Bosch AQ 125BO LP User Manual Download Page 11

8 716 473 147

Installation instructions

11

FOR NATURAL GAS

Maximum Capacity of pipe in Cubic Feet of Gas per Hour for Gas Pressure of 0.5 Psig or less and a Pressure drop
of 0.3 in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands.

Fig. 8

Follow boxed numbers for piping just one AQ125 BO (example: ¾” B.I. Natural Gas pipe for 20 ft (6.1m).
will handle 190,000 btu’s (55.7 kWh). For multiple appliances combine the total btu input load and then refer
to applicable chart below.

* EHD = Equivalent Hydraulic Diameter.  The greater the
value of EHD, the greater the gas capacity of the tubing

Maximum  Capacity  of  Semi-Rigid  copper  Tubing  in
Thousands  of  BTU  per  Hour  of  Undiluted  Liquefied
Petroleum  Gases  (at  11  inches  Water  Column  Inlet
Pressure).

(Based on a Pressure Drop of 0.5 Inch Water Column)

*  Source  National  Fuel  Gas  Code  NFPA  54,  ANSI
Z223.1  -  No  Additional  Allowance  is  necessary  for  an
ordinary number of fittings

FOR LP GAS

Maximum Capacity of Pipe in Thousands of BTU per Hour of Undiluted Petroleum Gases (at 11 inches Water Column Inlet
Pressure) (Based on a Pressure Drop of 0.5 Inch Water Column).

* EHD = Equivalent Hydraulic Diameter.  The greater the
value of EHD, the greater the gas capacity of the tubing. 

Nominal
Iron

Length of Black Iron Pipe, Feet

Pipe

Internal

Size

Diameter

inches

inches

10

20

30

40

50

60

70

80

90

100

125

150

175

200

1/4

0.364

32

22

18

15

14

12

11

11

10

9

8

8

7

6

3/8

0.493

72

49

40

34

30

27

25

23

22

21

18

17

15

14

1/2

0.622

132

92

73

63

56

50

46

43

40

38

34

31

28

26

3/4

0.824

278

190

152

130

115

105

96

90

84

79

72

64

59

55

1

1.049

520

350

285

245

215

195

180

170

160

150

130

120

110

100

1 1/4

1.380

1050

730

590

500

440

400

370

350

320

305

275

250

225

210

1 1/2

1.610

1600

1100

890

760

670

610

560

530

490

460

410

380

350

320

2

2.067

3050

2100

1650 1450 1270 1150 1050

990

930

870

780

710

650

610

Tube
size,
inches

EHD*

10

20

30

40

50

60

1/2

18 EHD 82

58

47

41

37

34

3/4

23 EHD 161 116

96

83

75

68

1

30 EHD 330 231

188

162

144

131

1 1/4 37 EHD 639 456

374

325

292

267

Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet 

Nominal
Iron pipe

Black Iron Pipe

size

Length of pipe, Feet

inches

10

20

30

40

50

60

70

80

90

100

125

150

1/2

275 189 152 129 114 103 96

89

83

78

69

63

3/4

567 693 315 267 237 217 196 185 173 162

146

132

1

107 732 590 504 448 409 378 346 322 307

275

252

1 1/4 220 149 121 103 913 834 771 724 677 630

567

511

1 1/2 330 229 185 155 141 127 118 108 102 976

866

787

2

622 433 346 299 264 239 220 204 192 1811 1606 1496

Tube
size
inches

EHD*

10

20

30

40

50

60

1/2

18 EHD 129 91

74

64

58

53

3/4

23 EHD 254 183

151

131

118 107

1

30 EHD 521 365

297

256

227 207

1 1/4 37 EHD 971 661

528

449

397 359

Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet 

Copper

Outside

Length of Tubing, Feet

diameter
Inch

10

20

30

40

50

60

70

80

90 100

3/8

39

26

21

19

_

_

_

_

_

_

1/2

92

62

50

41

37

35

31

29

27

26

5/8

199 131 107 90

79

72

67

62

59

55

3/4

329 216 181 145 131 121 112 104 95

90

Summary of Contents for AQ 125BO LP

Page 1: ...ury 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 What to do if you smell ...

Page 2: ...6 5 Hot water temp fluctuates from hot to cold 17 6 6 Water is too hot 18 6 7 Water is not hot enough 18 7 Interior components and diagram parts list 19 7 1 Interior components 19 7 2 Components diagram 20 7 3 Parts list 21 8 Protecting the environment 22 9 Twelve Year Limited Warranty 23 1 Warning Featuring Piezo Ignition For your safety Do not store or use gasoline or other flammable combustible...

Page 3: ...ot reach your gas supplier call the fire department Installation and service must be performed by a qualified installer service agency or the gas supplier Fig 1 Fig 2 Warning The heater must be isolated from the gas supply piping system during any pressure testing of that system at test pressures equal to or more than 0 5 psig Caution Any changes or modifications not expressly approved by the part...

Page 4: ...imum input 117 000 Btu h 34 3 kW Efficiency in Recovery efficiency 80 Min Output 28 000 Btu h 8 2 kW Gas Requirement Gas connection inches Inlet gas pressure under maximum operation Propane 10 5 14 water column Natural Gas 5 7 14 water column To measure Gas Pressure see Measuring Gas Pressure chapter 3 6 Water Hot water connection inches Cold water connection inches Water valve material Polymer PP...

Page 5: ...structions 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 should conform with CGA B149 1 2 INSTALLATION CODES and or local installation codes B 2 Carefully plan where you install the heater Proper clearances must be followed B 3 The appliance ...

Page 6: ...73 147 6 Appliance details 2 5 Dimensions and installation clearances Fig 3 Dimensions Fig 4 Minimum clearances Model AQ125 BO TOP A 3 ft FRONT B 4 ft BACK 0 SIDES 4 ft BOTTOM C 1 ft Table 1 Minimum clearances ...

Page 7: ... ever anticipated Danger If the temperature drops below 32 F freeze damage to the water heater itself must be prevented by turning off the power to the heater then disconnecting the plumbing conne ctions as well as removing the drain plug and introducing short bursts of compressed air 20 40 psi through the heater s connections This will remove the residual water in the horizontal pipes and water v...

Page 8: ...used hot tap note clearances in chapter 3 3 B If the unit is to be installed on a combustible surface use the enclosed heat shield see Fig 5 Danger The top of the kit will get hot due to the flue gases Install away from children Ref Description Min distances A Directly below or from an opening operable windows doors and any fresh air openings 4 ft B C D From any adjacent wall or tall shruberry 4 f...

Page 9: ...unting screws Use mounting template for proper screw location B Locate head of screw in the key hole of the top mounting bracket Vent Safety System The AQ125 BO will shut down if the intake or exhaust louvers on the vent cap are blocked for any reason see troubleshooting section on page 17 ...

Page 10: ...icated on the rating plate and in the manual for altitude up to 2000 feet 660 meters above sea level On appliances being installed above 2000 ft 660 meters elevation the inlet gas pressure should be set at installation to the value shown below Note The gas pressures specified below refer to pressures taken at the pressure tap on the gas inlet pipe just above the regulator See chapter 3 6 for measu...

Page 11: ...2 18 15 14 12 11 11 10 9 8 8 7 6 3 8 0 493 72 49 40 34 30 27 25 23 22 21 18 17 15 14 1 2 0 622 132 92 73 63 56 50 46 43 40 38 34 31 28 26 3 4 0 824 278 190 152 130 115 105 96 90 84 79 72 64 59 55 1 1 049 520 350 285 245 215 195 180 170 160 150 130 120 110 100 1 1 4 1 380 1050 730 590 500 440 400 370 350 320 305 275 250 225 210 1 1 2 1 610 1600 1100 890 760 670 610 560 530 490 460 410 380 350 320 2...

Page 12: ...aterials are not recommended for connecting directly to the water heater Keep water inlet and outlet pipes to no less than 12 7mm diameter to allow the full flow capacity It is recommended that all water piping below the heater be properly insulated to avoid heat loss If below freezing temperatures are ever anticipated where the heater is located insulation material is required and must be capable...

Page 13: ...med Warning This heater must be electrically grounded in accordance with the most recent edition of the National Electrical Code NFPA 70 In Canada all electrical wiring to the heater should be in accordance with local codes and the Canadian Electrical Code CSA C22 1 Part 1 Do not rely on the gas or water piping to ground the metal parts of the heater Warning The heater is equipped with freeze prev...

Page 14: ...r window 6 Slide the gas valve button to the right under the mark 7 Fully depress gas valve button and light pilot by pushing the button marked This step may have to be repeated B 8 Observe the pilot flame through the peephole The gas valve button should be held down for at least 15 seconds with pilot burning When the gas valve button is released the pilot should continue to burn If the gas valve ...

Page 15: ...e knob clockwise will raise the temperature and lower the activation rate Fig 11 Gas control slide button The gas control slide button adjusts temperature by adjusting how much gas is allowed to flow to the burners As the slide is adjusted to the left the output temperature will lower with the lowest setting being the one flame position The hottest position is the three flame position all the way ...

Page 16: ...ning pilot assembly Disconnect the flame sensor rod cable and the igniter cable by pulling gently down Remove two screws hold ing pilot assembly in place Loosen compression fitting and remove pilot assembly Note The orifice sits on top of the compression fitting DO NOT LOSE Polish flame sensor rod and igniter tip with emery cloth Clean out pilot assembly and orifice with carburetor cleaner If heat...

Page 17: ...lame now remains on the ECO may be defective 6 Have a licensed gas technician verify the proper operation of the thermocouple by measuring the millivoltage from the thermocouple lead to ground The expected reading is 24mVDC or greater 6 4 Burner do not ignite with water flow 1 Verify the pilot is lit 2 Turn temperature adjustment knob all the way clockwise Turn hot water faucet to full on position...

Page 18: ...re range setting recommended is 30 50 psi 2 07 3 45 bar Confirm that the pressure tank is not water logged 5 Service water valve See chapter 5 2 for intervals and instructions 6 ECO overheat sensor tripped due to overheating re ignite the appliance 10 minutes later If it happens again contact your service person 6 7 Water is not hot enough 1 Adjust the temperature per chapter 4 4 2 Shut off instal...

Page 19: ...list 7 1 Interior components Fig 12 Functional scheme 1 Heat exchanger 2 Pilot assembly 3 Burner manifold gas pressure test nipple 4 Main gas burner 5 Pilot gas tubing 6 on off switch 7 Water valve 8 Gas control slide 9 Electronic control box 10 Temperature adjustment selector 1 2 5 11 10 8 7 3 4 9 6 ...

Page 20: ...8 716 473 147 20 Interior components and diagram parts list 7 2 Components diagram Fig 13 Components Diagram ...

Page 21: ... 200 173 0 LP 13 Sparking plug 8 708 107 002 0 14 Strainer 8 700 507 055 0 15 Pipe Pilot gas 8 700 707 320 0 16 Gas valve 8 707 021 090 0 NG 16 Gas valve 8 707 021 091 0 LP 17 Magnetic unit 8 707 201 012 0 18 Piezo igniter 8 708 108 040 0 19 Nut 8 743 301 025 0 20 Cable 8 704 401 023 0 21 Water valve 8 707 002 708 0 22 Cover 8 705 500 101 0 23 Sleeve 8 700 306 114 0 24 Diaphragm C 8 700 503 053 0 ...

Page 22: ...th built in water flow limiters They will give you the same comfort level while saving water B Define the temperature you want This way you have the precise water flow needed mixing cold water to regulate temperature will increase the water flow with consequent waste of water For increased safety shut off the appliance from the main water supply if your are staying away from home for a considerabl...

Page 23: ... to supplying the replacement part s CEC will provide ground service delivery for these parts Expedited or upgraded shipping will be charged to the customer Service Labor Costs This warranty does not cover any labor costs associated with service removal or re installation of part s All such costs must be borne by the Purchaser Additionally this warranty does not cover any labor costs associated wi...

Page 24: ...___ ___ ___ 8 digit serial number is located on rating plate on right side panel Gas Pressure Reading Static__________ Operating__________ Building Water Pressure __________ Range if on Well system __________ Average Winter Temperature __________ Average Summer Temperature __________ Installing Company _____________________________________________ Installer name ___________________________________...

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