Page 2 - Index
6 720 608 542 2 Index Index 1 Warning 3 2 Appliance details 4 2.1 Features 4 2.2 Specifications (Technical data) 5 2.3 Unpacking the heater 6 2.4 General rules to follow for safe operation 7 2.5 Dimensions and Minimum installation clearances 8 3 Installation instructions 9 3.1 Tools required for ins...
Page 3 - Warning; For your safety
6 720 608 542 Warning 3 1 Warning For your safety Do not store or use gasoline or other flammable,combustible or corrosive vapors and liquids in thevicinity of this or any other appliance. Warning: Carefully plan where you install the heater. Correct combustionair supply and flue pipe installation a...
Page 4 - Appliance details; Features; HOT; BURN; D A N G E R
6 720 608 542 4 Appliance details 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 undesiredop...
Page 6 - Unpacking the heater; Rating plate; To remove front cover; Loosen the two screws; To remove combustion cover (service only); Remove the combustion cover
6 720 608 542 6 Appliance details 2.3 Unpacking the 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 cov...
Page 8 - Dimensions and Minimum installation clearances; Dimensions; BACK; Table 1 Minimum clearances
6 720 608 542 8 Appliance details 2.5 Dimensions and Minimum installation clearances 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 ...
Page 9 - Installation instructions; Tools required for installation; Vent material; Material; Table 2 Venting Specifications
6 720 608 542 Installation instructions 9 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 ...
Page 10 - ” stainless steel pipe; 5 degree elbow; Company
6 720 608 542 10 Installation instructions Horizontal venting systems only: An optional stainless concentric vent/air intake termina-tion can be used to provide only one penetration point through the exterior wall (see Fig. 8, 9 & 10). The con-centric vent/air intake kit can be ordered from your...
Page 11 - Air intake or; Table 6 Maximum allowable straight pipe length
6 720 608 542 Installation instructions 11 Condensate drain requirements An external condensate drain (not supplied with theheater) must be installed under the followingconditions: • All vertical terminating vent installations. • Horizontal terminating vent installations where the total linear vent ...
Page 12 - Table 7
6 720 608 542 12 Installation instructions Required direct vent terminal clearances (twin pipe / concentric penetration) Fig. 11 * For clearances not specified in ANSI Z223.1 / NFPA 54 or CSA-B149.1, one of the following shall be indicated:a) A minimum clearance value determined by testing in accord...
Page 13 - Table 8
6 720 608 542 Installation instructions 13 Required other than direct vent terminal clearances (single pipe penetration) Fig. 12 * For clearances not specified in ANSI Z223.1 / NFPA 54 or CSA-B149.1, one of the following shall be indicated:a) A minimum clearance value determined by testing in accord...
Page 14 - Fig. 13 Horizontal side wall venting installation (single
6 720 608 542 14 Installation instructions 3.3.3 Venting configuration examples Below are approved examples of horizontalventing installations. Fig. 13 Horizontal side wall venting installation (single pipe penetration)* * Warning: for non-freezing climates only! Important: Note: Pitch horizontal ru...
Page 16 - Fig. 21 Condensate drain installation (combustion air; ProTech; Table 9 Approved Condensate Drain Part Numbers
6 720 608 542 16 Installation instructions 3.3.5 Condensate drain installation Note: Do not install condensate drain in areas where it may freeze. 1. Install condensate drain as close to heater as possi- ble. 2. Use 3/8" ID high temperature silicone tube to con- nect to condensate drain port. Do...
Page 17 - Exhaust; Table 11 Determining vent length combination exam-
6 720 608 542 Installation instructions 17 3.3.6 Fan speed adjustment IMPORTANT! Installation adjustment: After installing the water heater, the fan speed values forminimum power (P2) and maximum power (P1) mayneed adjustment due to variations in altitude and ventpipe length.Failure to make necessar...
Page 18 - Table 12 Fan speed adjustment
6 720 608 542 18 Installation instructions Adjusting minimum power fan speed (P2) To select fan speed: B Press ON/OFF button into OFF. B Press and hold "Program" button and press ON/OFF button to turn appliance ON. Fig. 22 B As soon as '188' is displayed, release "Program"button , an...
Page 19 - REQUIREMENTS
6 720 608 542 Installation instructions 19 Attention residents of the Commonwealth of Massachusetts: In the Commonwealth of Massachusetts the followingregulation went into effect on 12/30/2005: (a) For all side wall horizontally vented gas fueledequipment installed in every dwelling, building orstru...
Page 20 - Combustion air requirements; Twin pipe and Concentric pipe
6 720 608 542 20 Installation instructions 3.4 Combustion air requirements Twin pipe and Concentric pipe The water heater is designed as a sealed combustionappliance. It is recommended that the combustion airbe provided from the outside by a dedicated pipe (twinpipe) or by connecting to the concentr...
Page 21 - Fig. 24 Distance between support boards
6 720 608 542 Installation instructions 21 3.5 Proper location for installing your heater Carefully select the location of the water heater. Foryour safety and for proper heater operation, you mustprovide combustion air to the heater and a properexhaust vent system.Follow the guidelines below: B 1. ...
Page 22 - Fig. 25 Leveling the mounting bracket on the studs; Gas piping & connections; GAS CONNECTIONS
6 720 608 542 22 Installation instructions Fig. 25 Leveling the mounting bracket on the studs Fig. 26 Mounting the heater 3.8 Gas piping & connections Before connecting the gas supply, check the ratingplate on the right side of the heater to be sure that theheater is rated for the same gas to wh...
Page 23 - GAS LINE SIZING
6 720 608 542 Installation instructions 23 Once connections are made, check for gas leaks at alljoints. Apply some gas leak detection solution to all gasfittings. Bubbles are a sign of a leak. A combustible gasdetector may also be used to detect for leaks. GAS LINE SIZING The gas supply piping for a...
Page 24 - FOR NATURAL GAS; FOR LP GAS
6 720 608 542 24 Installation instructions 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 dropof 0.3” in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands. Fig. 29 Follow boxed num...
Page 25 - Water connections
6 720 608 542 Installation instructions 25 3.9 Water connections B When facing the heater, the ¾” cold connection is on the bottom right and the hot connection is on the bot-tom left. Centrally locating the water heater is recom-mended to keep hot water distribution times even throughout the structu...
Page 26 - No; Domestic hot water recirculation; Fig. 32 Recirculation application; Ariston Minitank
6 720 608 542 26 Installation instructions Connecting the pressure relief valve (PRV) A listed pressure relief valve supplied with the heatermust be installed at the time of installation. No valve is to be placed between the PRV and the heater. No reducing coupling or other restriction may be instal...
Page 27 - Measuring gas pressure; Static; Operating
6 720 608 542 Installation instructions 27 3.12 Measuring gas pressure Confirm gas pressure upon installation. Connecting manometer B Shut off gas supply at installer supplied shutoff valvefor this water heater. B Remove front cover and locate inlet gas pressuremeasuring point (see Fig. 34). B Loose...
Page 28 - Electrical connections; Electrical power supply; Fig. 35 Connecting power supply cord; Position of the fuses in control unit; Remove the three screws on front of the control unit.
6 720 608 542 28 Electrical connections 4 Electrical connections 4.1 Electrical power supply The water heater requires an electrical power supplyfrom a 120VAC / 60Hz properly rated receptacle andmust be properly grounded.The heater is wired as shown in the wiring diagram(chapter 9, Fig. 59). Fig. 35...
Page 29 - Operation instructions; LCD Display functions; Do not use any cleaning or
6 720 608 542 Operation instructions 29 5 Operation instructions Fig. 38 1 On/Off button 2 Reset button 3 Program Key 4 LCD display 5 Up button 6 Down button 7 LED - Power On indicator or Stand-by 5.1 LCD Display functions Fig. 39 Power bar indicator Fig. 40 Temperature indicator Fig. 41 Error indic...
Page 30 - WHAT TO DO IF YOU SMELL GAS; Power; On; Temperature selection; Setting the water temperature
6 720 608 542 30 Operation instructions 5.2 For your safety read before operating your water heater A. This appliance is equipped with electronic ignition for lighting the main burner. When turning the heater on,follow these instructions exactly. B. Before operating the unit, press the On/Off button...
Page 31 - Fig. 47 Remote control; Operation; Programming “Program” function; Fig. 51 “Program” key; Memorizing selected temperature; Locked condition; Fig. 52 Locked condition
6 720 608 542 Operation instructions 31 5.5 Use of optional remote control accessory (part no. TSTAT2) Fig. 47 Remote control The wireless remote control accessory (Fig. 71,component 13) and the temperature selector buttonson the front of the water heater operate identically.Contact your distributor...
Page 32 - Maintenance and service; Annual maintenance; Winterizing for seasonal use; Table 16 Annual maintenance
6 720 608 542 32 Maintenance and service 6 Maintenance and service The unit should be checked once a year by a gastechnician. If repairs are needed, the repairs should bedone by a gas technician. 6.1 Annual maintenance (To remove front cover, see page 6.) Venting System • Venting system - inspect in...
Page 33 - Mineral scale build-up; Descaling using a pump; Adjusting CO; The CO
6 720 608 542 Maintenance and service 33 space which is likely to experience freezingtemperatures, all water must be drained from the heater.If precautions are not taken, resulting damage will notbe covered under the warranty. NOTE: Use of agentssuch as anti-freeze is not permitted as they may cause...
Page 34 - Fig. 55 Measuring port; (combustion cover must be
6 720 608 542 34 Maintenance and service Static Gas Pressure: “ WC P1 Operating Pressure: “ WC The P1 minimum operating gas pressure is 3.5" WC for Natural Gas and 8" WC for Propane. Do not proceed in adjusting CO 2 until pressure is at or above these levels, but not to exceed 10.5” WC for N...
Page 35 - Fig. 57 Adjusting P1 CO; CO
6 720 608 542 Maintenance and service 35 Final Readings P2 CO 2 Reading: % CO 2 P1 CO 2 Reading: % CO 2 Fig. 57 Adjusting P1 CO 2 level Fig. 58 Adjusting P2 CO 2 level CO 2 range (%) Max. CO level (measured) Nat. Gas max. input P1 7.5 % - 8.1 % < 250 ppm min. input P2 2.3 % - 2.6 % < 60 ppm LP...
Page 36 - Program values; Table 18 Program values, factory default settings and ranges.
6 720 608 542 36 Maintenance and service 6.5 Program values This section describes details on programming theappliance. For most applications the factory defaultvalues will robust and stable operation. Only adjust thefactory settings if the installation requires changes asindicated in the appropriat...
Page 37 - Control board diagnostics; Diagnostic menu
6 720 608 542 Maintenance and service 37 6.6 Control board diagnostics 1. Turn on/off switch on water heater to off (O) position. 2. Press and hold the program ( ) button while turning the on/off switch to the on (I) position. Thedisplay will cycle through a startup procedureincluding the software v...
Page 38 - Troubleshooting; Introduction
6 720 608 542 38 Troubleshooting 7 Troubleshooting 7.1 Introduction Many of the questions customers ask regardingoperation of this unit can be answered by following thetroubleshooting steps as outlined below. Visit our website at www.boschhotwater.com for more detailedtroubleshooting and service bul...
Page 39 - Low water flow/pressure
6 720 608 542 Troubleshooting 39 heater. Then open all of the hot water taps served bythe heater. Wait 10 minutes and check all taps forwater flow. There should be no water flowing. Anycontinuous flow of water, small or large, indicates acrossover and must be corrected. Consult aprofessional plumber...
Page 40 - Lack of adequate gas pressure. Inadequate gas
6 720 608 542 40 Troubleshooting 5. Lack of adequate gas pressure. Inadequate gas pressure will cause the fuel-to-air mixture (CO 2 ) to be out of adjustment. This will result in unstable burnerflames and noise. Ensure gas pressure is inaccordance with specifications in section 3.12, page27 Measurin...
Page 41 - Problem solving; Error code diagnostics; Display; * By installer or service technician only.
6 720 608 542 Problem solving 41 8 Problem solving 8.1 Error code diagnostics i To remove error code from the display, press the reset button. Display Cause Solution Fault in the flue gas limiter. 1. Check continuity of the flue gas limiter (see Fig. 64 , page 49 ). Go to steps two and three to dete...
Page 43 - page
6 720 608 542 Problem solving 43 Over-temperature detected byoutlet temperature sensor on hotwater pipe.Temperature > 185 °F 1. Check that the sensor is firmly attached to the vertical section ofthe hot water pipe (see Fig. 70 , page 55 ). 2. Check red wire connections at outlet temperature senso...
Page 45 - Electrical diagram; Fig. 59 Electrical scheme
6 720 608 542 Electrical diagram 45 9 Electrical diagram Fig. 59 Electrical scheme 1 Intlet water temperature sensor 2 Outlet water temperature sensor 3 Backflow temperature sensor 4 Cascading output connection 5 Cascading input connection 6 Ionization sensor 7 Water flow sensor 8 Flue gas limiter 9...
Page 46 - Sensor resistance charts; Outlet temperature sensor characteristics
6 720 608 542 46 Sensor resistance charts 10 Sensor resistance charts Fig. 60 Fig. 61 Outlet temperature sensor characteristics 3 2 3 7 4 2 4 7 5 2 5 7 6 2 6 7 7 2 7 7 8 2 8 7 9 2 9 7 10 2 10 7 112 117 12 2 12 7 13 2 13 7 14 2 14 7 15 2 15 7 16 2 16 7 17 2 17 7 18 2 18 7 19 2 19 7 2 0 2 2 0 7 2 12 2...
Page 47 - Back Flow characteristics
6 720 608 542 Sensor resistance charts 47 Fig. 62 Back Flow characteristics 3 2 3 7 4 2 4 7 5 2 5 7 6 2 6 7 7 2 7 7 8 2 8 7 9 2 9 7 10 2 10 7 112 117 12 2 12 7 13 2 13 7 14 2 14 7 15 2 15 7 16 2 16 7 17 2 17 7 18 2 18 7 19 2 19 7 2 0 2 2 0 7 2 12 2 17 2 2 2 2 2 7 2 3 2 2 3 7 2 4 2 2 4 7 2 5 2 2 5 7 ...
Page 48 - GWH 2700 ES Functional scheme; Fig. 63 Functional scheme
6 720 608 542 48 GWH 2700 ES Functional scheme 11 GWH 2700 ES Functional scheme Fig. 63 Functional scheme
Page 49 - Interior components diagram and parts list; Interior components
6 720 608 542 Interior components diagram and parts list 49 12 Interior components diagram and parts list 12.1 Interior components Fig. 64 Components 1 Flue gas collector 2 Heat exchanger 3 Flame sensor 4 Primary fan (Mixer) 5 Outlet temperature sensor 6 LCD display 7 On/Off button 8 Reset button 9 ...
Page 50 - Fig. 65 Appliance overview
6 720 608 542 50 Interior components diagram and parts list Fig. 65 Appliance overview
Page 51 - Components diagram; Fig. 66 Components Diagram
6 720 608 542 Interior components diagram and parts list 51 12.2 Components diagram 12.2.1 Group 1 Fig. 66 Components Diagram 9 9 8 5 1 2 3 6 7 9 10 12 9 14 16 17 11 13 15 15 4 6720902973.AA JF Item Description Reference 1 Front cover 8 705 431 286 2 Cover shield 8 705 506 862 3 Trade mark badge 8 7...
Page 52 - Fig. 67 Components Diagram
6 720 608 542 52 Interior components diagram and parts list 12.2.2 Group 2 Fig. 67 Components Diagram 1 3 2 4 5 6 7 8 9 6720902974.AA JF Item Description Reference 1 Heat exchanger 8 705 406 422 2 Heat exchanger top gasket 8 704 701 052 3 Flue gas collector 8 705 700 153 4 Overheat sensor (ECO) 8 70...
Page 53 - Fig. 68 Components Diagram
6 720 608 542 Interior components diagram and parts list 53 12.2.3 Group 3 Fig. 68 Components Diagram 15 14 1 3 4 6 7 8 2 12 9 11 13 16 17 5 6720902975.AA JF Item Description Reference 1 Main burner 8 708 120 699 2 Burner gasket 8 704 701 087 3 Primary fan 8 707 204 071 4 Backflow temperature sensor...
Page 54 - Fig. 69 Components Diagram
6 720 608 542 54 Interior components diagram and parts list 12.2.4 Group 4 Fig. 69 Components Diagram 9 2 14 1 3 4 5 6 7 8 11 11 12 13 10 6720608158-73.1AL Item Description Reference 1 Gas valve 8 707 021 019 2 Pressure tapping 8 703 404 219 3 Washer 8 700 203 041 4 Pressure balance tube 8 700 703 1...
Page 55 - Fig. 70 Components Diagram
6 720 608 542 Interior components diagram and parts list 55 12.2.5 Group 5 Fig. 70 Components Diagram Item Description Reference 1 Water valve with engine 8 708 505 024 2 O-ring 8 700 205 147 3 Cold water pipe 8 700 715 394 4 Pipe connection clip 8 701 201 028 5 Hot water pipe 8 700 715 469 6 Temper...
Page 56 - Fig. 71 Components Diagram
6 720 608 542 56 Interior components diagram and parts list 12.2.6 Group 6 Fig. 71 Components Diagram 15 1 2 3 7 6 9 5 11 13 16 14 10 12 8 4 6720902978.AA JF Item Description Reference 1 Control unit 8 707 207 257 2 Fuse T2.5A 1 904 521 342 3 Fuse T1.6A 8 700 609 008 4 Power supply cables 8 704 401 ...
Page 57 - Protecting the environment; Packing
6 720 608 542 Protecting the environment 57 13 Protecting the environment Packing The packing box may be fully recycled as confirmed bythe recycling symbol . Components Many parts in the heater can be fully recycled in the endof the product life. Contact your city authorities forinformation about th...
Page 58 - Limited Warranty
6 720 608 542 58 Limited Warranty 14 Limited Warranty General Aquastar water heaters are warranted by theManufacturer (BOSCH) through Bosch Thermotechnology Corp. . Bosch thermotechnology corporation will furnish a replacement heat exchanger and will furnish areplacement of any other part which fail...
Page 60 - BOSCH
6720608542 © 2009 Bosch Thermotechnology Corp.,Londonderry, N H all rights reserved Replacement Parts available from: Bosch Termotecnologia SA Estrada de Cacia 3801 - 856 Aveiro - PORTUGAL BOSCH THERMOTECHNOLOGY CORP. 50 Wentworth AvenueLondonderry, NH 03053Tel. 866-330-2730www.boschhotwater.com Ins...