Bosch GWH 2400 ES NG, GWH 2400 ES LP User Manual

MODEL GWH 2400 ES NG and GWH 2400 ES LP INDOOR MODEL

Temperature Modulated with Electronic Ignition Suitable for heating potable water only Not approved for space heating purposes

(Intended for variable flow applications)

GWH 2400 ES NG - Natural Gas GWH 2400 ES LP - Liquefied Petroleum (LP) Gas

Warning: If the information in this manual is not

followed exactly, a fire or explosion may result causing property damage, personal injury or death. Do not store or use gasoline or other flammable vapor and liquids in the vicinity of this or any other appliance.

Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information consult a qualified installer, service agency or the gas supplier. In the Commonwealth of Massachusetts this product must be installed by a licensed plumber or gas fitter.

Upon completion of the installation, these instructions should be handed to the user of the appliance for future reference.

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What to do if you smell gas

• Close gas valve. Open windows.

• Do not try to light any appliance.

• Do not touch any electrical switch; do not use any phone in your building.

• If you cannot reach your gas supplier, call the fire department.

• Immediately call your gas supplier from a neighbor’s phone. Follow the gas supplier’s instructions

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

Index

1Warning 3

2 Appliance details 4

2.1 Features 4

2.2 GWH 2400 ES Specifications (Technical data) 4

2.3 Unpacking the GWH 2400 ES heater 5

2.4 General rules to follow for safe operation 6

2.5 Dimensions and Minimum installation clearances 7

3 Installation instructions 8

3.1 Tools required for installation 8

3.2 Introduction 8

3.3 Venting 8

3.4 Combustion air requirements 15

3.5 Proper location for installing your heater 16

3.6 Heater placement and clearances 16

3.7 Mounting installation 16

3.8 Gas piping & connections 17

3.9 Water connections 20

3.10 Water quality 20

3.11 Recirculation application 21

3.12 Measuring gas pressure 21

6 Maintenance and service 27

6.1 Annual maintenance 27

6.2 Winterizing for seasonal use 27

6.3 Mineral scale build-up 28

6.4 Adjusting CO2 (carbon dioxide) 28

6.5 Program values 31

6.6 Control board diagnostics 32

6.7 Fan speed adjustment 33

7 Troubleshooting 35

7.1 Introduction 35

7.2 Burner do not ignite when hot water is turned ON 35

7.3 Water is too hot 35

7.4 Water is not hot enough 35

7.5 Low water flow/pressure 36

7.6 Hot water temperature fluctuates at tap 36

7.7 Noisy burner/heater during operation 36

8 Problem solving 38

8.1 Error code diagnostics 38

9 Electrical diagram 42

4 Electrical connections 23

4.1 Electrical power supply 23

4.2 Position of the fuses in control unit 23

5 Operation instructions 24

5.1 LCD Display functions 24

5.2 For your safety read before operating your water heater 25

5.3 Power 25

5.4 Temperature selection 25

5.5 Use of optional remote control accessory (part no. TSTAT2) 26

5.6 Operation 26

5.7 Reset button 26

5.8 Program button 26

5.9 Locked condition 26

10 Sensor resistance charts 43

11 GWH 2400 ES Functional scheme 45

12 Interior components diagram

and parts list 46

12.1 Interior components 46

12.2 Components diagram 48

13 Protecting the environment 54

14 Limited Warranty 55

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Warning

1 Warning

For your safety

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

Warning: Carefully plan where you install the heater. Correct combustion air supply and flue pipe installation are very important. If a gas appliance is not installed correctly, fatal accidents can result, such as carbon monoxide poisoning or fire.

Warning: Exhaust gas must be vented to outside using stainless steel vent material suitable for category III vent systems and temperatures up to 480°F. Vent piping must be sealed gas-tight to prevent possibility of flue gas spillage, carbon monoxide emissions and risk of fire, resulting in severe personal injury or death. Approved vent terminators must be used when penetrating to the outside.

FCC: This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.

Warning: Place the heater in a location where water leaks will do NO DAMAGE to adjacent areas or lower floors.

Warning: Field wiring connections and electrical grounding must comply with local codes, or in the absence of local codes, with the latest edition of the National Electric Code, ANSI/NFPA 70, or in Canada, all electrical wiring must comply with the local codes and the Canadian Electrical Code, CSA C22.1 Part 1.

Warning: Shock hazard: line voltage is present. Before servicing the water heater, unplug power supply cord from outlet. Failure to do so could result in severe personal injury or death.

Warning: The heater must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures equal to or more than 0.5 psig.

Fig. 1

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Appliance details

2 Appliance details

2.1 Features

Parts

• Key Pad interface control

• High power pre-mix compact burner with low NOx

emissions

• Modulating Gas Valve with constant gas:air ratio

control

• Modulating water valve for improved comfort and

temperature control.

High quality materials for long working life

• Copper heat exchanger

• High efficiency Ceramat Burner

• Compact space saver: mounts on a wall with a

supplied bracket.

Features

• Real-time diagnostics for troubleshooting/

informational purposes

• LCD Display with backlight

• On/Off and Temperature control switches

• Reset button

• Program button (Selectable temperature default)

• Failure codes for easy diagnostics and repair

• Easily removable one-piece cover

• Built in freeze prevention.

Note: Freeze prevention is not intended to protect plumbing outside the appliance or to keep the appliance from freezing for long periods.

Accessories (Bosch part #)

• Optional wireless remote control accessory to

operate with the appliance (TSTAT2)

• Outdoor kit (AQOK).

BOSCH is constantly improving its products, therefore specifications are

subject to change without prior notice.

Maximum input

175,000 Btu/h (51.2 kW)

Efficiency in %

Thermal efficiency > 82%

Min. Input

19,900 Btu/h (5.8 kW)

Temperature Control

Selection range: 100°F (38°C) - 140°F (60°C) Default temperature: 122°F (50°C) Stability: +/- 2°F (+/- 1°C)

Gas Requirement

Gas connection (inches) - ¾”

Inlet gas pressure under operation (with a high hot water flow rate)*

• Propane: 8” - 13” water column

• Natural Gas: 3.5” - 10.5” water column. * To measure gas pressure, see Measuring Gas

Pressure, chapter 3.12.

Water

• Hot water connection (inches) - ¾”

• Cold water connection (inches) - ¾”

• Water valve material: Polymer (PPS) (Polypropylene Sulfid)

• Minimum water flow: 0.65 gallon/minute (2,5 l/m). Note: Activation varies with inlet water temperatures from 0.65 - 1.6 gallon/minute.

• Minimum recommended water pressure: 30 PSI (2.07 bar)

• Minimum recommended well pressure: 40 PSI (2.75 bar), see chapter 3.9.

• Connections: – Bottom of heater

Combustion

•NOx ≤ 55 ppm

•CO ≤ 250 ppm (measured)

•CO

level set from factory, see chapter 6.4.

2.2 GWH 2400 ES Specifications (Technical data)

Approved in US/Canada

Capacity

Maximum flow rate: 6.4 GPM (24 l/min) at a 45°F (25°C) rise.

Maximum output

147,000 Btu/h (43.0 kW)

Dimensions

• Depth (in): 11¼” (286 mm)

• Width (in): 17

• Height (in): 30½” (775 mm)

• Weight: 67 pounds (30,5 kg).

Gas types

Natural Gas. LP Gas. Converting the gas type can only be done by a certified gas technician with a calibrated CO

” (452 mm)

analyzer.

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Appliance details

Call Bosch Water Heating through Bosch thermotechnology corporation for conversion instructions.

Voltage

120 V AC (60 Hz) nominal

Amperage

Idle - 40 mA Operation - ≤ 2.5 A

Noise

45 - 65 db (A)

Safety devices

• Flame failure device (ionization flame rod sensor)

• Pressure relief valve (supplied with heater)

• Over heat prevention (temperature limiter)

• Inlet temperature sensor

• Outlet temperature sensor

• Backflow temperature sensor.

Water protection

IP X4 (protection against water drops)

If appliance is installed at elevations between 2000ft and 4500ft, a

combustion gas analyzer is required for proper calibration of appliance. (see page

22).

2.3 Unpacking the GWH 2400 ES heater

Before installing the unit, be certain you have the correct heater for your type of Gas: Propane or Natural Gas. Identification labels are found on the

shipping box, and on the rating plate which is located on the right side panel of the cover.

Fig. 2 Rating plate

A Serial number B Type of gas

The box includes:

• GWH 2400 ES

• Pressure relief valve (150 psi / 200,000 Btu rating)

• Bracket for wall hanging the heater

• Exhaust vent adaptor (with 4 screws and gasket

provided)

• Combustion air inlet adaptor (with 3 screws and gas-

ket provided)

• Installation manual (manual can be downloaded at

www.boschhotwater.com)

• Product registration card

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• Energy Guide label.

Please complete and return the enclosed product registration card.

The GWH 2400 ES is not approved or designed for:

• Manufactured (mobile) homes, boats or any mobile

installation (modular homes are acceptable for installation)

• Use above 4500ft A.S.L. altitude

• Outdoor installation without installation of Outdoor

kit (AQOK)

• Space heating purposes

• Preheated inlet water supply.

Appliance details

To remove front cover

B Loosen the two Philips head screws located on

bottom rear of cover (see Fig. 3).

Fig. 3 Loosen the two screws

B Lift front cover panel upward and remove.

Fig. 4 Removing the front cover

To remove combustion cover (service only)

B Open the four clips and remove the combustion

cover see Fig. 5.

2.4 General rules to follow for safe operation

B 1. You must follow these instructions when you install

your heater. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/ NFPA 54. In Canada: The Installation must conform with CGA B149.(1,2) INSTALLATION CODES and /or local installation codes.

B 2. Carefully plan where you install the heater. Correct

combustion air supply and vent pipe installation are very important. If not installed correctly, fatal accidents can occur, such as carbon monoxide poisoning or fire.

B 3. When the unit is installed indoors and ROOM

SEALED (twin pipe) it is permitted to be located in bathrooms, bedrooms and occupied rooms that are normally kept closed. See chapter unit will be installed indoors and use indoor combustion air, the place where you install the heater must have enough ventilation. The National Fuel

Gas Code does not allow UNSEALED gas fired water heater installations in bathrooms, bedrooms or any occupied rooms normally kept closed. See chapter

(page 15).

B 4. You must vent your heater. See

VENTING.

B 5. The appliance and its gas connection must be leak

tested before placing the appliance in operation. The appliance must be isolated from the gas supply piping system by closing its individual manual gas shutoff valve (not supplied with heater) during any pressure testing at pressures in excess of ½ Psig (3.5 kPa).

B 6. Keep water heater area clear and free from

combustibles and flammable liquids. Do not locate the heater over any material which might burn.

B 7. Correct gas pressure is critical for the proper

operation of this heater. Gas piping must be sized to provide the required pressure at the maximum output of the heater, while all the other gas appliances are in operation. Check with your local gas supplier, and see the section on connecting the gas supply. See Section 3.8, page 17.

B 8. Should overheating occur or the gas supply fail to

shut off, turn off the gas supply at the manual gas shut off valve, on the gas line. Note: manual gas shutoff valve is not supplied with the heater but must be field installed.

B 9. Do not use this appliance if any part has been

underwater. Immediately call a qualified service technician to inspect the appliance and to replace any part of the control system and any gas control which has been underwater.

3.3 (page 8). If the

3.5 (page 16) and 3.4

chapter 3.3 on

Fig. 5 Remove the combustion cover

B 10. Failure to install heater correctly may lead to

unsafe operation and void the warranty.

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2.5 Dimensions and Minimum installation clearances

Appliance details

Fig. 6 Dimensions

1 On/Off button 2 Reset button 3 Program key 4 Power ON or stand-by LED 5 LCD display 6 Up button 7 Down button

Fig. 7 Minimum clearances

Note: For servicing access, a 2ft clearance to front cover is recommended.

Model GWH 2400 ES

TOP (A) 12”

FRONT (B) 1”

BACK 0”

SIDES 1”

FLOOR (C) 12”

Table 1 Minimum clearances

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Installation instructions

3 Installation instructions

3.1 Tools required for installation

• Philips head screwdriver

• Flat head screwdriver

• Adjustable wrench

• Level

• Thermometer

• Standard plumbing tools

•Manometer

• Drill

• Pipe wrench

• Adjustable pliers

• Pipe fitting tools

• Hacksaw with metal blades

•Hole saw.

3.2 Introduction

Please follow these instructions. Failure to follow instructions may result in:

B Damage or injury. B Improper operation. B Loss of warranty.

If you are unable to perform the tasks required to install this heater properly, please contact a locally licensed plumber or gas technician. Common installation practice is to determine the venting/intake system layout and penetration and then work back to the heater.

3.3 Venting

Warning: Proper end terminal / rain

cap must be used. Failure to do so may result in damage to the appliance.

This damage is not covered under the manufacturer's warranty.

Caution: The vent system must be

installed by a qualified installer in accordance with these instructions. If improperly installed, a hazardous condition such as explosion or carbon monoxide poisoning could result. Bosch Water Heating will not be responsible for improperly installed appliances.

Warning: In areas where outside temperatures routinely come close to freezing, sealed combustion operation is required. Use a concentric termination or separate terminations for combustion and vent, which must be installed on the same wall or roof surface, however never facing the direction of prevailing winds. Failure to do so may result in heat exchanger freezing up and bursting. This failure is not covered under the manufacturer's warranty.

3.3.1 Vent material and specifications

Establish vent clearances that comply with the vent manufacturer's specifications. In all cases, follow local codes. See Table 2.

Warning: Do not reduce the vent (exhaust and combustion) pipe sizes and do not common vent with any other vented appliance or stove.

Warning: Failure to vent the exhaust gases to the outside with sealed stainless steel vent pipe (AL29-4C)

Exhaust Vent

Intake Vent

Diam. Min.

lenght

3 or 4

inches

3 or 4

inches

3 feet 26 feet with

1 90° elbow

Max.

length

1 90° elbow and terminal

26 feet with 1 90°elbow

and terminal

Material

Sealed single wall

stainless steel

(AL29-4C)

Sealed PVC or

any other rigid

pipe

may result in dangerous flue gases filling the structure in which it is installed.

Table 2 Venting Specifications

The appliance should be located as close to the point

Warning: Do not mix vent pipe or joining methods from different manufacturers.

of vent termination as possible. The maximum vent length is 26 feet (8 m) with one 90 degree elbow and approved terminator. Subtract 2.5 feet from the total vent length for each additional 90° elbow used (a maximum of three 90° elbows are permitted in the total exhaust vent length), or subtract 1.25 feet for every 45° elbow used. Horizontal sections of vent must pitch

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Installation instructions

upwards towards termination ¼" for every foot of horizontal length, to prevent the pooling of condensate, and be supported at 4 foot intervals with overhead hangers.

Exception: horizontal run between last elbow and termination must pitch down to termination 1/4" per foot. Note: For horizontal terminations, venting must

terminate once it penetrates to the outside of the structure. There must be no sections of vent pipe exposed to the outdoors. Note: Listed thimbles or collars are necessary where venting passes through wall and ceiling partitions. If the vent system passes through combustible areas where the vent clearance requirements cannot be maintained, it is permissible to chase straight sections of sealed 3 inch single wall vent through 4 inch (or greater) Type-B vent. The distance to combustibles using this chase technique is 1 inch

. Note: Type-B vent must never

be used as the actual exhaust vent system for the appliance, as it is not gas tight and illegal for use with this appliance. This will create a serious health hazard and void the warranty.

3”

VENTING

3”

Horizontal

Terminal

3” Vertical terminator

Z flex Protech Heat Fab

2SVSTB03 FSTB3 9390 TEE

2SVSRCF03 FSRC3 5300CI

Table 3 Terminator Part Numbers

Fittings or Piping Equivalent

feet m

45 degree elbow 1.25 0.38

90 degree elbow 2.5 0.76

pipe per foot 1 0.30

Table 4 Friction Loss Equivalent in piping and fittings

For specific questions concerning vent material, specifications, usage or installation, please contact the vent manufacturer directly.

Minimum exhaust vent length

Fig. 8

Maximum exhaust vent and combustion air inlet lengths

The maximum exhaust vent and combustion air inlet lengths with one elbow are ≥ 26ft.

Fig. 9 Maximum vent and combustion air lenghts

Note: reduce 2.5 ft for each 90° elbow used after the first one, reduce 1.25 ft for each 45° elbow, see table 2, page 8.

Refer to chapter 3.3.2, page 12 for condensate drain requirements.

Vent Safety System

The GWH 2400 ES will shut down if inadequate exhaust venting is detected or a lack of combustion air is provided to the unit; see troubleshooting section on page 35. See error code to confirm error, correct the problem and then reset the heater before operating.

Company Contact info

Z-flex www.z-flex.com

800-654-5600

ProTech Industries www.protechinfo.com

800-766-3473

Heat-Fab www.heatfab.com

800-772-0739

Table 5 Vent manufacturers

1) in all cases, follow local codes.

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Installation instructions

Recommended exhaust vent terminator position

Fig. 10

Ref. Description Minimum distance

C From any internal corner 12 in

F From a terminator facing a terminator 48 in

G Vertically between two exhaust vent terminators on the same wall 60 in

H Horizontally between two exhaust vent terminators on the same wall 36 in

I**

J From any external corner 12 in

Directly below an opening; operable windows, doors and any nonmechanical fresh air openings

Below a gutter, sanitary pipework or eaves 24 in

Below a gutter, sanitary pipework or eaves, protected by metal shielding

Above ground or snow pack 12 in

Above a paved sidewalk 7 ft

From an opposing wall or structure facing the termination 24 in

From the relief valve of a Ip gas regulator 60 in

Horizontally and vertically from combustion air inlet of a twin pipe system

From the gravity combustion air inlet any other equipment 6 ft

Horizontally from an opening; operable windows, doors and any nonmechanical fresh air openings

36 in (twin pipe installation)

48 in (single pipe installation)

12 in

36 in

12 in (twin pipe installation)

48 in (single pipe installation)

Vertically from a wall, roof slope, or obstruction (venting through a flat or pitched roof)

see ABOVE THE ROOF

requirements on following page

Table 6

* Subject to local codes and anticipated snow level ** Other equipment that operates with a mechanical air inlet may require greater distances, reference manufacturer's instructions NOTE: terminating exhaust vent under a deck is not permitted

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Venting configuration examples

Fig. 11 Horizontal side wall venting installation

(combustion air piping not shown)

Installation instructions

Fig. 13 Above the roof clearance requirements from

rain cap (combustion air piping not shown)

Important: Note: Pitch horizontal runs down toward the

heater, except horizontal run between last elbow and termination which must slope down to termination 1/4" per foot.

Note: For horizontal terminations, venting must terminate once it penetrates to the outside of the structure. There must be no sections of vent pipe exposed to the outdoors.

Fig. 12 Vertical venting installation (combustion air

piping not shown)

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Fig. 14 Vertical venting installation - Masonry

Chimney (combustion air piping not shown)

Installation instructions

3.3.2 Condensate drain requirements

A condensate drain must be installed under the following conditions:

• All vertical terminating vent installations

• Horizontal terminating vent installations where the total equivalent exhaust vent length is greater than 10 feet. See table 17, page 33.

• Vent installations where any section of the exhaust vent pipe passes through an unconditioned space.

Note: Do not install condensate drain in areas where it may freeze.

1. Install condensate drain as close to heater as

possible.

2. Use 3/8" ID high temperature silicone tube to

connect to condensate drain port. Do not use copper piping for any portion of the condensate drain.

3. Form a condensate trap by means of a 3" loop

partially filled with water.

4. To increase the tube length, connect to end of the

high temperature silicon tubing with vinyl tubing, PVC or CPVC pipe. Do not reduce the internal diameter at any point.

5. Dispose of condensate according to local codes.

Room sealed installation (TWIN PIPE SYSTEM)

Installing this water heater as a room sealed (TWIN PIPE SYSTEM) is the recommended method. Contact your dealer for available vent termination kits and vent materials for this water heater. The exhaust and combustion air piping must vent directly to the outside of the structure.

Fig. 15 Condensate drain installation

3" Venting Z-flex ProTech Heat Fab

90° Condensate Drain Tee

Horizontal Condensate Drain

Condensate Drain Tube

2SVEVWCF03 FST3 &

FSDF3

2SVEDWCF03 FSHDT3 9321

2SVEDTK24 N/A 7000TUBE

93PPLSTEE

Table 7 Approved Condensate Drain Part Numbers

Fig. 16

Combustion air pipe: ≤ 26 ft (8 m) from collar Exhaust vent pipe: ≤ 26 ft (8 m) from collar

Fig. 17

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Installation instructions

Warning: Approved terminators must

be used for inlet and exhaust vent systems to prevent rain from entering the appliance, failure to do so may result in damage to the appliance. This failure is not covered under the manufacturer’s warranty.

first one, reduce 1.25 ft for each 45° elbow. A maximum of three 90-degree elbows are permitted.

Determining installation adjustment

The GWH 2400 ES comes factory set to accomodate most common venting arrangements. Determine the elbows and straight pipe you will require for exhaust and combustion air. Refer to the the table below to determine if the factory setting for the fan is adequate. If your venting system is longer and exceeds the values listed in Table 8, proceed to Section 6.7, page 33 for fan speed adjustment.

TWIN PIPE

Exhaust

Intake

1 x 90° elbow or Less

2 x 90° elbow

One 90° elbow

or Less (feet)

Two 90°

elbows

19’ 16.5’ 14’

16.5’ 14’ 11.5’

Three 90°

elbows

Fig. 18

Open combustion installation (SINGLE PIPE SYSTEM)

Not recommended in cold climate areas, see chapter 3.4, page 15.

Fig. 19

Connecting a one piece 90 degree elbow pipe to the combustion air inlet adaptor is required. This will prevent debris or objects from falling into the appliance.

The exhaust vent system must vent directly to the outside of the building and an adequate amount of indoor combustion air must be provided for this installation. See chapter 3.4. Note: reduce 2.5 ft for each 90° elbow used after the

3 x 90° elbow

SINGLE PIPE

No intake piping

14’ 11.5’ 9’

19’ 16.5’ 14’

Maximum combined intake and exhaust vent length without

fan speed

adjustment.

Table 8

Note: Maximum of three 90° elbows allowed for exhaust and three 90° elbows allowed for intake.

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Installation instructions

3.3.3 Vent connections

B Attach the flue gas exhaust accessory (8 705 504

151) to the top of the unit (position 1) using the 4 screws and gasket provided. Fully insert stainless steel vent pipe 1.5” minimum into the accessory and tighten the clamp (position 2).

Fig. 20

B Attach the combustion air inlet accessory (8 705

504 154) to the top of the unit (position 3) using the 3 screws and gasket provided, and install air intake pipe over the accessory. NOTE: The appliance has the option to mount the combustion air inlet accessory on the top right or on the top left side of the heater. The combustion air inlet that is not used must be kept sealed.

Fig. 21

B Ensure that exhaust vent pipe is fully inserted in collar

to enable proper connection.

Exhaust venting must be 3" or 4" sealed single wall stainless steel (AL29-4C) vent

pipe.

Attention residents of the Commonwealth of Massachusetts:

In the Commonwealth of Massachusetts the following regulation went into effect on 12/30/2005:

(a) For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting, including but not limited to decks and porches, the following requirements shall be satisfied:

1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall horizontal vented gas fueled equipment, the installing plumber or gasfitter shall observe that a hard wired carbon monoxide detector with an alarm and battery back-up is installed on the floor level where the gas equipment is to be installed. In addition, the installing plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on each additional level of the dwelling, building or structure served by the side wall horizontal vented gas fueled equipment. It shall be the responsibility of the property owner to secure the services of qualified licensed professionals for the installation of hard wired carbon monoxide detectors.

a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an at tic, the hard wired carbon monoxide detector with alarm and battery back-up may be installed on the next adjacent floor level.

b. In the event that the requirements of this subdivision can not be met at the time of completion of installation, the owner shall have a period of thirty (30) days to comply with the above requirements; provided, however, that during said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall be installed.

2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in accordance with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.

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

4. INSPECTION. The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and

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Installation instructions

signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4.

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

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

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

(c) MANUFACTURERS REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM REQUIRED. When the manufacturer of Product Approved side wall horizontally mounted gas equipment provides a venting system design or venting system components with the equipment, the instructions provided by the manufacturer for the installation of the equipment and the venting shall include:

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

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

(d)MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED. When the manufacturer of a product approved side wall horizontally vented gas fueled equipment does not provide the parts for the venting of flue gases, but identifies "special venting systems," the following requirements shall be satisfied by the manufacturer:

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

2. The "special venting systems" shall be product approved by the Board, and the instructions for that system shall include a parts list and detailed installation instructions.

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

3.4 Combustion air requirements

Warning: In areas where outside

temperatures routinely come close to freezing, sealed combustion operation is required. Use a concentric termination or separate terminations for combustion and vent, which must be installed on the same wall or roof surface, however never facing the direction of prevailing winds. Failure to do so may result in heat exchanger freezing up and bursting. This failure is not covered under the manufacturer's warranty.

Warning: When installed in an environment where corrosive chemicals or dirty air are present the twin pipe system is required.

Twin pipe

The GWH 2400 ES is designed as a sealed combustion appliance. It is recommended that the combustion air be provided by a dedicated 3” or 4” pipe from the outside. The combustion air pipe may be PVC or any other rigid sealed 3” or 4" pipe. The combustion air piping must pitch down 1/4 inch per foot towards termination to prevent rain water from entering the appliance. The combustion air inlet, whether terminating vertically or horizontally, must be located in such a

manner as to provide a minimum 3 foot clearance from the exhaust vent terminator. See Fig. 10 Letter I, page 10. The maximum length of the combustion air inlet is 26 feet with one elbow. Subtract 2.5 feet for each additional 90° elbow and 1.25 feet for each additional 45° elbow. Maximum number of elbows permitted is 3.

Warning: Vent terminations must

prevent rain from entering the combustion air and exhaust vent piping.

Single pipe Note: This appliance requires 8750 cubic feet of

available combustion air, or a minimum of 1094 square feet of space with an 8 foot ceiling to operate. If the large amount of air space, which equates to about half of most average sized homes, is not available, the appliance must pull air from outside (see twin pipe system above).

Although it is permissible to draw combustion air from inside the structure, it is not the manufacturer’s recommended installation method. Always install a 3 inch elbow on the top of the combustion air inlet adaptor to prevent foreign objects from falling into the unit. If a single pipe installation is utilized, follow guidelines

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Installation instructions

below for providing adequate combustion air for the water heater as well as any other appliances that may consume air in the space. Always follow local codes if they are more stringent.

This Installation Manual specifies the minimum exhaust vent length (Fig. 8, page 9) and the amount of combustion air required for this unit. When all requirements are followed, the unit will operate properly and safely. However, there may still be a risk of freezing due to negative draft if the other combustion appliances in the building are not supplied with sufficient combustion air. A wood stove or furnace can pull its combustion air from the heater's vent pipe, allowing the cold incoming air to freeze the cold water in the heat exchanger. Supplying more combustion air for all combustion appliances is the solution. A HVAC specialist should be consulted to design solutions for providing more combustion air. Observe the following guidelines: Installations in structures that have been tightly constructed (air infiltration rate of 0.40 ACH or less) must be provided with combustion air per the National Fuel Gas Code. Consult a HVAC specialist if your air infiltration rate is questionable. The space must have two permanent openings, one commencing within 12 inches of the top and one commencing within 12 inches of the bottom of the enclosure.

Each opening must have a minimum free area of one square inch per:

• 1000 Btu/hr if all air is taken from inside the building

• 2000 Btu/hr if all air is taken from the outside by horizontal ducts

• 4000 Btu/hr if all air is taken from the outside by direct openings or vertical ducts.

B 1. Locate the heater where venting, gas and

plumbing connections are feasible and convenient.

B 2. The hot water lines should be kept short and

insulated to save energy. Centrally locating the water heater is recommended to keep hot water distribution times even throughout the structure.

Warning: The water in this water heater is cold and always remains cold except for the times the burner is on. In the event of power outage in conjunction with freezing temperatures, it is recommended that the heater be drained. See chapter 6.2, page 27 “Winterizing” for draining instructions.

Warning: Flammable materials, gasoline, pressurized containers, or any other items or articles that are potential fire hazards must NOT be placed on or adjacent to the heater. The appliance area must be kept free of all combustible materials, gasoline and other flammable vapors and liquids.

3.6 Heater placement and clearances

The GWH 2400 ES is approved for installation on a combustible wall (see chapter 3.7 Mounting installation) provided the floor covering below the heater is noncombustible. For installations in an

alcove or closet, maintain the minimum clearances to combustible and non-combustible materials listed below. See also Fig. 7 and Table 1 on page 7.

Or the space must be provided with one permanent opening or duct that is within 12 inches of the ceiling of the enclosure.

This opening must have a minimum free area of one square inch per:

• 3000 Btu/hr if all air is taken from the outside by a direct opening or vertical duct.

Louvers, grills and screens have a blocking effect. If the effective free area is not known, increase the sizes of your openings by 300% if your louvers are wood and by 43% if your louvers are metal. Refer to the National Fuel Gas Code for complete information.

3.5 Proper location for installing your

heater

Carefully select the location of the water heater. For your safety and for proper heater operation, you must provide combustion air to the heater and a proper exhaust vent system. Follow the guidelines below:

Clearances from any exhaust vent pipe are dependent upon the clearance requirements of the stainless steel vent pipe manufacturer. Single wall stainless steel (AL29-4C) vent pipe (vent type rated for Category III appliances) must be used when exhaust venting this appliance. See chapter 3.3 (page 8) Venting.

3.7 Mounting installation

Warning: before starting installation

B Check that there are no loose or

damaged parts inside the appliance

B Confirm the gas type of the heater

matches the gas supply you will be connecting the heater, see Fig. 2,

page 5.

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Front cover should be removed (see instructions on page 6) in order to inspect

components visually.

Warning: Do not install this appliance on a carpeted wall. The heater must be mounted on a wall using appropriate anchoring materials.

If wall is sheathed with plaster or drywall, it is recommended that two support boards, either 1”x4” or 1/2" (minimum) plywood first be attached across a pair of studs, see Fig. 22.

B Secure the wall mounting bracket provided with the

heater to the wall surface. The heater must be kept level on the wall surface (see Fig. 23).

B Hang the appliance on the bracket, see Fig. 24.

Installation instructions

Fig. 23 Leveling the mounting bracket on the studs

Studs 16"

(406mm) on

center

Fig. 22 Distance between support boards

Fig. 24 Mounting the heater

Warning: Appliance must be installed vertically.

3.8 Gas piping & connections

Before connecting the gas supply, check the rating plate on the right side of the heater to be sure that the heater is rated for the same gas to which it will be connected. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada: The Installation must conform to CSA B149

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