Page 2 - Index
6 720 608 782 2 Index Index 1 Warning 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....
Page 3 - Warning; For your safety
6 720 608 782 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. FCC:This device complies with Part 15 of the FCC rules.Operation is subject to the following two conditions: (1...
Page 4 - Appliance details; Features
6 720 608 782 4 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 quali...
Page 5 - Rating plate
6 720 608 782 Appliance details 5 Call Bosch Water Heating through Bosch thermotechnology corporation for conversioninstructions. Voltage 120 V AC (60 Hz) nominal Amperage Idle - 40 mAOperation - ≤ 2.5 A Noise 45 - 65 db (A) Safety devices • Flame failure device (ionization flame rod sensor) • Press...
Page 6 - Loosen the two screws; To remove combustion cover (service only); Remove the combustion cover; The National Fuel
6 720 608 782 6 Appliance details To remove front cover B Loosen the two Philips head screws located onbottom 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...
Page 7 - Dimensions and Minimum installation clearances; Dimensions
6 720 608 782 Appliance details 7 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 8 - Installation instructions; Tools required for installation; Vent material and specifications; lenght
6 720 608 782 8 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 ...
Page 9 - Table 3 Terminator Part Numbers
6 720 608 782 Installation instructions 9 upwards towards termination ¼" for every foot ofhorizontal length, to prevent the pooling of condensate,and be supported at 4 foot intervals with overheadhangers. Exception: horizontal run between last elbowand termination must pitch down to termination1...
Page 10 - Description
6 720 608 782 10 Installation instructions Recommended exhaust vent terminator position Fig. 10 * 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 exha...
Page 12 - Fig. 15 Condensate drain installation; Room sealed installation (TWIN PIPE SYSTEM); Table 7 Approved Condensate Drain Part Numbers
6 720 608 782 12 Installation instructions 3.3.2 Condensate drain requirements A condensate drain must be installed under thefollowing conditions: • All vertical terminating vent installations • Horizontal terminating vent installations where the total equivalent exhaust vent length is greater than ...
Page 13 - : reduce 2.5 ft for each 90° elbow used after the; Determining installation adjustment; Approved terminators must; TWIN PIPE; Intake; Maximum combined intake and exhaust; fan speed
6 720 608 782 Installation instructions 13 Fig. 18 Open combustion installation (SINGLE PIPE SYSTEM) Not recommended in cold climate areas, seechapter 3.4, page 15. Fig. 19 Connecting a one piece 90 degree elbow pipe to thecombustion air inlet adaptor is required. This willprevent debris or objects ...
Page 15 - Combustion air requirements; Twin pipe; In areas where outside
6 720 608 782 Installation instructions 15 signage installed in accordance with the provisions of248 CMR 5.08(2)(a)1 through 4. (b) EXEMPTIONS: The following equipment is exemptfrom 248 CMR 5.08(2)(a)1 through 4: 1. The equipment listed in Chapter 10 entitled"Equipment Not Required To Be Vented&...
Page 16 - Heater placement and clearances; Mounting; Mounting installation
6 720 608 782 16 Installation instructions below for providing adequate combustion air for thewater heater as well as any other appliances that mayconsume air in the space. Always follow local codes ifthey are more stringent. This Installation Manual specifies the minimum exhaustvent length (Fig. 8,...
Page 17 - Fig. 22 Distance between support boards; Gas piping & connections; Do not install this appliance
6 720 608 782 Installation instructions 17 If wall is sheathed with plaster or drywall, it isrecommended that two support boards, either 1”x4” or1/2" (minimum) plywood first be attached across a pairof studs, see Fig. 22. B Secure the wall mounting bracket provided with the heater to the wall su...
Page 18 - GAS LINE SIZING
6 720 608 782 18 Installation instructions INSTALLATION CODES and/or local installationcodes. GAS CONNECTIONS B Install a manual gas shut off valve on the gas supply line within easy reach of the appliance. B Install a union when connecting gas supply. B The minimum internal diameter required forany...
Page 19 - FOR NATURAL GAS; corrugated) Tubing in Thousands of BTU per Hour of; FOR LP GAS
6 720 608 782 Installation instructions 19 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. 27 Follow boxed num...
Page 20 - This heater is not approved; HOT; pH
6 720 608 782 20 Installation instructions 3.9 Water connections B When facing the heater, the ¾” cold connection is onthe bottom right and the hot connection is on thebottom left. Centrally locating the water heater isrecommended to keep hot water distribution timeseven throughout the structure. Fi...
Page 21 - Connecting the pressure relief valve (PRV); No valve is; No; Recirculation application; Fig. 30 Recirculation application; Ariston Minitank
6 720 608 782 Installation instructions 21 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 22 - Measuring gas pressure; Minimum inlet gas pressure under full operation; Static; Operating; Gas Pressure Reading (see Chapter
6 720 608 782 22 Installation instructions 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. 32). B Loose...
Page 23 - Electrical connections; Electrical power supply; Fig. 33 Connecting power supply cord; Position of the fuses in control unit; Remove the three screws on front of the control unit.
6 720 608 782 Electrical connections 23 4 Electrical connections 4.1 Electrical power supply The GWH 2400 ES requires an electrical power supplyfrom a 120VAC / 60Hz circuit (with a dedicated outlet)and must be properly grounded.The heater is wired as shown in the wiring diagram(chapter 9, Fig. 58). ...
Page 24 - Operation instructions; LCD Display functions; Do not use any cleaning or
6 720 608 782 24 Operation instructions 5 Operation instructions Fig. 36 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. 37 Power bar indicator Fig. 38 Temperature indicator Fig. 39 Error indic...
Page 25 - WHAT TO DO IF YOU SMELL GAS; Power; On; Temperature selection; Setting the water temperature
6 720 608 782 Operation instructions 25 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 26 - Fig. 45 Remote control; Operation; Programming “Program” function; Fig. 49 “Program” key; Memorizing selected temperature; Locked condition; Fig. 50 Locked condition
6 720 608 782 26 Operation instructions 5.5 Use of optional remote control accessory (part no. TSTAT2) Fig. 45 Remote control The wireless remote control accessory (Fig. 70,component 13) and the temperature selector buttonson the front of the water heater operate identically.Contact your distributor...
Page 27 - Maintenance and service; • Venting system - inspect inside of flue pipe for any; • In areas where the water supply has a high mineral; Winterizing for seasonal use; Always turn off the electrical; Annual maintenance table; Annual maintenance
6 720 608 782 Maintenance and service 27 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 28 - Mineral scale build-up; Descaling using a pump; Adjusting CO; The CO
6 720 608 782 28 Maintenance and service such as anti-freeze is not permitted as they may causedamage to the water heater's internal components. 1. Press ON/OFF switch on the water heater to turn OFF the heater and unplug power supply cord. Thedisplay should be blank. 2. Shut off gas supply to heate...
Page 29 - Fig. 53 Measuring port; (combustion cover must be
6 720 608 782 Maintenance and service 29 adjusting CO 2 until pressure is at or above these levels, but not to exceed 10.5” WC for Natural Gas and 13” WC for Propane. A. Once Gas Pressure is adequate B Press ON/OFF button to turn off the heater. B Remove brass flat head screw on the exhaust collaras...
Page 30 - Fig. 55 Adjusting P1 CO; values. Changes in these inputs can result in
6 720 608 782 30 Maintenance and service Final Readings P2 CO 2 Reading: % CO 2 P1 CO 2 Reading: % CO 2 Fig. 55 Adjusting P1 CO 2 level Fig. 56 Adjusting P2 CO 2 level CO 2 range (%) Max. CO level (measured) Nat. Gas max. input P1 6.9 % - 7.5 % < 250 ppm min. input P2 2.3 % - 2.6 % < 60 ppm LP...
Page 31 - Program values; Maximum Power
6 720 608 782 Maintenance and service 31 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 32 - Control board diagnostics; Diagnostic menu
6 720 608 782 32 Maintenance and service 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 33 - Fan speed adjustment; Exhaust
6 720 608 782 Maintenance and service 33 6.7 Fan speed adjustment Installation adjustment: Flue pipe length setting for minimum power - P2. After installing the GWH 2400 ES, the minimum powerfan speed must be selected to compensate for variationin vent pipe length. Total vent length calculation B De...
Page 34 - button and press; Mode; Table 19Fan speed adjustment
6 720 608 782 34 Maintenance and service 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. 57 B As soon as '188' is displayed, release "Program"button , and the display should read P2. B Press or ...
Page 35 - Troubleshooting; Introduction
6 720 608 782 Troubleshooting 35 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 36 - Low water flow/pressure
6 720 608 782 36 Troubleshooting the 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 for help in correcting acrossover. Failing single le...
Page 37 - adjustments must be done by a certified
6 720 608 782 Troubleshooting 37 out of adjustment. This will result in unstable burnerflames and noise. Ensure gas pressure is inaccordance with specifications in section 3.12, page22 Measuring Gas Pressure. A gas pressure readingis needed to proceed further. Contact your originalinstaller or a loc...
Page 38 - Problem solving; Error code diagnostics; Display; Fault in the flue gas limiter.; * By installer or service technician only.
6 720 608 782 38 Problem solving 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. 63 , page 46 ). Go to steps two and three to dete...
Page 40 - page; Clean inlet filter screen per chapter
6 720 608 782 40 Problem solving 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. 69 , page 52 ). 2. Check red wire connections at outlet temperature senso...
Page 42 - Electrical diagram; Fig. 58 Electrical scheme
6 720 608 782 42 Electrical diagram 9 Electrical diagram Fig. 58 Electrical scheme 1 Intlet water temperature sensor 2 Outlet water temperature sensor 3 Exhaust temperature sensor 4 Cascading output connection 5 Cascading input connection 6 Ionization sensor 7 Water flow sensor 8 Flue gas limiter 9 ...
Page 43 - Sensor resistance charts; Outlet temperature sensor characteristics
6 720 608 782 Sensor resistance charts 43 10 Sensor resistance charts Fig. 59 Fig. 60 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 44 - Back Flow characteristics
6 720 608 782 44 Sensor resistance charts Fig. 61 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 45 - GWH 2400 ES Functional scheme; Fig. 62 Functional scheme
6 720 608 782 GWH 2400 ES Functional scheme 45 11 GWH 2400 ES Functional scheme Fig. 62 Functional scheme
Page 46 - Interior components diagram and parts list; Interior components
6 720 608 782 46 Interior components diagram and parts list 12 Interior components diagram and parts list 12.1 Interior components Fig. 63 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 47 - Fig. 64 Appliance overview
6 720 608 782 Interior components diagram and parts list 47 Fig. 64 Appliance overview
Page 48 - Components diagram; Fig. 65 Components Diagram
6 720 608 782 48 Interior components diagram and parts list 12.2 Components diagram 12.2.1 Group 1 Fig. 65 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 49 - Fig. 66 Components Diagram
6 720 608 782 Interior components diagram and parts list 49 12.2.2 Group 2 Fig. 66 Components Diagram 1 3 2 4 5 6 7 8 9 6720902974.AA JF Item Description Reference 1 Heat exchanger 8 705 406 356 2 Heat exchanger top gasket 8 704 701 052 3 Flue gas collector 8 705 700 153 4 Overheat sensor (ECO) 8 70...
Page 50 - Fig. 67 Components Diagram
6 720 608 782 50 Interior components diagram and parts list 12.2.3 Group 3 Fig. 67 Components Diagram 15 14 1 3 4 6 7 8 2 12 9 10 11 13 16 17 5 6720902975.AA JF Item Description Reference 1 Main burner 8 708 120 642 2 Burner gasket 8 704 701 087 3 Primary fan 8 707 204 071 4 Backflow temperature sen...
Page 51 - Fig. 68 Components Diagram
6 720 608 782 Interior components diagram and parts list 51 12.2.4 Group 4 Fig. 68 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 52 - Fig. 69 Components Diagram
6 720 608 782 52 Interior components diagram and parts list 12.2.5 Group 5 Fig. 69 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 8 700 715 392 6 Temper...
Page 53 - Fig. 70 Components Diagram
6 720 608 782 Interior components diagram and parts list 53 12.2.6 Group 6 Fig. 70 Components Diagram 14 1 2 3 7 6 9 5 12 15 13 10 11 4 6720608782-08.1AL Item Description Reference 1 Control unit 8 707 207 296 2 Fuse T2.5A 1 904 521 342 3 Fuse T1.6A 8 700 609 008 4 Power supply cables 8 704 401 371 ...
Page 54 - Protecting the environment; Packing
6 720 608 782 54 Protecting the environment 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 55 - Limited Warranty
6 720 608 782 Limited Warranty 55 14 Limited Warranty General Aquastar water heaters are warranted by theManufacturer (BOSCH) through Bosch thermotechnology corporation. Bosch thermotechnology corporation will furnish a replacement heat exchanger and will furnish areplacement of any other part which...
