Bradford-White B4 User Manual

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Installation, Operation and Maintenance Instructions Document 2143

Installation, Operation and Maintenance Instructions for

Copper Brute

Volume Water Heaters

Model B4 Sizes 175-400

FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician, qualified in hot water heater installation and maintenance. Improper installation and/or operation could create carbon monoxide gas in flue gases which could cause serious injury, property damage, or death. Improper installation and/or operation will void the warranty.

WARNING

If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

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

WHAT TO DO IF YOU SMELL GAS

Do not try to light any appliance.

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

Immediately call your gas supplier from a nearby 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 gas supplier.

H2317000-

BRADFORDWHITE®

C O R P O R A T I O N

Internet Version for Reference Only

Page 2 BRADFORD WHITE

TABLE OF CONTENTS

SECTION 1.

General Information

3.5

Hi-LimitSwitch Checkout..............................

22

3.6

Shut-DownProcedure..................................

22

1.1

Introduction.....................................................

3

SECTION 4.

 

1.2

Warranty.........................................................

3

 

1.3

Technical Assistance ......................................

3

Maintenance

 

SECTION 2.

 

4.1

General Instructions .....................................

23

 

4.2

Replacement of Gas Controls ......................

23

Installation Instructions

 

4.3

Heat Exchanger............................................

25

2.1

General Information........................................

4

4.3.1

Inspecting the Heat Exchanger ....................

25

2.2

Field Assembly ...............................................

4

4.3.2

Cleaning the Heat Exchanger.......................

25

2.3

Site Location...................................................

5

SECTION 5.

 

2.3.1

Installation Information ...................................

5

 

2.3.2

Outdoor Installation (U.S. only) ......................

5

Troubleshooting

 

2.3.3

Flooring - Typical Installation..........................

6

5.1

Gas Pressure Tests

26

2.4

Combustion and Ventilation Air Supply

6

5.1.1

Checking the Main Line Gas Pressure

26

2.4.1

Outdoor Air Supply

7

5.1.2

Checking the Manifold

 

2.4.2

............................................Indoor Air Supply

7

 

Regulated Gas Pressure..............................

26

2.4.3

...................................Exhaust Fans or Vents

7

5.2

Electrical Troubleshooting

26

2.5

Venting of Combustion Products

8

5.2.1

Heater Does Not Come On

27

2.5.1

General Information

8

5.2.2

Testing the Transformer

27

2.5.2

Replacement of Existing Heater

8

5.2.3

Testing the Electrical Power Supply

28

2.6

Water Flow

8

5.2.4

Testing the Manual Reset

 

2.6.1

.......................Reversible Water Connections

8

 

Hi-LimitSwitch..............................................

28

2.6.2

...........................................Water Chemistry

11

5.2.5

Testing the Flow Switch

28

2.6.3

Freeze Protection

11

5.2.6

Testing the Fusible Link

 

2.6.4

............................................Water Hardness

11

 

(Flame roll-outswitch)..................................

28

2.6.5

.....................................Pump Requirements

11

5.2.7

Testing the Fuse

29

2.6.6

Pressure Buildup in Water System

14

5.2.8

Testing the Ignition Control

 

2.6.7

...................................Pressure Relief Valve

14

 

(for spark ignition).........................................

29

2.6.8

.............................................Water Pressure

14

5.2.9

Testing the High Voltage Ignition Lead

29

2.6.9

Pump Installation

14

5.2.10

Testing the Safety Shutoff

 

2.6.10

..............................Storage Tank Installation

15

 

(for standing pilot).........................................

30

2.6.11

Thermal Circulation of Hot Water in

 

5.2.11

Testing the Safety Shutoff

 

 

Cold Water Supply Lines

15

 

 

 

(for automatic pilot)

30

2.7

Gas Supply and Piping

15

 

5.2.12

Testing the Igniter Electrode

30

2.7.1

General Instructions

15

5.2.13

Testing the Pilot Thermocouple

 

2.7.2

..........Special Precautions for Propane Gas

16

 

(for standing pilot).........................................

30

2.8

............................................Electrical Wiring

16

5.2.14

Testing for Pilot burner

 

2.9

Combined Space Heating/Potable

 

 

(for spark ignition)

30

 

Water Heating Systems

16

 

 

5.2.15

Testing for Burner Ignition

 

2.9.1

Combined Space Heating

16

 

 

(for standing pilot).........................................

31

SECTION 3.

 

5.2.16

Heater Will Not Shut Off ...............................

31

 

5.2.17

On-OffMain Burner Cycling .........................

31

Operating Instructions

 

5.2.18

Testing the Terminal Strip/External

 

3.1

Normal Operating Sequence........................

16

 

Controls........................................................

31

3.2

Start-UpProcedure.......................................

21

 

 

 

3.3

Setting the Temperature Controls.................

21

 

 

 

3.3.1Remote Water Heater Temperature

Control:.........................................................

21

3.3.2Internal Water Heater Temperature

Control:.........................................................

22

3.4Adjustment for Minimum Input Rate

(models with modulating gas valve) .............

22

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Copper Brute B4 Volume Water Heaters Page 3

SECTION 1.

General Information

1.1Introduction

This manual provides installation, operating, and

maintenance instructions for Copper Brute Volume Water Heaters, Sizes 175 through 400. Review all application and installation procedures completely before proceeding with the installation. Experience has shown that most operating problems are caused by improper installation.

1.2Warranty

The Copper Brute heaters are sold with a limited

factory warranty.

Make all warranty claims to an authorized Bradford White representative or directly to the factory. Claims must include the heater serial number and model (this information can be found on the rating plate), installation date, and name of the installer. Shipping costs are not included in the warranty coverage.

Some accessory items are shipped in separate packages. Inspect everything for damage immediately upon delivery, and advise the transporter of any shortages or damage. Any such claims should be filed with the transporter. The transporter will not accept a claim from the shipper, Bradford White.

The warranty does not cover damage caused by improper installation, operation, or field modification.

1.3Technical Assistance

Consult Bradford White or your local wholesaler

with any questions or problems involving the specification, installation and operation of Bradford White equipment. An experienced technical support staff is ready to assist in assuring the proper performance and application of Bradford White products.

 

 

 

 

 

 

 

V

 

 

 

 

 

 

 

 

 

OPTIONAL

 

D

 

 

 

 

 

VENT CAP FOR

 

 

 

 

 

 

OUTDOOR USE

DRAFTH

 

TOP VIEW

 

 

 

C

 

 

 

 

 

 

 

 

 

 

BE INST

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

THE FIE

A

 

SIDE VIEW

 

 

 

 

 

B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

OUT

 

 

 

 

 

INLET

 

 

 

 

 

 

 

8-1/2in.

 

 

 

 

 

 

 

 

 

 

(216mm)

 

 

 

 

 

5-1/2in.

 

 

 

INLET OUTLET

 

30-3/16in.

(767mm)

 

 

 

 

(140mm)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dimensions shown in inches cm.

 

 

 

 

 

26-1/2in.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Gas Connection

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Size

 

Water

 

 

 

 

 

C

 

 

C

 

V

 

 

 

 

 

Connect.

 

 

 

 

 

U.S. Only

(Indoor)

Vent

 

 

 

 

 

 

 

 

 

 

 

 

Nat.

Propane

Size

 

 

A

 

 

B

(Outdoor)

 

 

 

Dia.

Size

in.

mm

in.

mm

in.

mm

 

in.

cm

in.

cm

in.

cm

in.

cm

in.

mm

175

3/4

19

1/2

13

11/2

38

 

18

46

261/2

67

141/16

36

23/2

60

6

152

 

250

3/4

19

1/2

13

11/2

38

 

221/2

57

31

79

181/16

47

243/4

63

7

178

 

325

3/4

19

1/2

13

11/2

38

 

263/4

68

353/4

91

193/16

49

257/8

66

8

203

 

400

3/4

19

1/2

13

11/2

38

 

313/4

80

401/4

102

225/8

58

267/8

68

9

229

 

Note:

Dimensions

may vary.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 1. General configuration.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Page 4

SECTION 2.

Installation Instructions

2.1 General Information

WARNING

Follow local regulations with respect to installation of carbon monoxide (CO) detectors and manufacturer's maintenance schedule of the heater.

Install the Copper Brute heaters in accordance with the procedures in this manual (or the warranty may be voided), local codes and ordinances. In the absence of such codes, install the heaters in accordance with the latest edition of the National Fuel Gas Code, ANSI Z223.1. In Canada, the installation must be

in accordance with CAN1-B149.1or .2 and local codes. The authority having jurisdiction may require the installation conform to the Standard for Controls and Safety Devices for Automatically Fired Heaters, ANSI/ASMECSD-1.Any changes to the heater, gas controls, gas orifices, wiring or draft diverter may void the warranty. If field conditions require a change to any of the above, consult the factory.

All gas-firedproducts require correct installation to assure safe operation. The requirements for heaters include the following:

1.Field assembly of drafthood or vent cap (see Section 2.2).

2.Appropriate site location (clearances) and flooring.

3.Sufficient combustion and ventilation air.

4.Adequate venting of combustion products.

5.Adequate water flow.

6.Properly sized gas meter and piping.

7.Proper electrical wiring.

This manual provides the information needed to meet these requirements. Review all application and installation procedures completely before continuing the installation.

2.2Field Assembly

The Copper Brute heater is shipped from the

factory with the top assembly in the low-profileconfiguration for outdoor installations.

The Copper Brute heater is design certified for indoor installation when equipped with a special drafthood, which must be installed without

modification. The part number for the drafthood is on the heater rating plate. Follow this procedure to make the conversion:

BRADFORD WHITE

a.Remove the top filler plate, stamped “HOT”, by slipping a fine-bladescrewdriver into the slot at the rear of the plate and gently prying it up (see Figure 2).

b.Remove the two screws attaching the adapter plate to the top assembly and lift it out (see Figure 3).

c.Remove the vent cap or drafthood from its package.

d.Disengage the flue transition ring from the stack extension and place it on top of the collector assembly as shown in Figure 4.

T

HO

Figure 2. Top filler plate.

Figure 3. Adapter plate.

Figure 4. Flue transition

Figure 5. Vent cap with

ring.

adapter plate

 

(outdoor).

Figure 6. Drafthood with

adapter plate

(indoor).

Figure 7. Drafthood switch receptacle.

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Copper Brute B4 Volume Water Heaters Page 5

e.Slide the adapter plate over the bottom of the stack extension as shown in Figure 5. Fit the stack extension down over the flue transition ring. Seat the adapter plate on the top assembly and secure it with two screws (see Figure 6).

f.Indoor models, size 175 and 250 only, require an adapter cable (included with product). The cable connects the blocked vent safety switch (BVSS) on the bell of the external draft hood to the 6-positionMolex plug on the side of the unit (see Figure 7). Refer to instruction sheet included with cable.

2.3Site Location

2.3.1 Installation Information

WARNING

Improper installation or maintenance can cause nausea or asphyxiation from carbon monoxide in flue gases which could result in severe injury, property damage, or death.

Avoid placing the heater in locations where it can be damaged by water or condensate leakage. If this is not possible, provide a suitable drain pan to catch and divert any leakage. The pan must not block natural flow of air around the heater.

Locate the heater to provide adequate clearance on all sides for inspection, service and to provide adequate air circulation for proper operation.

Locate the heater so the clearances from combustible surfaces shown in Table 1 and Figure 8 are met.

Locate the heater on a waterproof floor with a floor drain and a 6 inch (152 mm) minimum curb on all four sides to protect the building if heater repairs are needed.

Clearance from:

Indoors

Outdoors

inch

mm

inch

mm

 

 

 

 

Top

37

940

Unobstructed

Water conn. side

12

305

Unobstructed

Opposite side

6

152

6

152

Front

Alcove

Unobstructed

Rear

6

152

6

152

Vent*

6

152

 

Flooring

Combustible

Combustible

Service clearance = 36 inches (914mm) at front of heater, and 18 inches (457mm) at water connection side.

*1" (25mm) if double wall vent is used.

Table 1. Minimum Boiler Clearances from Combustible Surfaces.

Closet Installation

Room Installation

(unacceptable)

(acceptable)

A closet is any 4 sided enclosure which is less than 16* times the total volume of all the gas fired appliances within the enclosure.

A room is any enclosure which is at least 16* times greater than the total volume of all the gas fired appliances within the enclosure

Alcove Installation

(acceptable)

An alcove suitable for the installation of a heater is a restricted section of a room not separated from the room by a door or partition and which meets the minimum clearances specified in this manual.

* When the ceiling height exceeds 8 feet, you are only allowed to consider 8 feet when calculating the total volume of the enclosure.

Figure 8. Alcove installation.

2.3.2 Outdoor Installation

Caution

Outdoor installations are not recommended in areas where the danger of snow blockage exists. Copper Brute heaters can be installed in the standard lowprofile, grate top configuration as received from the factory, or with an optional vent cap.

Locate the heater in an open, unroofed area. Do not locate the heater below or adjacent to any doors, windows, louvers, grills, etc., which connect in any way with an inhabited area of a building, even though the access might be through another structure such as a garage or utility room (see Figure 9 and Table 1). There must be a minimum of 4 feet (1.22 m) horizontally and vertically between the heater and any door, window, or gravity inlet to a building (see Figure 10).

If the heater is installed close to a structure, protect it from rain water runoff with rain gutters on the roof or other measures. Do not locate the heater near sprinkler systems that could spray water on it.

Avoid locations where wind deflection off nearby structures might cause wind loading and downdraft conditions. Where downdraft conditions exist, locate the heater at least 3 feet (0.91 m) from the structure.

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Page 6 BRADFORD WHITE

WINDOW

 

OR GRILL

 

ONG

WR

INDOOR

ROOM

 

Figure 9. Incorrect outdoor installation.

 

4

ft

 

(1.2m)

4 ft

4

ft

(1.2m)

(1.2m)

Figure 10. Outdoor location installation.

2.3.3 Flooring - Typical Installation

Do not install the heater directly on carpeting without placing anon-combustibleplatform between the carpeting and the heater. If the heater is installed in a carpeted alcove, the entire floor of the alcove must be covered by anon-combustiblepanel. The panel must be strong enough to carry the total weight of the heater and all piping, pumps, and any other equipment attached to the heater. For rooftop installation, see Figure 11 through Figure 13.

2.4 Combustion and Ventilation

Air Supply

All indoor installations must have openings to outside air for combustion, ventilation and dilution of flue gases from inside the building (see Figure 14 and Table 2 ). Bradford White does not recommend indoor installations that do not provide combustion air from outside the building.

Concrete slab must extend out a minimum of 12 in. (305mm) on all sides.

Bradford White

UNIT

(Side View)

Base For Combustible Floors

Roof - Wood and Steel Construction

Figure 11. Standard base for combustible floor.

20 Gauge

Galvanized

Sheet Metal

Cap

Roofing

Mounting Platform must extend out a minimum of 12 in. (305mm) on all sides.

Bradford White

UNIT

(Side View)

Base For Combustible Floors

Base Rail

Flashing

Raised Mounting

Roof

 

Platform (Wood)

 

Figure 12. Typical roof mounting.

 

Bradford White

Base Rail

 

20 Gauge

 

UNIT

 

Galvanized

 

(Side View)

 

Sheet Metal

 

 

 

 

Cap

Base For Combustible Floors

Roofing

 

Flashing

4x4 Stringer

Roof

Figure 13. Typical roof mounting with standard combustible mount base.

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Copper Brute B4 Volume Water Heaters Page 7

 

Required Net Free Opening Area

 

 

Directly from Outside

 

 

 

 

 

 

 

At Top

At Bottom

Mode

in.2

cm2

in.2

cm2

175

44

284

44

284

250

63

406

63

406

325

82

529

82

529

400

100

645

100

645

Note: For screens or louvers, add 50%.

Table 2. Air Openings to Outside.

Vent terminated at

 

10 ft.

 

 

least 24 in.

 

 

Listed Vent

 

 

(3.0m)

(610mm) above

 

 

 

 

 

 

 

 

Cap

any object within

 

 

 

 

 

 

 

 

 

10 ft. (3.0m)

 

 

2 ft. (0.6m)

Storm Collar

 

 

 

 

 

 

 

 

 

 

1/14 in. (6mm)

 

Roof Jack

 

 

 

 

Minimum Pitch

 

 

 

Per Foot of

 

 

 

Horizontal Pipe

 

 

 

 

Drafthood

 

Adequate

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Air Supply

 

 

 

 

 

 

 

 

 

 

To Room

 

 

 

 

 

 

 

 

12 in.

 

Top and

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Botom

 

 

 

 

 

 

 

(305mm)

 

All Sides

Notes:

1. The drafthood must sit directly on top of the heater as shown and must not be altered in any manner.

2. An Underwriters' Laboratories listed vent cap is required to eliminate downdraft and allow the heater to function properly.

3. Use approved roof fitting.

Figure 14. Indoor installation and venting.

In the United States, the most common requirements specify that the space shall communicate with the outdoors in accordance with method 1 or 2, which follow. Where ducts are used, they shall be of the same cross-sectionalarea as the free area of the openings to which they connect.

Method 1:

Two permanent openings, one commencing within 12" (30 cm) of the top and one commencing within 12" (30 cm) of the bottom of the enclosure shall be provided. The openings shall communicate

directly, or by ducts, with the outdoors or spaces that freely communicate with the outdoors. When directly communicating with the outdoors directly, or through vertical ducts, each opening shall have a minimum free area of 1 square inch per 4000 Btu/hr (550 square mm/kW) of total input rating of all equipment in the enclosure. When communicating to the outdoors through horizontal ducts, each opening shall have a minimum free area of not less than 1 square inch per 2000 Btu/hr (1100 square mm/kW) of total input rating of all equipment in the enclosure.

Method 2:

One permanent opening, commencing within 12" (30 cm) of the top of the enclosure shall be permitted. The opening shall directly communicate with the outdoors or shall communicate through a vertical or horizontal duct to the outdoors or spaces that directly communicate with the outdoors, and shall have a minimum free area of 1 square inch per 3000 Btu/hr (734 square mm/kW) of the total input rating of all equipment located in the enclosure. This opening must not be less than the sum of the areas of all vent connectors in the confined space.

Other methods of introducing combustion and ventilation air are acceptable, providing they conform to the requirements in ANSI Z223.1, or applicable codes.

In Canada, Table 2 does not apply. Consult local building and safety codes or, in absence of such requirements, follow CAN/CGA B149.

NOTE: Check with louver manufacturers for net free area of louvers. If screens or louvers are installed, add 50 percent for each screen/louver to the net free area Check all local codes applicable to combustion air.

2.4.1 Outdoor Air Supply

When combustion air comes directly through an outside wall, each opening must have a minimum free area of at least one square inch for each 4,000 BTU/h input of the total input rating of all appliances in the enclosed area. (In Canada, refer to CGAB149.1 and .2.)

2.4.2 Indoor Air Supply

Confined and non-confinedareas have different requirements for installation. Consult the latest edition of the National Gas Code for installation requirements.

2.4.3 Exhaust Fans or Vents

Any equipment which uses air or removes air from the heater room can use up the combustion air supply or reverse the natural draft action of the venting system. This could cause flue products to build up in the heater room. More air must be supplied to make up for the decrease.

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Page 8 BRADFORD WHITE

2.5 Venting of Combustion Products

2.5.1 General Information

When installed indoors, the drafthood must be connected to a venting system. The venting system must be installed by a qualified installer and in accordance with the latest edition of ANSI Z223.1. In Canada, the installation must be in accordance with CAN1-B149.1or .2, and any local codes that apply.

The vent pipe must have a listed vent cap, and extend at least 2 feet (0.6 m) above any object within a 10 foot (3.0 m) radius.

NOTE: Do not use sheet metal screws at the snap lock joints of Type Bdouble-wallgas vents.

Do not weld or bolt the vent pipe to the heater drafthood. The weight of the stack must not rest on the heater. The drafthood and heater top must be easily removable for normal heater service and inspection.

WARNING

Avoid ending heater vents near air conditioning or air supply fans. The fans can pick up exhaust flue products from the heater and return them inside the building, creating a possible health hazard.

Avoid horizontal runs of the vent pipe and 90 degree elbows, reductions, and restrictions. Horizontal runs should have at least a 1/4 inch (6.3 mm) rise per foot in the direction of flow. Support a vent connector for the design and weight of the material used to maintain clearances and physical damage and separate of joints.

Always use double-wallor insulated vent pipe (Type B or equivalent).

WARNING

In cold weather, uninsulated outside vents can chill the rising flue products, blocking the natural draft action of the venting system. This can create a health hazard by spilling flue products into the heater room.

Avoid oversize vent piping or extremely long runs of the pipe which may cause too much cooling and condensation of flue gasses.

When the installation of a power vent or draft fan in the venting system is necessary, qualified personnel should design the installation following good engineering practices and all applicable codes. A suitable draft switch must be wired into the heater control circuit at the terminal designated Field Interlock to keep the heater from firing unless there is a positive draft.

2.5.2 Replacement of Existing Heater

When a heater is removed from a common venting system, the venting system may be too large for proper venting of the other appliances connected to it.

If replacing an existing heater with a Copper Brute heater and the existing heater was connected to a common venting system, the common venting system must comply with ANSI Z223.1/National Fire Protection Association (NFPA) 54. When resizing any portion of the common venting system, the common venting system should be resized to approach the minimum size as determined using the tables in ANSI Z223.1/NFPA 54, Appendix G. In Canada, the common venting system should be resized so the installation will be in accordance with CAN/CGA B149.1 or .2.

2.6 Water Flow

2.6.1 Reversible Water Connections

Bradford White ships the heater with the water connections on the right side. The heater can be installed with the water connections on either side. It could be necessary, or helpful, to switch the connections to the left side to improve access for installation service. Have a professional service technician perform this modification before installing the heater using the following procedures:

1.Remove the front cover.

2.If there is a vent cap or drafthood installed, they must be removed before removing the grate top assembly. On indoor installations (sizes 175250), the drafthood switch must be disconnected at the left side of the heater.

3.If the unit is in the low-profileoutdoor configuration, remove thehex-headscrews (see Figure 15) and lift the grate top assembly straight up.

4.Remove the screws that fastens the flue collector holddown clamps and remove the clamps (see Figure 16).

5.Remove the flue collector assembly by lifting it out of the chassis.

6.Remove the screws that fastens the gap closures and put them aside.

7.Remove the three grommets.

8.Remove the drain valves and plug. There is one hex plug on the left side, near the rear of the jacket. The drain valves are located on the left side and right side of the heater (see Figure 15).

9.Remove the four screws that fastens the metal channels covering the capillary tube on the right side of the jacket, and lay the channels aside.

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Copper Brute B4 Volume Water Heaters Page 9

HEAT EXCHANGER

 

REAR TILE COVER

ASSEMBLY

 

 

 

GAP CLOSURE

FLOW SWITCH

CONDUIT

DRAIN

DRAIN VALV

REAR TILE

COVER

GAP CLOSURE

GROMMET

DRAIN

VALVE

HEX HEAD

SCREWS

CHANNEL

MANUAL RESET CAPILLARY TUBE)

HIGH LIMIT

SWITCH BOX

STRIP

Figure 15. Heat exchanger reversal.

Clamp

Flue Collector

Bracket

Clamp

 

In/Out Header

Heat Exchanger

Bracket

Figure 16. Flue collector Holddown Clamps.

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Page 10 BRADFORD WHITE

10.In the control compartment, find the manual reset high-limitswitch box (see Figure 15) and loosen the screw on the top to remove the cover.

11.Loosen the screw that fastens the white wire and remove it from the terminal. Pull it out through the top of the case and separate the other white wire from the red wire coming from the fuse

2-Stage/

Operating Inlet Oulet High Limit Controller

Header

Modulating (if installed)

Figure 17. Sensory bulb locations.

Retaining

Clip

Figure 18. Retaining clip removal.

3.1 in. (79mm)

 

2.4 in.

0.9 in. dia

 

(61mm)

Attach Capillary

 

(23mm)

 

(Two holes)

Covers on

 

 

 

Left Side

2.4 in.

FRONT

 

(61mm)

1.9 in.

LEFT

(48mm)

 

Figure 19. Hole location, left side.

holder. Gently pull the two white wires out of the control compartment and coil them on top of the heat exchanger.

12. A temperature control sensing bulb is located in the front of the header on the inlet side and a manual reset hi-limitsensing bulb is located on the back side of the header on the outlet side (see Figure 17). Remove these sensing bulbs from the

header. The following steps for removal apply to all sensing bulbs:

a.If there is more than one capillary tube coming out of the header, label the capillary tubes.

b.Loosen the screw on the capillary tube retaining clip, then gently pry the clip apart until it comes free from the temperature control (see Figure 18).

c.Pull the sensing bulbs out of the temperature control.

d.Gently pull the capillary tubes into the control compartment.

e.Pull the temperature sensing bulb out of the header, and temporarily route it to the front of the heater.

13.Use a pair of diagonal cutters to cut the plastic tie around the wire bundle in the control compartment.

14.On the terminal strip, disconnect the two brown wires from No. 5 and No. 6 terminals.

15.Remove the flow switch conduit retaining clip and the elbow leading into the jacket.

16.Reach inside the control compartment and release the retaining nut in the upper right corner. The nut should only be finger-tight.

17.When the conduit is pulled away from the jacket, pull the two brown wires out of the control compartment. Coil the conduit and wires on top of the heat exchanger.

18.Use a chassis punch to put two 7/8 inch (22 mm) holes in the front left side of the jacket (see Figure 19).

19.Remove the front and rear tile covers (see Figure 15).

20.Lift out the heat exchanger assembly, turn it 180 degrees, and reseat the unit in the heater with the water connections on the left side.

21.Reinstall the front and rear tile covers.

22.Push the capillary tube(s) out through the lower hole in the left side of the jacket.

23.Install the sensing bulb(s) into the appropriate temperature control (keep in mind that the positions of the inlet and outlet have been reversed. The inlet is now behind the outlet).