940 ES INDOOR MODEL Temperature Modulated with Electronic Ignition Suitable for heating potable water only and space heating (Intended for variable flow applications) 940 ES - Natural Gas 940 ES - Liquefied Petroleum (LP) Gas 6 720 644 930 (2010/09) US Warning: If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or death.
Index Index 1 Warning 3 2 2.1 2.2 2.3 2.4 2.
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.
Appliance details Warning: If a relief valve discharges periodically, this may be due to thermal expansion in a closed water supply system. Contact the water supplier or local plumbing inspector on how to correct this situation. Do not plug the relief valve. FCC: This device complies with Part 15 of the FCC rules.
Appliance details • Real-time diagnostics informational purposes for troubleshooting/ • LCD Display with backlight 2.2 Specifications (Technical data) Approved in US/Canada • On/Off and Temperature control switches Capacity • Reset button Maximum flow rate: 7.15 GPM (27 l/min) at a 45°F (25°C) rise. • Program button (Selectable temperature default) • Failure codes for easy diagnostics and repair • Easily removable one-piece cover • Built in freeze prevention.
Appliance details • 940 ES Dimensions • Depth (in): 11¼” (286 mm) • Width (in): 17 7 /8 ” (452 mm) • Height (in): 30½” (775 mm) • Bracket for wall hanging the heater • Exhaust vent adaptor (with 4 screws and gasket provided) • Weight: 67 pounds (30.5 kg). • Combustion air inlet adaptor (with 3 screws and gasket provided) Gas types • Installation manual (manual can be downloaded at www.boschpro.com) Natural Gas. LP Gas. Voltage • Product registration card.
Appliance details B Lift front cover panel upward and remove. B B Fig. 4 Remove the front cover To remove combustion cover (service only) B Open the four clips and remove the combustion cover see Fig. 5. B B B B 6720644956-11.1V Fig. 5 Remove the combustion cover 2.4 General rules to follow for safe operation bathrooms, bedrooms and occupied rooms that are normally kept closed. See chapter 3.3 (page 9).
Appliance details Dimensions and Minimum installation clearances 6 ½" 4 1 16" 5 ¼" 16" 2 1 16 16" 2 55 16 6 5 16" 2 ¾" 2.5 11 ¼" 7 8 " 5 ¼" 30 ½" 17 1 2 5 + reset 6 P 7 3 5 ¼" 4 6720608158-04.2AL Fig. 6 1 2 3 4 5 6 7 Dimensions On/Off button Reset button Program key Power ON or stand-by LED LCD display Up button Down button Model 940 ES TOP (A) 12” FRONT (B) 1” BACK 0” SIDES 1” FLOOR (C) 12” Table 1 Minimum clearances Fig.
Installation instructions 3 Installation instructions 3.1 Specialized tools 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. The following specialized tools may be required for installation: • Manometer • Multi-meter • Combustion Gas Analyzer. 3.
Installation instructions 6720608782-09.1Av Fig. 8 Concentric kit part # ESHCK structure. There must be no sections of vent pipe exposed to the outdoors other than the termination. Note: Listed thimbles or collars are necessary where venting passes through wall and ceiling partitions.
Installation instructions Use of elbows 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 It is recommended to limit the amount of elbows used in the exhaust and combustion air piping to reduce friction in the air flow.
Installation instructions Calculation example for 3" venting: Calculation example for 4" venting: Exhaust Exhaust System used Concentric System used Twin pipe Number of 90° elbows needed: 1 Number of 90° elbows needed: 2 Number of 45° elbows needed: 2 Number of 45° elbows needed: 2 Table 8 Table 12 Calculation of example Calculation of example Max. length 28.5’ Max. length 90° elbow reduction - 2.5’ 90° elbow reduction sub-total = 45° elbow reduction 26’ - 2.5’ Total = - 2.
Installation instructions Required direct vent terminal clearances (twin pipe / concentric penetration) 6720608836-23.1Av Fig. 11 Canadian installations1) U.S. installations2) A Clearance above grade, veranda, porch, deck or balcony 12 in. 12 in. B Clearance to window or door that may be opened 36 in. 12 in.
Installation instructions Required other than direct vent terminal clearances (single pipe penetration) 6720608836-23.1Av Fig. 12 Canadian installations1) U.S. installations2) A Clearance above grade, veranda, porch, deck or balcony 12 in. 12 in. B Clearance to window or door that may be opened 36 in.
Installation instructions 3.3.3 Venting configuration examples Below are approved examples of horizontal venting installations. 12" 4" HORIZONTAL RUN 1/4" PER FOOT DOWN TO TERMINATOR. CONDENSATE DRAIN 6720608542-02.2AL Fig. 13 Horizontal side wall venting installation (single pipe penetration) 6720608782-11.2V Fig. 15 Horizontal venting installation (concentric penetration) g tin ven ting " h 3 ven wit h 4" t f it 6 <2 0ft w <6 4" HORIZONTAL RUN DOWN TO TERMINATOR.
Installation instructions 10' MIN. RAIN CAP RAIN CAP 2' MIN. 10' MIN. 3' MIN. STORM COLLAR 2' MIN. STORM COLLAR FLASHING 3' MIN. SILICONE SEAL FLASHING FIRESTOP SUPPORT CHIMNEY 4" MIN. AIR SPACE MAY BE INSULATED IF NECESSARY FIRESTOP SUPPORT HORIZONTAL RUN 1/4" RISE/FT HANGER STRAP HOSE CLAMP ELBOW MORTAR CONDENSATE DRAIN ELBOW ELBOW HOSE CLAMP APPLIANCE CONDENSATE DRAIN 6720608158-91.2Av Fig.
Installation instructions any point. 5. Dispose of condensate according to local codes. RAIN CAP 10' MIN. 2' MIN. STORM COLLAR 3' MIN. FLASHING FIRESTOP SUPPORT 4" MIN. AIR SPACE ELBOW CONDENSATE DRAIN TEE 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.
Installation instructions Solution One The Z-flex vent termination hood is the preferred option for limiting backdraft under the following conditions (see Fig. 23): • The vent hood is only to be used in the exhaust vent piping. • To allow accessibility, damper must not be installed in an enclosed section of vent pipe. • Do not install damper in unconditioned spaces (e.g. attics) Condensation can build up while the heater is running which can later freeze and potentially block the flapper.
Installation instructions Preferred damper position for vertical terminations 3.3.7 Fan speed adjustment IMPORTANT! Installation adjustment: After installing the water heater, the fan speed values for minimum power (P2) and maximum power (P1) may need adjustment due to variations in altitude and vent pipe length. Failure to make necessary adjustments to fan speed values may result in improper operation of the appliance. Unconditioned space. Do not install damper.
Installation instructions Fan speed adjustment Natural Gas Altitude (above sea level) 0 - 2000 ft (0 - 610 m) 2000 - 4500 ft (610 - 1372 m) 4500 - 8000 ft (1372 - 2439 m) Total equivalent vent length1) Minimum power fan speed (P2) 3.5 - 32 ft 7 33 - 57 ft 8 3.5 - 32 ft Liquid propane Maximum Maximum power fan speed power fan speed (P1) (P1) No modification required No modification required 8* 48* 47* 33 - 57 ft 8* 49* 48* 3.
Installation instructions Adjusting minimum power fan speed (P2) Adjusting maximum power fan speed (P1) To select fan speed: To select fan speed: B Press ON/OFF button into OFF. B Press ON/OFF button into OFF. B Press and hold "Program" button ON/OFF button to turn appliance ON. and press B Press and hold "Program" button and press ON/OFF button to turn appliance ON. Fig. 27 Fig. 28 B As soon as '188' is displayed, release "Program" button , and the display should read P2.
Installation instructions Attention residents of the Commonwealth of Massachusetts: signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4. In the Commonwealth of Massachusetts the following regulation went into effect on 12/30/2005: (b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.
Installation instructions 3.4 Combustion air requirements Warning: In areas where outside temperatures routinely come close to freezing, sealed combustion operation is required. Use twin pipe or concentric terminations for combustion air and exhaust, 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.
Installation instructions 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.
Installation instructions 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 INSTALLATION CODES and/or local installation codes.
Installation instructions Once connections are made, check for gas leaks at all joints. Apply some gas leak detection solution to all gas fittings. Bubbles are a sign of a leak. A combustible gas detector may also be used to detect for leaks. Danger: If you have a leak, shut off the gas. Tighten appropriate fittings to stop leak. Turn the gas on and check again with a gas leak detection solution. Never test for gas leaks using a match or flame.
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 drop of 0.3” in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands. Follow boxed numbers for piping just one 940 ES (example: ¾” B.I. Natural Gas pipe for 10 ft (3.0m). will handle 278,000 btu’s (81.5 kWh). For multiple appliances combine the total maximum btu input load and then refer to applicable chart below.
Installation instructions 3.9 Water connections Warning: This heater is not approved for preheated water applications above 140°F (60°C). See chapter 3.11 for approved recirculating application. Warning: In applications where inlet water temperature can exceed 140°F (60ºC), a 3-way valve or mixing valve must be installed before the appliance to prevent water exceeding 140°F (60°C) from entering the appliance.
Installation instructions Connecting the pressure relief valve (PRV) 3.11 Domestic hot water recirculation A listed pressure relief valve must 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 installed in the discharge line. The discharge line must be a minimum of 4” above a drain and installed such that it allows complete drainage of both the PRV and the line.
Installation instructions 3.12 Space heating applications Warning: If the set point temperature is above 120°F, precautions should be taken to protect users of potable water from scalding. Warning: Ensure the primary pump is properly sized to provide adequate flow for the system heat load. i Warning: Propylene glycol may be used for freeze prevention ONLY on the space heating side of the heat exchanger. Do not use ethylene glycol (automotive antifreeze).
Installation instructions 8 18 13 17 T 5 7 12 22 16 15 1 11 21 14 9 5 20 9 10 2 3 6 9 5 4 6720644887-02.1V 19 Fig.
Installation instructions 3.13 Measuring gas pressure B Record lowest operating gas pressure reading in table 23. Confirm gas pressure upon installation. Connecting manometer B Shut off gas supply at installer supplied shutoff valve for this water heater. B Remove front cover and locate inlet gas pressure measuring point (see Fig. 42). B Loosen screw inside left test point fitting (do not remove) and connect manometer tube to test point. Remove screw completely if correct size tapping is available.
Electrical connections 4 Electrical connections 4.1 Electrical power supply 4.2 Warning: For safety reasons, disconnect the power supply cord to the heater before any service or testing is performed. 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.
Operation instructions 5 Operation instructions Fig. 46 1 2 3 4 5 6 7 5.1 On/Off button Reset button Program Key LCD display Up button Down button LED - Power On indicator or Stand-by Description LCD display Warning: Do not use any cleaning or corrosive agent to clean the window. Fig. 50 Lock indicator (only with remote control) Fig. 51 Flame indicator Fig. 47 Power bar indicator (input) Fig. 52 Solar mode indicator (see chapter 5.4, page 35) Fig. 48 Temperature indicator Fig.
Operation instructions 5.2 For your safety read before operating your water heater Warning: If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or loss of life. 5.4 Temperature selection To select output water temperature: B Press buttons temperature. or in order to reach desired A. This appliance is equipped with electronic ignition for lighting the main burner. When turning the heater on, follow these instructions exactly. B.
Operation instructions Solar mode The water heater will not ignite if inlet water temperature exceeds the set temperature on the appliance. In this condition, the solar mode indicator will show on the LCD display. See Fig. 52, page 34. Warning: In applications where inlet water temperature can exceed 140°F (60ºC), a thermostatic or mixing valve must be installed before the appliance to prevent water exceeding 140°F (60°C) from entering the appliance. control unit (Fig.
Maintenance and service Programming “Program” function Programming actions are similar for both controls (appliance control pad and wireless remote control). Caution: B Check and clean the complete water heating system once a year. B Carry out a maintenance overhaul if necessary. Immediately repair defects to avoid damage to the system. Annual maintenance table Every year Fig. 61 “Program” key 1. Inspect venting system X 2. Inspect Combustion chamber X 3. Inspect burner X 4.
Maintenance and service shutoff and supplied water shutoffs, carefully remove inlet and outlet clips on watervalve. Remove water valve to access filter. Clean or replace if damaged. Descaling • In areas where the water supply has a high mineral content (see Table 21, page 28), the heat exchanger should be periodically flushed with a descaling solution. Scale build up will shorten the life of the water heater and damage resulting from scale is not covered under warranty. Refer to section 6.
Maintenance and service 16.Reconnect electrical supply to unit, open water shutoff valves, and return the unit to service. B Insert CO2 analyzer probe into the measuring port. The tip of the probe should be in the center of the flue pipe (approx 1.5" inserted). Avoid air gaps between probe and measuring port as they can alter readings. Fig. 64 Measuring port B While holding the Program (P) button in, press the ON/OFF button to turn ON the heater (see Fig. 65).
Maintenance and service D. Returning to Service: CO2 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 Gas 1. Return slotted screw cover to original position and tighten philips screw. 2. Reinstall Torx cover. 3. Remove CO2 analyzer probe and reinstall flathead screw with gasket in exhaust collar. 4. Press ON/OFF button to turn OFF the heater and then turn ON the heater. 5. Heater is ready for normal operation. max.
Maintenance and service 6.5 Program values This section describes details on programming the appliance. For most applications the factory default values will robust and stable operation. Only adjust the factory settings if the installation requires changes as indicated in the appropriate section of this manual. Refer to chapter 6.6 Control board diagnostics (page 42) regarding how to access these P-modes. Caution: Misadjusted program values can lead to appliance malfunction, errors, and service calls.
Maintenance and service 6.6 Diagnostic menu 1. Turn on/off switch on water heater to off (O) position. B Press and hold the program ' ' button while turning the on/off switch to the on (I) position. The display will cycle through a startup procedure including the software version. B Release the ' ' button when '188' appears on the display. The display should read 'P2' when the program button is released. If not, repeat process.
Troubleshooting 7 Troubleshooting Warning: If you are unable to perform the tasks listed below, or need additional assistance please contact your original installer or licensed gas technician. i 7.1 Inside the heater it is normal to find unplugged wire connectors. These connections are for adding accessories such as cascading. Introduction Many of the questions customers ask regarding operation of this unit can be answered by following the troubleshooting steps as outlined below.
Troubleshooting mix cold water with the hot water leaving the heater. The end result is a cooler water temperature than desired. To check for a plumbing crossover, shut off the cold water supply to the water heater. Then open all of the hot water taps served by the heater. Wait 10 minutes and check all taps for water flow. There should be no water flowing. Any continuous flow of water, small or large, indicates a crossover and must be corrected.
Troubleshooting proceed further. Contact your original installer or a local certified gas technician to obtain this reading. 6. Verify proper CO2 readings per chapter 6.4, page 39. CO2 adjustments must be done by a certified gas technician with a calibrated combustion gas analyzer.
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. Temperature above 230°F (110°C) inside the cabinet. 1. Check continuity of the flue gas limiter (see Fig. 73, page 54). Go to steps two and three to determine air box temperature sensor fault and replace it. 2.
Problem solving Display (Flashing) (Flashing) Cause Solution Outlet temperature sensor not sensing expected output temperature. (Status message, not an error). 1. Check that the sensor is firmly attached to the hot water pipe (see Fig. 79, page 60). 2. Ensure that outlet temperature sensor is not placed on any bends in the hot water pipe or misreading may occur. 3. Check gas pressure. Low gas pressure may prevent the heater from reaching desired output temperature. 4. Check supply voltage.
Problem solving Display Cause Solution Cold water temperature sensor fault. 1. Check connector on wires coming from top of watervalve for a secure connection. See Fig. 73, page 54. 2. Sensor may trip if water temperature drops below 36°F to protect heater from freezing conditions Any damage due to freezing conditions is not covered under warranty. 3. Check sensor (ref. page 51, chapter 10). Backflow temperature sensor over 309°F. The appliance will close the burner and lock. 1.
Problem solving Display Cause Solution Ionization failure during operation. 1. Check gas type, see Fig. 2, page 6. 2. Check three wire connections to ignition group on the lower front of the heat exchanger are secure. 3. Check venting specifications are met. Improper venting may cause unstable burner flames and loss of flame ionization. 4. Check that the minimum power fan speed has been adjusted to the proper value. See page 20. 5. Check gas pressure, see section 3.13, page 32. 6.
Electrical diagram 9 Electrical diagram 16 20 15 13 M M 12 M E PS 11 10 19 T=104°C T=220°F 18 9 T=110°C T=230°F 8 FS 7 6 Casc. 5 input Casc. 4 output Back flow 3 2 1 17 16 ... 1 20 ... 1 21 14 JP2 JP7 JP5 JP8 JP6 22 6720608158-92.1AL Fig.
Sensor resistance charts 10 Sensor resistance charts 110 222 2 17 2 12 207 202 19 7 19 2 18 7 18 2 177 172 16 7 16 2 157 152 14 7 14 2 13 7 13 2 12 7 12 2 117 112 10 7 10 2 97 92 87 82 77 72 67 62 57 52 47 42 37 32 10 5 10 0 95 90 85 80 75 70 65 60 55 50 Temp ºC Temp ºF Outlet NTC characteristics 45 40 35 30 25 20 15 10 5 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 Resistance (Kohm) Fig.
Sensor resistance charts 155 302 297 292 287 282 277 272 267 262 257 252 247 242 237 232 227 222 2 17 2 12 207 202 19 7 19 2 18 7 18 2 17 7 17 2 16 7 16 2 15 7 15 2 14 7 14 2 13 7 13 2 12 7 12 2 117 112 10 7 10 2 97 92 87 82 77 72 67 62 57 52 47 42 37 32 150 14 5 14 0 13 5 13 0 12 5 12 0 115 110 10 5 10 0 95 90 85 80 75 70 Temp ºC Temp ºF Back Flow characteristics 65 60 55 50 45 40 35 30 25 20 15 10 5 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
Functional scheme 11 Functional scheme IDLE Water flow > 0.5 gpm (> 1.9 l/min) (see WF calc.) water tap open? See error code table NO YES Fan speed = correct Ionization = off Temp. limiter = closed Temp. sensors = ok Over heat protection = ok Appliance ready to start? YES Fan speed OK? NO NO NO waiting time of 10s passed? YES YES Start sparking Open the gas valve INPUTS: - FANSPEED - WATER TEMP.
Interior components diagram and parts list 12 Interior components diagram and parts list 12.1 Interior components Fig.
Interior components diagram and parts list Fig.
Interior components diagram and parts list 12.2 Components diagram 12.2.1 Group 1 9 16 9 15 12 9 17 13 15 14 10 5 6 8 9 7 3 2 11 4 1 6720902973.AA JF Fig.
Interior components diagram and parts list 12.2.2 Group 2 3 2 1 5 4 8 9 6 7 6720902974.AA JF Fig.
Interior components diagram and parts list 12.2.3 Group 3 5 1 2 4 3 6 9 16 13 12 8 11 7 15 14 17 6720902975.AA JF Fig.
Interior components diagram and parts list 12.2.4 Group 4 14 11 10 13 12 11 6 7 9 1 8 2 5 3 4 6720608158-73.1AL Fig.
Interior components diagram and parts list 12.2.5 Group 5 4 3 12 4 1 5 6 2 8 13 7 11 12 9 10 9 11 15 16 17 14 6720902977.AA JF Fig.
Interior components diagram and parts list 12.2.6 Group 6 4 8 5 6 7 9 10 3 2 11 1 14 15 16 12 13 6720644956-09.1V Fig. 80 Components Diagram Item Description Reference Item Description Reference 1 Control unit 8 707 207 368 9 Electrode cables 8 704 401 346 Flue gas limiter 8 700 400 032 2 Fuse T2.5A 1 904 521 342 10 3 Fuse T1.
Protecting the environment 13 Protecting the environment Packing The packing box may be fully recycled as confirmed by the recycling symbol . Components Many parts in the heater can be fully recycled in the end of the product life. Contact your city authorities for information about the disposal of recyclable products. Saving water resources: B Make sure you close all the taps after any use. Avoid leaving the taps dripping. Repair any leaking tap.
Limited Warranty 14 Limited Warranty General Service Labor Costs BOSCH PRO tankless water heaters are warranted by the Manufacturer (BOSCH) through Bosch Thermotechnology Corp. Bosch Thermotechnology Corp. will furnish a replacement heat exchanger and will furnish a replacement of any other part which fails in normal use and service within the applicable periods specified below, in accordance with the terms of this warranty. The Bosch Thermotechnology Corp.
6720644930 Installer Checklist to be completed by installer upon installation Serial Number ___ ___ ___ ___ ___ ___ ___ ___ (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 __________ Installing Company _____________________________________________ Installer name _____________________________________________ Address ________________________________________
