installer or service agency for adjustment.

TROUBLESHOOTING

If you encounter any issues with your water heater, refer to the
troubleshooting section in the manual for possible solutions. If
the problem persists, contact a qualified installer or service
agency for further assistance.

ERROR CODES

The water heater may display error codes in case of
malfunctions. Refer to the error codes section in the manual for a
list of codes and their corresponding meanings. If you need
assistance in resolving the error, contact a qualified installer or
service agency.

General

This section provides general information about error codes and
their troubleshooting steps.

Single unit installation

If you have a single unit installation, refer to this section
for specific error code information and troubleshooting steps.

How error codes display in an Easy-Link system

If you have an Easy-Link system installed, this section explains
how error codes are displayed and provides troubleshooting
steps.

Fault analysis

This section provides detailed fault analysis for each error
code. Use this information to diagnose and resolve the issue.

COMPONENTS DIAGRAM

Refer to the components diagram in the manual to familiarize
yourself with the various parts of the water heater.

PARTS LIST

The parts list section provides a comprehensive list of all the
parts included with the water heater. Use this list for reference
when ordering replacement parts or during maintenance.

OUTPUT TEMPERATURE CHART

The output temperature chart in the manual shows the temperature
range that can be achieved with the water heater based on the input
settings. Use this chart to set the desired water temperature.

FAQ

Q: Can I store flammable liquids near the water heater?

A: No, it is not safe to store or use gasoline or other
flammable vapors and liquids in the vicinity of this or any other
appliance.

Q: Who should perform the installation and service of the water

heater?

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

Q: How often should I clean the inlet water filter?

A: The inlet water filter should be cleaned regularly to prevent
clogging. It is recommended to clean it at least once every six
months or as needed depending on the water quality.

Q: What should I do in case of a power outage or if I need to

drain the water heater?

A: In case of a power outage or if you need to drain the water
heater, follow the instructions provided in the “UNIT DRAINING
& POWER OUTAGE (FREEZE PROTECTION)” section of the manual.

Q: How can I measure the inlet gas pressure?

A: To measure the inlet gas pressure, follow the instructions
provided in the “MEASURING INLET GAS PRESSURE” section of the
manual.

Q: What should I do if I encounter an error code on the water

heater?

A: If you encounter an error code, refer to the “ERROR CODES”
section of the manual for troubleshooting steps. If the problem
persists, contact a qualified installer or service agency.

On-Demand Water Heater Installation Manual and Owner’s Guide

RD
R
ANSI Z21.10.3 · CSA 4.3

Models
540P Indoor 540P Outdoor

If the information in these

instructions is not followed

exactly, a fire or explosion may

WARNING

result causing property damage, personal injury or death.

Gas Tankless Water HeaterTM
Suitable for combination potable water heating and space heating. Please refer to local codes for
space-heating compliance.

– Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance.
– WHAT TO DO IF YOU SMELL GAS · Do not try to light any appliance. · Do not touch any electric switch; do not use any phone in your building. · Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions. · If you cannot reach your gas supplier, call the fire department.
– Installation and service must be performed by a qualified installer, service agency or the gas supplier.

FEATURING · INTEGRATED RECIRCULATION PUMP · ENDLESS HOT WATER · ON-DEMAND USAGE · COMPACT, SPACE SAVING · ENERGY CONSERVATION · COMPUTERIZED SAFETY · NO PILOT LIGHT · Complies with SCAQMD Rule
1146.2 for natural gas NOx emissions of 14 ng/J or 20 ppm. · EASY-LINK SYSTEM

If you have any questions, please call or write to
USA: 500 Tennessee Waltz Parkway Ashland City, TN 37015
Toll Free: 1-877-737-2840
CANADA: 599 Hill Street West Fergus, ON N1M 2X1 1-888-479-8324

Keep this manual near the water heater for future reference whenever maintenance, adjustment or service is required.

Contents

CONTENTS
Installation Manual
SPECIFICATIONS ………………………………………4
INTRODUCTION………………………………………. 5 SAFETY GUIDELINES……………………………….6 SAFETY DEFINITION………………………………6 GENERAL……………………………………………… 6 INCORPORATED RECIRCULATION PUMP …….7 INSTALLATION …………………………………………8 CLEARANCES ………………………………………10 INCLUDED ACCESSORIES……………………..10 OPTIONAL ITEMS ………………………………..10 WARNING FOR INSTALLATIONS……………12 HIGH-ALTITUDE INSTALLATIONS ………….13 VENTING INSTRUCTIONS FOR INDOOR..14
Vent termination clearances ………………..15 Clearances for sidewall terminations …….16 Clearances for rooftop terminations ……..17 Combustion air supply…………………………18 Exhaust vent (ABS,PVC,CPVC, or polypropylene vent) ……………………………22 DIP switch settings for vent length (ABS,PVC,CPVC, or polypropylene vent)…23 Exhaust vent (Stainless steel vent) ………..27 DIP switch settings for vent length (Stainless steel vent)……………………………27 Common venting system ……………………..30 GAS SUPPLY AND GAS PIPE SIZING ………32 General ……………………………………………..32 Gas connections …………………………………32 Natural Gas supply piping…………………….33 Propane (LP) supply piping…………………..33 WATER CONNECTIONS ………………………..34 Recirculation pump mode ……………………35 Installation w/ dedicated return line……..35 Installation w/o recirculation ……………….36 Domestic and space heating ………………..36 Dual purpose water heating for the State of Massachusetts ………………….38 Pressure relief valve ……………………………39 CONDENSATE DRAIN …………………………..39 ELECTRICAL CONNECTIONS …………………41 TEMPERATURE REMOTE CONTROLLER …..41 Included accessories……………………………41 EASY-LINK SYSTEM …………………………………..43 Easy link connection procedures …………..43 INITIAL OPERATION ……………………………….45 Initial test run ……………………………………. 45

Owner’s Guide
OPERATING SAFETY ……………………………….48
NORMAL OPERATION ……………………………. 50 BUILT-IN CONTROLLER AND REMOTE CONTROLLER ………………50 GENERAL……………………………………………. 50 OUTLET WATER TEMPERATURE SETTING ……………………………………………..51 TEMPERATURE TABLE OF CONTROLLER .51 SETTING THE TIME ……………………………..52 PUMP OPERATION TIMERS………………….52 Setting pump timers ……………………………53 Selecting a pump timer ……………………….55 Display example………………………………….56 Pump operation test……………………………57 On-demand pump operation………………..57 ADDITIONAL FEATURES……………………….59 Information mode ………………………………59 Unit conversion mode …………………………59 SETTING TEMPERATURE ON THE PCB ……….60 FLOW …………………………………………………. 60 FREEZE PROTECTION SYSTEM …………….. 61
MAINTENANCE AND SERVICE ……………… 62 INLET WATER FILTER CLEANING ………………. 62 UNIT DRAINING & POWER OUTAGE (FREEZE PROTECTION) ………………………………………. 63 MEASURING INLET GAS PRESSURE ………….. 63
TROUBLESHOOTING………………………………. 64 ERROR CODES …………………………………….66 General ……………………………………………..66 Single unit installation ………………………… 66 How error codes display in an Easy-Link system………………………………………………. 67 Fault analysis ……………………………………..68
COMPONENTS DIAGRAM ……………………….70
PARTS LIST…………………………………………….74
OUTPUT TEMPERATURE CHART ……………… 76

2 Page

Installation Manual
Installation Manual
CONGRATULATIONS
Congratulations and thank you for choosing our tankless water heater. Before use, we recommend that you read through this installation manual carefully. Keep this manual for future reference. If you need an additional manual, contact the manufacturer or your local distributor. You may also download a manual from our website. When you call, please tell us the product name and the serial number of your unit written on the rating plate of the water heater.
3 Page

Installation Manual Specifications

SPECIFICATIONS

Model

540P Indoor 540P Outdoor (AT-H3P-DV) (AT-H3P-OS)

Natural Gas Input (Operating Range)

Propane Input (Operating Range)

Gas Connection
Water Connections
Water Pressure* Natural gas Inlet Pressure Propane Inlet Pressure Weight

Dimensions

Ignition

Supply

BTU/h BTU/h
psi (MPa) ” W.C. (kPa) ” W.C. (kPa)
lbs. (kg) inch mm
VAC / Hz

Min: 15,000 Max.: 199,000 Min: 13,000 Max.: 199,000
3/4″ NPT 3/4″ NPT 15 – 150 (0.1 – 1)
Min 4.0 (1.00) Max. 10.5 (2.61)
Min 8.0 (1.99) Max. 13.0 (3.23)
61.0 (27.7) H 22.4 x W 17.7 x D 10.7 H 570 x W 450 x D 272
Electric Ignition 120 / 60

Electric Consumption

Operation

With pump Without pump

W / A W / A

108.6 / 1.34 87.6 / 1.10

Standby

W / A

4.6 / 0.10

Freeze-Protection

W / A

192.3 / 1.63

Water heater Category**

Category IV

N/A

Maximum Pipe length***
(Hot Water supply line and Dedicated Return line)

Pipe Diameter

3/4″ ( 19 mm)
1/2″ ( 13 mm)

500 ft (152.4 m) 200 ft (61.0 m)

*40 psi or above is recommended for maximum flow.

**Water heater Category — water heaters of other than direct vent type, for outdoor installation, are divided into four

categories based on static pressure produced in the vent and flue loss.

Category IV – a water heater that operates with a positive vent static pressure and with a vent gas temperature that

may cause excessive condensate production in the vent.

***These are equivalent lengths that include head loss for elbows, tees, unions, etc. Refer to page 35 for additional

information available pipe on length. NOTE:

· Check the rating plate to ensure that this product matches your specifications.

· The manufacturer reserves the right to discontinue, or change at any time, specifications or designs

without notice and without incurring obligation.

4 Page

Installation Manual Introduction
INTRODUCTION
· This manual provides information necessary for the installation, operation, and maintenance of the water heater.
· The model description is listed on the rating plate which is attached to the side panel of the water heater.
· Please read all installation instructions completely before installing this product. · If you have any problems or questions regarding this equipment, consult the manufacturer or
its local representative. · This equipment is an on-demand, tankless water heater designed to efficiently supply endless
hot water when properly sized and installed. · This heater incorporates a recirculation pump for homes with an installed circulation system. · These high efficiency models have a built-in secondary heat exchanger that absorbs latent
heat from the exhaust gas. · The 540P Indoor model is only to be installed indoors. The 540P Outdoor model is only to be
installed outdoors. · The 540P Indoor model is categorized as Category IV when it isn’t installed in the direct vent
installation.
· The principle behind tankless water heaters is simple:

Exhaust thermistor

Secondary HX

Thermistor
Bypass valve
Thermistor Water control valve
Flow sensor Recirculation pump
Thermistor Thermistor

Burners

Primary HX
Gas valves Fan motor Computer board Condensate drain port

Hot water

Gas

Return line

Cold water

*This diagram illustrates tankless water heater design concepts only and does not accurately represent the water heater’s physical description.

1. A hot water fixture is turned on. 2. Water enters the heater. 3. The water flow sensor detects the water flow. 4. The computer initiates the fan motor and sends a signal to the igniter to create an ignition spark. 5. The gas ignites and flames appear within the burner chamber. 6. Water circulates through the heat exchanger and then gets hot. 7. Using thermistors to measure temperatures throughout the water heater, the computer modulates
the gas and water valves to ensure proper output water temperature. 8. When the fixture is turned off, the unit shuts down.

5 Page

SAFETY GUIDELINES
SAFETY DEFINITION

Installation Manual Safety Guidelines

Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury. DANGER
Indicates an imminently hazardous situation which, if not avoided, could result in death or serious injury. WARNING
Indicates an imminently hazardous situation which, if not avoided, could result in minor or moderate injury. CAUTION
NOTICE Indicates information considered important but not hazard related.
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or B149.1 Natural Gas, Propane Installation Code in Canada.
2. Properly ground the unit in accordance with all local codes or in the absence of local codes, with the National Electrical Codes: ANSI/NFPA 70 in the USA or CSA standard C22.1 Canadian Electrical Code Part 1 in Canada.
3. Carefully plan where you intend to install the water heater. Please ensure: · Your water heater will have enough combustible air and proper ventilation. · Locate your heater where water leakage will not damage surrounding areas. (Please refer to page 9.)
4. Check the rating plate for the correct GAS TYPE, GAS PRESSURE, WATER PRESSURE and ELECTRIC RATING. *If this unit does not match your requirements, do not install and consult with the manufacturer.
5. If any problem should occur, turn off all hot water taps and turn off the gas. Then call a trained technician or the Gas Company or the manufacturer.

6 Page

Installation Manual Installation

· Water temperatures over 125 °F (52 °C) can cause severe burns instantly or death from

scalding. The water temperature is set at 120 °F (50 °C) from the factory to minimize

any scalding risk. Before bathing or showering, always check the water temperature.

· To reduce the risk of scalding, install Thermostatic Mixing Valves (temperature limiting

valves) at each point of use.

· Do not store or use gasoline or other flammables, vapors, or liquids in the vicinity of

WARNING

·

this appliance. Do not reverse the water and/or gas connections as this will damage the gas valves

and can cause severe injury or death. Follow the diagram on page 36 when installing

your water heater.

· Should overheating occur or the gas supply fails to shut off, turn off the manual gas

control valve to the appliance.

· Do not use this appliance if any part has been in contact with or been immersed in

water. Immediately call a qualified installer or service agency to replace a flooded

water heater. Do not attempt to repair the unit. It must be replaced.

· Do not disconnect the electrical supply if the ambient temperature will drop below

freezing unless the water has been drained from the water heater. The Freeze

Protection System only works if the unit has electrical power. The warranty will not

be covered if the heat exchanger is damaged due to freezing. Refer to the section on

the Freeze Protection System on page 61 and Unit draining & power outage (Freeze

protection) on page 63 for more information.

· Failure to observe these warnings could result in severe personal injury or death.

INCORPORATED RECIRCULATION PUMP
This heater incorporates a recirculation pump for homes with an installed circulation system. The pump provides several useful features:
· The built-in controller and the remote controller (100276687/TM-RE43) offer two timer settings for pump operation: PUMP TIMER 1 and PUMP TIMER 2. The pump will operate during the times set for TIMER 1 and/or TIMER 2.
· The pump automatically turns on and off during set times depending on the set temperatures for pump operation. The set point temperature can be set by the built-in controller or the remote controller (100276687/TM-RE43).
· Instead of the timers, the pump can operate by pressing the PUMP button on the built-in controller or the remote controller (100276687/TM-RE43). A DIP switch must be turned on to use this control. (Refer to page 57.)
The maximum pipe length for the combined hot water supply line and return line is: · 1/2″ (13 mm) pipe: 200 ft (61.0 m) · 3/4″ (19 mm) pipe: 500 ft (152.4 m)
These are equivalent length that includes head loss for elbows, tees, unions, etc for smooth wall copper tube. Other water tube materials have different head loss characteristics. When other materials are used, the installer shall consult with the water tube manufacturer to conduct a head loss calculation to make sure the installed pump will flow at least 2 gpm. Please refer to the manufacturer’s specification sheet for pump head loss information. An additional pump may be necessary for circulation systems with longer equivalent pipe lengths.

7 Page

Installation Manual Installation
INSTALLATION
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or B149.1 Natural Gas, Propane Installation Code in Canada.
2. All gas water heaters require careful and correct installation to ensure safe and efficient operation. This manual must be followed exactly. Read the “Safety Guidelines” Section.
3. The manifold gas pressure is preset at the factory. It is computer controlled and should not need adjustment.
4. Maintain proper space for servicing. Install the unit so that it can be connected or removed easily. Refer to the “Clearances” Section on page 10 for proper clearances.
5. The water heater must be installed in a location where the proper amount of combustion air will be available to it at all times without obstructions, or the indoor heater must be direct vented. See pages 14 to 29.
6. Install the water heater so it is level (left-to-right & front-to-back) and plumb (vertically). 7. Electrical service to the water heater requires a means of disconnection. This will allow power to
the water heater to be shut off for servicing and safety purposes. 8. Do not install the unit where the exhaust vent is pointing into any opening in a building or where
the noise may disturb your neighbors. Make sure the vent termination meets the required clearance from any doorway or opening to prevent exhaust from entering a building. (Refer to pages 9, 12, 15 and 16.) Check local code requirements prior to installation. 9. Carefully plan the installation location of the heater and vent terminations. Contaminants such as aerosols, lint, and fine powders (including flour) can clog the air intake and reduce the operation of the fan. This, in turn, can cause improper combustion and reduce the life of the water heater. Regularly ensure that the area around the water heater, vent termination, and air intake is free of dust, debris, and other contaminants. In environments with a high level of contaminants (laundry facilities, hair salons, pet salons, chemical plants, commercial kitchens, etc.), direct venting is required. 10. The Indoor model is to be installed indoors only. This water hetaer equipped with a thermistor and hi-limit switch for the exhaust gas, detecting excess temperatures within the flue and enabling the unit to safely stop operations if needed. These components are always monitoring exhaust gas conditions in order to prevent heat damage to ABS, PVC, CPVC, or polypropylene (Plastic) venting if ABS, PVC, CPVC, or polypropylene is used. If the exhaust gas temperature exceeds 140 °F (60 °C), these components will enable the unit to safely stop operations. These components are not installed on the outdoor models since the exhaust vent is built-in.
· If the water heater is used as a direct-vent appliance, the unit requires 3″ or 4″ combustion air supply pipe. The intake pipe must be sealed airtight. Refer to pages 14 to 29 for more detail.
· Terminating the venting through a sidewall is recommended for the direct- vent system. · Running the exhaust vent and the intake pipe parallel is recommended. · Terminating the exhaust and intake on the same wall/surface is recommended. Terminating
in the same pressure zone allows for pressure balancing, which prevents nuisance shutdowns. · Only install the water heater in a heated area where below freezing temperatures cannot
occur. The warranty does not cover damage caused by freezing. · The water heater must be securely mounted to a wall or other suitable structure. · The venting system shall be installed in accordance with the water heater manufacturer’s and
venting system manufacturer’s instructions. 11. The Outdoor models must only be installed outdoors and only in an area with mild, temperate
climates. The Outdoor model shall be wall-mounted or mounted on a stand. Locate the Outdoor model in an open, unroofed area and maintain the following minimum clearances: There is a 3 in (76 mm) clearance from the left and right sides of the unit to combustible and non-combustible surfaces.
8 Page

Installation Manual Installation

· Installation and service must be performed by a qualified installer (for example, a licensed plumber or gas fitter). Otherwise, the warranty will be void.
· The installer (licensed professional) is responsible for the correct installation of the water heater and for compliance with all national, state/provincial, and local codes.
· The manufacturer does not recommend installing the water heater in a pit or location WARNING where gas and water can accumulate.
· Do not attach the gas line to the water heater until after the gas line system pressure test for leaks has been completed. See page 32 for additional information.
· Do not install or locate the vent terminal pointing toward any operating window, door, opening into a building or other area where people gather, where combustion gases could create a nuisance or hazard or cause property damage.
· Do not install the air intake next to any source of airborne debris, such as a clothes dryer, that can cause debris to be trapped inside the combustion chamber, unless the system is direct-vented.
· Do not install the unit where water, debris, or flammable vapors may get into the flue terminal or the air intake line.
· The manufacturer does not recommend installing the water heater in an attic due to safety issues. If you install the water heater in an attic: – Make sure the unit will have enough combustion air and proper ventilation. Failure to do so could lead to carbon monoxide poisoning or death. – Keep the area around the water heater clean. When dust collects on the flame sensor the water heater will shut down on an error code. – Place the unit where it will allow easy access for service and maintenance. – A drain pan, or other means of protection against water damage, is recommended to be installed under the water heater in case of leaks. See the NOTICE below.
· The water heater must be securely mounted to a wall or other suitable structure so that it is level (left-to-right & front-to-back) and plumb (vertically).
· Failure to observe these warnings could result in severe personal injury, death, and/or property damage.

NOTICE

· The warranty will not cover damage caused by water quality. – Only potable water can be used with this water heater. Do not introduce pool or spa water, or any chemically treated water into the water heater. – Water hardness levels must not exceed 7 grains per gallon (120 ppm) for single family domestic applications or more than 4 grains per gallon (70 ppm) for all other types of applications. Water hardness leads to scale formation and may affect/damage the water heater. Hard water scaling must be avoided or controlled by proper water treatment. – Water pH levels must be between 6.5 and 8.5. – Well water must be treated.
· The manufacturer recommends direct venting when the water heater is installed in beauty salons, dry cleaners or any other locations in which such chemicals are present in the air. Some chemicals used in beauty salons or dry cleaners may affect the flame sensor. In such cases, the water heater may not work properly.
· Although the water heater is designed to operate with minimal sound, the manufacturer does not recommend installing the unit on a wall adjacent to a bedroom, or a room that is intended for quiet study or meditation, etc.
· Locate your water heater close to a drain where water leakage will not do damage to surrounding areas. As with any water heating appliance, the potential for leakage at some time in the life of the product does exist. A drain pan, or other means of protection against water damage, is recommended to be installed under the water heater in case of leaks. In addition, you may install an active water leak detector with a shutoff valve which can turn off the water supply in the event of a leak. The manufacturer is not responsible for damage due to water leaks. If you install a drain pan under the unit, ensure that it will not restrict the combustion air flow.
9 Page

CLEARANCES

Installation Manual Installation
Top

WARNING

Maintain all clearances around the water heater. Failure to do so could create a fire hazard, potentially leading to death, serious injury, and/or property damage.

Side Front

Boom

Back Side

Model 540P Indoor*

Top

Bottom Front

Back

Sides

12 in

12 in

4 in** 0.5 in

3 in

(305 mm) (305 mm) (102 mm) (13 mm) (76 mm)

540P Outdoor

36 in

12 in

24 in

0.5 in

3 in

(914 mm) (305 mm) (610 mm) (13 mm) (76 mm)

*Standard indoor installations and direct-vent indoor installations have the same clearances. **24 inches (610 mm) recommended for maintenance.
INCLUDED ACCESSORIES

Check that these items below are included with the water heater.

Installation manual Temperature remote controller kit* Bird screen

and owner’s guide Outdoor model only

Indoor model only

Qty: 1 *Refer to pp. 10 and 38.

100276687 (TM-RE43)

OPTIONAL ITEMS

Model

Temperature remote controller

Pipe cover

3. Neutralizer kit

3″ PVC concentric termination

Recess box

6. Non-return valve

7

4″ PVC Adapter (for non-return valve)

540P Indoor

10 Page

Qty: 2 100282480
540P Outdoor

Installation Manual Installation

1. Temperature remote controller: 100276687 (TM-RE43) The temperature remote controller has the following features: · Adjusts set water temperature · Controls the pump operation · Works as a diagnostic tool · provides a concise error code whenever there is a
problem with the unit.
Refer to pages 50 to 59 for more information. See the Troubleshooting Section (pages 64 to 69) for information on possible error codes.

2. Pipe cover: 100112718 (TH-PC03)
The pipe cover protects the plumbing pipes to the water heater from unexpected adjustments. This pipe cover is fixed to the bottom of the water heater, which hides the plumbing and improves the visual aspects of the whole installation for the water heater.

3. Neutralizer kit: 100112159
The neutralizer assembly neutralizes the condensate (acidic water) that forms in the secondary heat exchanger of the water heater. It connects to the condensate drain port of the water heater by using connectors included with the neutralizer kit. (Refer to pages 39 and 40.)

4. 3″ PVC concentric termination: 100112163 Used when terminating direct-vent (sealed combustion) systems, with Indoor models that require a 3 intake and a 3 exhaust. This concentric termination provides the convenience of only having to make one penetration through a sidewall instead of two separate penetrations for the intake and exhaust piping. The termination includes a bird screen, restricting small animals, pests, and foreign objects from entering into the vent system.

5. Recess box: It allows for “clean” installations. The water heater fits inside the recess box, which hides and protects the whole water heater and plumbing. The recess box will fit between most wall studs.

Outdoor recess box for retrofit

applications -no flange

100298009

Outdoor recess box for new
construction applications 100306285 -with flange

6. Non-return valve for common venting : 100113130 7. 4″ PVC Adapter: 100113129

It is a required item for common venting system. It prevents the escape of combustion gas through non-operating appliances. (Refer to pages 30 and 31.)

This adapter transitions from the Non-return valve outlet to 4″ schedule 40 PVC pipe.

11 Page

Installation Manual Installation
WARNING FOR INSTALLATIONS

FOR YOUR SAFETY, READ BEFORE INSTALLATION:

Do not install the heater where water, debris or flammable vapors may get into the flue terminal. This may cause damage to the heater and void the warranty.

Do not have the vent terminal pointing toward any opening into a building. Do not locate your heater in a pit or location where gas and water can accumulate.

Prohibited

Prohibited

Ensure that you meet the minimum clearances shown below for a direct vent termination:

Ensure that you meet the minimum clearances shown below for Outdoor vent termination:

USA: 1 ft (30 cm) min. Canada: 3 ft (91 cm) min.

USA: 1 ft (30 cm) min. Canada: 3 ft (91 cm) min.

USA: 1 ft (30 cm) min. Canada: 3 ft (91 cm) min.

USA: 1 ft (30 cm) above grade and above ancipated snow level Canada: 1 ft (30 cm) above grade
Ancipated snow level

4 ft min.

4 ft min. 4 ft min.

Locate the outdoor water heater so it’s vent termi-
nal meets the following clearances. Locate the vent
terminal of an indoor heater to meet the following
clearances: 2 ft (61 cm) from an inside corner 2 ft (61 cm) from an outside corner 3 ft (91 cm) below a soffit/overhang

Do not install next to a dryer or any source of airborne debris that can be trapped inside the combustion chamber, unless the system is direct-vented.

Outside corner
2 ft (61 cm)

3 ft (91 cm)

Inside corner

2 ft (61 cm)

12 Page

Installation Manual Installation

HIGH-ALTITUDE INSTALLATIONS

WARNING

· To adjust high altitude settings, adjust only the No. 2, No. 3, and No. 4 DIP switches in the MIDDLE bank of DIP switches. (See below.) DO NOT adjust the other DIP switches.
· Turn off the power supply to the water heater before changing the DIP switch settings.
· Failure to observe these warnings could lead to carbon monoxide poisoning or death.

Check the elevation where your water heater is installed. Set DIP switches shown in the table below depending on the altitude.
Indoor model

Altitude DIP switches

0 to 2,000 ft 2,001 to

3,001 to

5,001 to

7,501 to

(0 to 610 m) 3,000 ft

5,000 ft

7,500 ft

10,100 ft

(DEFAULT) (611 to 914 m) (915 to 1,524 m) (1,525to2,286m) (2,287to3,078m)

ON 1234 56
ON 1234 56
ON 1234 56
ON 1234 56
ON 1234 56

Middle bank of DIP switches

No. 2 : OFF No. 3 : OFF No. 4 : OFF

No. 2 : OFF No. 3 : ON No. 4 : OFF

No. 2 : OFF No. 3 : OFF No. 4 : ON

No. 2 : OFF No. 3 : ON No. 4 : ON

No. 2 : ON No. 3 : ON No. 4 : ON

Outdoor model
Altitude DIP switches
Middle bank of DIP switches

ON 1234 56
ON 1234 56
ON 1234 56

0 to 2,000 ft (0 to 610 m)
(DEFAULT)
No. 2 : OFF No. 3 : OFF No. 4 : OFF

2,001 to

4,001 to

4,000 ft

6,000 ft

(611 to 1,219 m) (1,220to1,829m)

No. 2 : OFF No. 3 : OFF No. 4 : ON

No. 2 : ON No. 3 : OFF No. 4 : ON

Installation altitude
The maximum certified or allowable installed altitude is 10,100 ft (3,078 m) for indoor model and 6,000 ft (1,829 m) for outdoor model.

NOTE: The dark squares indicate the correct DIP switch positions.

Upper bank of DIP switches Middle bank of DIP switches
Lower bank of DIP switches

13 Page

Installation Manual Installation
VENTING INSTRUCTIONS FOR INDOOR
· Improper venting of this appliance can result in excessive levels of carbon monoxide which can result in severe personal injury or death.
· Improper installation can cause nausea or asphyxiation, severe injury or death from carbon monoxide and flue gases poisoning. Improper installation will void product
WARNING warranty. · When installing the vent system, all applicable national and local codes must be followed. If you install thimbles, fire stops or other protective devices and they penetrate any combustible or noncombustible construction, be sure to follow all applicable national and local codes.
The Indoor model must be vented in accordance with the section “Venting of Equipment” of the current edition of the National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the United States and/or Section 8 of the B149.1 Natural Gas and Propane Installation Code in Canada, as well as applicable local building codes. The use of venting materials approved for Category III/IV appliances is recommended whenever possible. However, the Indoor model may also be vented with plastic pipe materials such as ABS, PVC (solid core), CPVC (solid core), or polypropylene. For details, please refer to the Exhaust Vent (ABS, PVC, CPVC, or Polypropylene Vent) Section on page 22. Vent installations in Canada which utilize plastic vent systems must use venting that complies with ULC S636.
General rules for venting water heaters: · Place the water heater as close as possible to the vent termination. · The vent collar of the water heater must be fastened directly to an unobstructed vent pipe. · Do not weld the vent pipe to the water heater’s vent collar. · Do not cut or alter the vent collar of the unit. · The vent must be easily removable from the top of the water heater for normal service and inspection of the unit. · The water heater vent must not be connected to any other gas appliance or vent stack except an approved common-venting system. Refer to pages 30 and 31. · Avoid using an oversized vent pipe or using extremely long runs of the pipe unless it is part of an approved common vent system. · Air supply pipe can be made of ABS, PVC (solid core), CPVC (solid core), polypropylene, corrugated stainless steel, or Category lll/IV stainless steel. Regarding exhaust pipe, refer to pages 22 to 29. · Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in nonmetallic venting systems is prohibited. Covering non-metallic vent pipe and fittings with thermal insulation is prohibited. · Sidewall venting is recommended for the Indoor model. Vertical venting (roof termination) is acceptable. · Slope horizontal venting sections 1/4″ upwards for every 12″ (300 mm) toward the termination or according to local and state codes, or in the absence of local or state codes, the current edition of the National Fuel Gas Code, ANSI Z223.1 (NFPA 54). · The manufacturer recommends running the exhaust vent and the intake pipe as parallel as possible. · For rooftop venting, a rain cap or other form of termination that prevents rain water from entering into the water heater must be installed. · Do not terminate vent into a chimney. If the vent must go through the chimney, the vent must run all the way through the chimney with approved vent pipe. · The water heater shall not be connected to a chimney flue serving a separate appliance, designed to burn solid fuel. · When an existing Category I appliance is removed or replaced, the original venting system may no longer be sized to properly vent the attached water heater. An improperly sized venting system may cause formation of condensate, leakage, and spillage and so on.
General rules for vent terminations: · Avoid locating the water heater vent termination near any air intake devices. These fans can pick up the exhaust flue products from the water heater and return them to the building. This can create a health hazard. · Locate the vent termination so that it cannot be blocked by any debris, at any time. Most codes require that the termination be at least 12 in (305 mm) above grade and anticipated snow level, but the installer may determine if it should be higher depending on the job site condition and applicable codes. · A proper sidewall termination is recommended when the water heater is vented through a sidewall. · Regarding the clearances from the exhaust termination to the air inlet or opening, refer to pages 12, 15 and 16.
14 Page

D E

-Vent termination clearances-

Installation Manual Installation

Inside corner detail
G
V
A

Legend: V = Vent terminal X = Air supply inlet = Area where terminal is not permied
H

L

B

C

V

Fixed closed

Operable

FV

B

B

B Fixed

V

V Operable closed

B X

V

B A

J

I

15

M

X

V

K

Regulator vent outlet In the event no regulator is present, H and I can be disregarded

Canada Installations1

Direct vent and other than direct vent

A Clearance above grade, veranda, porch, deck, or balcony

1 ft (30 cm)

Direct vent

US Installations2 Other than direct vent 1 ft (30 cm)

B Clearance to window or door that may be opened

3 ft (91 cm)

1 ft (30 cm)

4 ft (1.2 m) below or to side of opening;
1 ft (30 cm) above opening

C Clearance to permanently closed window

0

0

0

Vertical clearance to ventilated soffit located above D the terminal within a horizontal distance of 2 ft (61
cm) from the center line of the terminal

3 ft (91 cm)

3 ft (91 cm)

3 ft (91 cm)

E Clearance to unventilated soffit

3 ft (91 cm)

3 ft (91 cm)

3 ft (91 cm)

F Clearance to outside corner

2 ft (61 cm)

2 ft (61 cm)

2 ft (61 cm)

G Clearance to inside corner

2 ft (61 cm)

2 ft (61 cm)

2 ft (61 cm)

H

Clearance to each side of center line extended above meter/regulator assembly

3 ft (91 cm) within a height of 15ft(4.6m)

I Clearance to service regulator vent outlet

3 ft (91 cm)

Clearance to non-mechanical air supply inlet to J a building or the combustion air inlet to any other
appliance.
K Clearance to mechanical air supply inlet

3 ft (91 cm) 6 ft (183 cm)

1 ft (30 cm)

4 ft (1.2 m) below or to side of opening;
1 ft (30 cm) above opening

3 ft (91 cm) above if within 10 ft (3 m) horizontally.

L

Clearance above paved sidewalk or paved driveway located on public property

7 ft (213 cm)**

7 ft (213 cm)

7 ft (213 cm)

M Clearance under veranda, porch deck, or balcony

1 ft (30 cm)***

1 ft (30 cm)***

1 ft (30 cm)***

*Clearance in accordance with local installation codes and the requirements of the gas supplier.

**A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves

both dwellings.

***Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.

The vent for condensing water heaters shall not terminate:

· over public walkways; or

· near soffit vents or crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or cause property damage; or

· where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other

equipment.

Notes:

1. In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code

2. In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code

3. If locally adopted installation codes specify clearances different than those illustrated, then the most stringent clearance shall prevail.

4. Blocking air supply and exhaust vent by snow may cause incomplete combustion and an appliance failure. Install the termination by

providing sufficient clearance from anticipated snow line in accordance with local code or manufacture’s instructions and make sure

there in no blockage.

5. Provide an appropriate clearance between a vent termination and a building to prevent degradation to building materials caused by

flue gases.

6. Water heaters installed outdoors follow the Other Than Direct Vent clearances.

15 Page

Installation Manual Installation
-Clearances for sidewall terminations-

Improper installation can result in carbon monoxide poisoning or death. Follow all local
and national codes in regards to proper termination clearances. In the absence of such
codes, the clearances below can be used as guidelines. Local codes supersede these WARNING guidelines.

(30m15ifmnt.m) (61m02imfnt.m)

TerEmxAhinnaauttisictoinpat(e30dm51Simfntn.mo)w

level cInosrindeer

Multiple Sidewall Terminations An exhaust termination must be at least 1 ft (305 mm) away from another exhaust termination. An exhaust termination must also be at least 2 ft (610 mm) away from an inside corner. (If the adjacent wall is less than 2 ft (610 mm) of length, the minimum required distance away from the inside corner will be equal to the length of that adjacent wall.)

2 ft (610 mm) min.

Exhaust termination

Combined intake and exhaust termination

2 ft

1 ft (305 mm)

(610 mm) min.

min.

1 ft

(305 mm)

min. Anticipated Snow

level Inside

corner

Multiple DV Sidewall Terminations
A direct vent (DV) termination must be at least 1 ft (305 mm) away from other direct vent terminations. A direct vent termination must also be at least 2 ft (610 mm) away from an inside corner. (If the adjacent wall is less than 2 ft (610 mm) of length, the minimum required distance away from the inside corner will be equal to the length of that adjacent wall.)

<Case 1> Exhaust

For direct vent sidewall terminations that use two separate penetrations for the intake and exhaust, keep the termination clearances shown in the diagrams on the right.

Intake
1 ft (305 mm) min.

Exhaust Intake
0.5 ft (159 mm) min.

Exhaust and/or direct vent sidewall terminations should be at least 2 ft (610 mm) away from an opposite surface/wall. Do not place the termination directly in front of an opening into a building.
0.5 ft (159 mm)
min.

<Case 2> Exhaust
1 ft (305 mm) min. Intake

Exhaust Intake
0.5 ft (159 mm) min.

16 Page

Installation Manual Installation
-Clearances for rooftop terminations-

Follow all local and national codes in regards to proper termination clearances. In the absence of such codes, the clearances below must be met. Local codes supersede these WARNING clearances. Failure to observe this warning may result in severe personal injury or death.

NOTICE

Canadian requirements differ from the guidelines in this section. In Canada, follow the requirements of B149.1 (Natural Gas and Propane Installation Code, current edition) as well as local and provincial codes. Contact your local code enforcement agency for direction.

Angled roof termination

2 ft (610 mm) min.
Exhaust

1 ft (305 mm)
min.

Intake

1 ft (305 mm)
min.

1 ft (305 mm)
min.

Flat roof termination

Intake

3 ft (914 mm) min.

Exhaust

1 ft (305 mm)
min.

1 ft (305 mm)
min.

Anticipated snow level

Anticipated snow level

Multiple angled roof terminations

Multiple flat roof terminations

1 ft (305 mm)
min.
1 ft (305 mm)
min.
Anticipated snow level

Exhaust
3 ft (914 mm)
min.

1 ft (305 mm)

Exhaust

min.

1 ft (305 mm)
min.

2 ft (610 mm)
min.

Exhaust

Exhaust

Intake
1 ft (305 mm)
min.

Intake

2 ft (610 mm)
min.

1 ft (305 mm)
min.

1 ft (305 mm)
min.

3 ft (914 mm)
min.

Intake

Ancipated snow level

Intake

· ·
WARNING · ·

Exhaust terminations must be at least 1 ft (305 mm) away from any obstructions. Minimum spacing between multiple terminals:
· intake terminals: 1 ft (305 mm) spacing between each · exhaust terminals: 1 ft (305 mm) spacing between each The exhaust termination must be a horizontal distance of at least 2 ft (610 mm) from a wall or surface unless specified differently by local code. Failure to observe this warning may result in severe personal injury or death.

17 Page

-Combustion air supply-

Installation Manual Installation

WARNING

This gas water heater requires an adequate source of clean air for combustion and ventilation. Without sufficient air, your water heater may not operate properly and may emit excessive and abnormal amounts of carbon monoxide which may result in carbon monoxide poisoning or death.

· The guidelines in this section apply to installations within the United States. All

NOTICE

U.S. installations must conform to the National Fuel Gas Code, ANSI Z223.1/NFPA 54 (current edition) and local codes.

· Canadian requirements differ from the guidelines in this section. In Canada, follow the requirements of B149.1 (Natural Gas and Propane Installation Code, current edition) as well as local and provincial codes. Contact your local code enforcement agency for direction.

Before installing the water heater, you must determine the amount of air needed to supply this water heater and any other gas appliances in the same area and provide adequate air for combuson and venlaon. Consult a qualified person if you’re unsure of the proper way to supply air to your water heater.
Check for Chemicals: Air for combuson and venlaon must be clean and free of corrosive chemicals. If corrosive chemicals, such as sulfur, fluorine, or chlorine are present, the water heater must be direct vented. Failure due to these corrosive chemicals is not covered by the warranty.
WARNING! In all cases, ensure that corrosive chemicals are not present at the air intake. Presence of such chemicals at the air intake could result in death, personal injury, or property damage. Examples of locaons that require outside air due to chemicals include:
· Beauty salons
· Photo processing labs
· Indoor pools · Laundry, hobby, or craft rooms · Chemical storage areas
· Restaurants
Products such as aerosol sprays, detergents, bleaches, cleaning solvents, gasoline, air fresheners, paint and varnish removers, and refrigerants should not be stored or used near the water heater.
Does your installation space have sufficient combustion air?
Venlaon with outside air is recommended for all installaons. Even if the water heater is installed in a large, open room inside the house, outdoor air is usually needed because modern homes are very ghtly sealed and often do not supply enough air to the water heater. However, when installed in a large indoor space, it may be possible to provide enough air without outside venlaon. If you are unsure if your installaon locaon has enough venlaon, contact your local gas ulity company or code officials for a safety inspecon or direct vent the water heater. The following instrucons will help determine if it may be possible to install the water heater without outside venlaon.
Calculate total BTU/h rang of all appliances. To calculate the combuson air and venlaon required, add up the total BTU/h rangs of all gas burning appliances (e.g., water heaters, furnaces, clothes dryers) in the same area. Do not include appliances that are direct vented. Refer to the following example.
18 Page

Installation Manual Installation

Your water heater’s BTU/h rating is on the rating plate. The BTU/h ratings should be on the other appliances’ rating plates. If you have trouble determining the BTU/h ratings, contact the manufacturer or have a qualified person determine the ventilation requirements.
NOTICE: If you are replacing your old water heater with one that has a higher BTU/h rang, the amount of venlaon required may be greater.

Example:

Gas Burning Appliance
Gas Water Heater Furnace Dryer

BTU/h Rang
199,000 75,000 20,000

Your appliances:

Gas Burning Appliance Gas Water Heater

BTU/h Rang

Total

294,000

Total

Calculate the air volume of the room Air requirements depend on the size of the room.
Room Volume (ft3) = Floor Area (ft2) X Ceiling Height (ft) If there are large objects in the room (e.g., refrigerator, furnace, car), subtract their volume from the volume of the room to get a beer esmate of the air available.
Air Volume = Room Volume – Object Volume
NOTE: Adjoining rooms with permanently opened doorways can be counted as part of the calculaon.
Calculate required air volume
A water heater installed in an unconfined attic, garage, or space requires that the space be at least 50 ft3 (1.42 m3) per 1,000 BTU/h of the total input for all gas burning appliances in the same area.
Required Air Volume (ft3) =Total Appliance Energy Rang (btu/h) X 50 ft3 / 1000 (btu/h) Example:
(294,000 / 1000) x 50 = 14,700 ft3
If the air volume of the room is less than the required air volume, you must direct vent the water heater or provide permanent outside air openings that draw in sufficient air. Go to “Install with outside venlaon” if you want to provide combuson air with outside venlaon.
If the air volume of the room is greater than the required air volume, it may be possible to install the water heater without outside venlaon. However, be sure to consider the effects of exhaust fans. Exhaust fans can affect the amount of combuson air that is available in your home. Appliances such as furnaces, whole house fans, and clothes dryers draw air out of your home. If they draw air out faster than it can be replaced, your water heater may not have enough oxygen to fire properly. Back-drafting may also result, which is when negave air pressure pulls air backwards through chimneys or appliance vents. These events can cause unsasfactory water heater performance. The best soluon is to direct vent the water heater or install an adequate number of make-up air vents. (See “Install with outside venlaon”.) For more informaon, consult a qualified technician or your local gas ulity.
Install with outside ventilation
Venlaon with outside air is recommended, and, for most installaons, is needed. There may be exisng venlaon that is adequate, or you may need to add more venlaon.
Supplying outside air to the water heater typically requires two openings. One opening must be within 12 in (305 mm) from the floor and the second opening must be within 12 in (305 mm) from the ceiling. Although a single opening is not preferred, you may use a single opening to outside air if the minimum free area is sized according to Table 1. Two openings must be used when venlang with air from another room. The outside air can be taken from a crawl space or attic open to the outdoors and adequately venlated. You may use vercal or horizontal ducts.
19 Page

Installation Manual Installation

Determine type of ventilation
There are several types of venlaon that can be used. The various opons are listed below. See also the illustraons on the next page.
1. Direct to outdoors
2. Vercal ducts 3. Horizontal ducts
4. Single opening (not recommended; must be at least 100 in2 (645 cm2) . Not appropriate for confined spaces smaller than 50 ft3 (1.42 m3) per 1,000 BTU/h or when getting air from another room.)
5. From a larger room inside the house (not recommended ­ refer to “Calculate the air volume of the room”
above to determine if the combined volume of the rooms may be adequate).
Determine minimum free area required for each vent opening
The size of the vent openings depends on the total BTU/h rang of all appliances in the space (use your calculaon from “Before beginning”) and the type of vent used. Table 1 provides the minimum free area for each vent opening depending on the type of venlaon.
Calculate minimum size of vent openings and ducts
The vent cross-seconal area needed to provide the free area depends on the covering on the vent openings. Typical vents use louvers or grilles to protect the opening. The louver or grill itself blocks some of the free area, so the opening may need to be larger to meet the minimum free area requirements. Use the following formula to calculate the required cross-seconal area:
Cross-seconal area = minimum free area required ÷ percent free area of covering (in decimals ­ e.g., 60 % = 0.6) For example, an installaon area that requires openings with 100 in2 (645 cm2) of free area would need 134 in2 (865 cm2) openings if using metal louvers rated at 75% free area (100 in2 ÷ 0.75 = 134 in2). If you do not know the % free area for your louver or grill, use the following values:
· For wood louvers or grilles: 25% · For metal louvers or grilles: 75% Follow these rules to ensure that vents and ducts provide adequate air flow: · Each vent opening must be no smaller than 100 in2 (645 cm2). · Ducts must have the same cross-seconal area as free area of the opening. · Rectangular ducts must have a minimum dimension of no less than 3 in (76 mm). · All screens must have mesh ¼” or larger. · Moveable louvers must be locked open or interconnected with the equipment so that they open automa-
cally during operaon. · Keep louvers and grills clean and free of debris or other obstrucons.
Check that air source is clean and free of chemicals
Air for combuson and venlaon must be clean and free of corrosive or flammable chemicals. A failure due to corrosive chemicals in the air is not covered by the warranty. Combuson air must be free of acid-forming chemicals such as sulfur, fluorine, and chlorine. Be sure that air at the vent inlets is free of such chemicals.

Table 1

Minimum Free Area of Permanent Openings for Venlaon and Combuson Air Supply ­ Air from outdoor or

indoor spaces.

Based on the total BTU/h input rang for all gas burning appliances within a confined space.

Opening Source

Minimum Free Area

Direct to outdoors*

1 in2 (6.5 cm2) per 4,000 BTU/hr (see Figure 1, 2)

Vercal ducts

1 in2 (6.5 cm2) per 4,000 BTU/hr (see Figure 3)

Horizontal ducts

1 in2 (6.5 cm2) per 2,000 BTU/hr (see Figure 4)

Single Opening

1 in2 (6.5 cm2) per 3,000 BTU/hr (see Figure 5)

Two permanent openings

1 in2 (6.5 cm2) per 1,000 Btu/hr (see Figure 6)

to another room**

Opening: 100 in2 (645 cm2) Min

Minimum dimension of air openings:

no less than 3 in (76 mm)

*These openings connect directly with the outdoors through a venlated attic, a venlated crawl space, or through

an outside wall.

**United States: For direcon on combining spaces in different stories within the structure, refer to the current edi-

on of the Naonal Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada, contact your local code enforcement agency for

direcon.

See graphics on next page.

20 Page

Combuson air supply opons

Confined Space

Gable vent to outdoors
Install above insulation
Outlet air to attic 1 in2 (6.5 cm2) per 4,000 btu/h

Alternate Air Inlet

Inlet air from the crawl space

1 in2 (6.5 cm2) per 4,000 btu/h

Open foundation vent

Figure 1 – Direct to outdoors openings

Confined Space

Gable vent to outdoors Install above insulation

12″ (305 mm) maximum

Outlet air to attic 1 in2(6.5 cm2) per 4,000 btu/h Inlet air duct 1 in2 (6.5 cm2) per 4,000 btu/h

Figure 3 – Vercal duct openings

Installation Manual Installation

12″ (305 mm) maximum

Two permanent Openings
1 in2 (6.5 cm2) per 4,000 btu/h

Confined Space 12″ (305 mm) maximum

Figure 2 – Direct to outdoors openings Two permanent openings

Confined Space

1 in2 (6.5 cm2) per 2,000 btu/h
Outlet Outdoor Air Ducts
Inlet

1 in2 (6.5 cm2) per 2,000 btu/h
Figure 4 – Horizontal duct openings

CSpoancfiened

Alternative Opening Location
1 in2 (6.5 cm2) per 3,000 btu/h

12″ (305 mm) maximum
Confined Space

Two permanent Openings

1 in2 (6.5 cm2) per 1,000 btu/h

12″ (305 mm) maximum

Figure 5 – Single opening

Figure 6 – Two permanent openings
21 Page

Installation Manual Installation

-Exhaust vent (ABS, PVC, CPVC, or polypropylene vent)-

The Indoor model can be vented with ABS, PVC, CPVC, or polypropylene (temperature rated up to 149 °F). Vent material certified to ULC S636 standards is recommended in the USA. In Canada, plastic venting must be certified to ULC S636 standards.

Item

Material

Schedule 40 PVC

Exhaust pipe and Fittings

PVC-DWV Schedule 40 CPVC Schedule 40 ABS-DWV

Polypropylene

PVC

Pipe Cement/Primer

CPVC

United States ANSI/ASTM D1785 ANSI/ASTM D2665 ANSI/ASTM F441 ANSI/ASTM D2661
UL-1738 ANSI/ASTM D2564 ANSI/ASTM F493

Canada
ULC S636 Certified Materials Only

ABS

ANSI/ASTM D2235

Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in non-metallic venting systems is prohibited. Covering non-metallic vent pipe and fittings with thermal insulation is prohibited.

· The maximum length of exhaust vent piping must not exceed 70 ft (21.3 m) for 3″ (76 mm) venting, which depends on the elevation where the water heater is installed, and 100 ft (30.5 m) for 4″ (102 mm) venting (deducting 5 ft (1.5 m) for each elbow used in the venting system). Do not use more than 5 elbows. See the table below.
· When the horizontal vent run exceeds 5 ft (1.5 m), support the vent run at 3 ft (0.9 m) intervals with overhead hangers.

Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length*

3 in

5

70 ft (21.3 m)

4 in

5

100 ft (30.5 m)

*For each elbow added, deduct 5 ft (1.5 m) from max. vent length.

Max. Vertical or Horizontal (Total) Vent Length

No. of Elbows*

0 to 3,000 ft (0 to 914 m)

3″ venting
3,001 to 6,000 ft 6,001 to 10,100 ft (915 to 1,829 m) (1,830 to 3,078 m)

0

70 ft (21.3 m) 40 ft (12.2 m) 25 ft (7.6 m)

1

65 ft (19.8 m) 35 ft (10.7 m) 20 ft (6.1 m)

2

60 ft (18.3 m) 30 ft (9.1 m)

15 ft (4.6 m)

3

55 ft (16.8 m) 25 ft (7.6 m)

10 ft (3.0 m)

4

50 ft (15.2 m) 20 ft (6.1 m)

N/A

5

45 ft (13.7 m)

N/A

N/A

Excludes vent terminators, termination elbows, or rain caps.

4″ venting
0 to 10,100 ft (0 to 3,078 m) 100 ft (30.5 m) 95 ft (29.0 m) 90 ft (27.4 m) 85 ft (25.9 m) 80 ft (24.4 m) 75 ft (22.9 m)

For details on the vent connection, refer to pages 24 to 25. *For each elbow added, deduct 5 ft (1.5 m) from max. vent length.

22 Page

Installation Manual Installation

-DIP switch settings for vent length-
Typical installaons using PVC, CPVC, ABS, or polypropylene vent

·
· WARNING
·

To adjust vent length, adjust only the No. 3 and No. 4 DIP switches in the LOWER bank of DIP switches. (See below.) DO NOT adjust the other DIP switches. Turn off the power supply to the water heater before changing the DIP switch settings. Failure to observe these warnings could lead to carbon monoxide poisoning or death.

<Two-pipe, direct-vent installaon>

Horizontal Installaon

Vercal Installaon

Wall Hanger
Hanger

Roof Roof
flashing

Fire stop
Connect between exhaust vent collar and piping. See the instrucons on the next page.
For details on the vent components, refer to the vent manufacturer’s instructions.

Set DIP switches shown in the table below depending on the vent diameter and length.

DIP switch settings : Two-pipe, Direct vent installations

Vent diameter

3″ venting*

4″ venting

Vent 5 to 20 ft

5 to 50 ft

DIP

length

(1.5 to 6.1 m)

21 to 40 ft (6.2 to 12.2 m)

41 to 70 ft (12.3 to 21.3 m)

(1.5 to 15.2 m)

51 to 100 ft (15.3 to 30.5 m)

switches

(DEFAULT)

(DEFAULT)

Lower bank of DIP switches

ON 1234 5678
ON 1234 5678
ON 1234 5678
ON 1234 5678
ON 1234 5678

Lower bank of
DIP switches
No. 3 : O N No. 4 : OFF

No. 3 : OFF No. 4 : OFF

No. 3 : O N No. 4 : O N

No. 3 : O N No. 4 : OFF

No. 3 : OFF No. 4 : OFF

*PVC concentric termination (100112163) installation is applied to the DIP switch settings of 3″ venting. (Refer to page 11.)
23 Page

Installation Manual Installation
<How to install intake and exhaust venting (two-pipe, direct-vent) with the indoor model> 3″ vent connecon for PVC/CPVC venng only 4″ vent connecon for PVC/CPVC venng only

3″ straight pipe

3″ straight pipe

Intake vent collar with 3″ adapter* (Female)

Exhaust vent collar with 3″ adapter* (Female)

4″straight pipe

4″ straight pipe 3″ x 4″ increaser

· PVC adapter will accept 3″ straight pipe.
3″ vent connecon for other venng without 3″ PVC adapter

3″ x 4″ increaser
3″straight pipe no more than 12″ (305 mm)
Intake vent collar with

3″ straight pipe no more than 12″ (305 mm)
Exhaust vent collar with 3″ adapter* (Female)

3″ adapter* (Female)

3″ adapter*

3″ adapter*

Intake vent collar

(Female)

Exhaust vent collar

Screws

(Female)

1. Insert no more than 12″ (305 mm) of 3″ straight

pipe into the exhaust/intake vent collar with 3″

1. Remove each screw from 3″ adapter to detach the

adapter.

adapters from each vent collar.

2. Connect 3″ x 4″ increasers to straight pipes.

3. Connect 4″ straight pipes to the increasers.

3″ straight pipe

3″ straight pipe

Intake vent collar (Female)

Exhaust vent collar (Female)

NOTICE *3″ PVC adapters are not

2. Connect 3″ straight pipes directly on the exhaust and intake vent collar of the water heater.

approved for use in Canada.