MODEL GWH 2700 ES NG and GWH 2700 ES LP INDOOR MODEL Temperature Modulated with Electronic Ignition Suitable for heating potable water only Not approved for space heating purposes (Intended for variable flow applications) GWH 2700 ES NG - Natural Gas GWH 2700 ES LP - Liquefied Petroleum (LP) Gas 6 720 608 542 (2009/03) 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 2.5 Appliance details Features Specifications (Technical data) Unpacking the heater General rules to follow for safe operation Dimensions and Minimum installation clearances 4 4 5 6 7 8 3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.
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: The anti freeze kit is designed to provide protection for the water heater down to approximately 5°F for short term conditions only. It will not protect the appliance in areas where the temperature is routinely expected to be below freezing. B The anti freeze kit will not protect plumbing outside the appliance from freezing. Precautions should be taken. B Always drain the water heater if it will be exposed to long term freezing conditions. See Section 6.
Appliance details 2.2 Specifications (Technical data) Approved in US/Canada Capacity Maximum flow rate: 7.15 GPM (27 l/min) at a 45°F (25°C) rise. Dimensions • Depth (in): 11¼” (286 mm) • Width (in): 17 7/8” (452 mm) • Height (in): 30½” (775 mm) • Weight: 67 pounds (30,5 kg). Maximum output Gas types 160,500 Btu/h (47.0 kW) Natural Gas. LP Gas. Converting the gas type can only be done by a certified gas technician with a calibrated CO2 analyzer.
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 cover. To remove front cover B Loosen the two Philips head screws located on bottom rear of cover (see Fig. 3). Fig. 3 Fig. 2 A B Rating plate Loosen the two screws B Lift front cover panel upward and remove.
Appliance details 2.4 General rules to follow for safe operation B 10. Failure to install heater correctly may lead to unsafe operation and void the warranty. B 1. You must follow these instructions 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 must conform with CGA B149.(1,2) INSTALLATION CODES and /or local installation codes. B 2.
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 GWH 2700 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 Tools required for installation Warning: Approved terminators must be used for inlet and exhaust vent systems to prevent rain from entering the appliance. Failure to do so may result in damage to the appliance. This failure is not covered under the manufacturer’s warranty.
Installation instructions Horizontal venting systems only: 3.3.2 An optional stainless concentric vent/air intake termination can be used to provide only one penetration point through the exterior wall (see Fig. 8, 9 & 10). The concentric vent/air intake kit can be ordered from your local wholesaler. (Part# ESHCK). Note: Vent piping and terminal used with concentric vent/air intake kit must be from the same vent pipe manufacturer.
Installation instructions Condensate drain requirements An external condensate drain (not supplied with the heater) must be installed under the following conditions: Air intake or Exhaust system # of 90° elbows 0 1 2 3 4 • All vertical terminating vent installations. 0 N/A* 26 21 16 11 • Horizontal terminating vent installations where the total linear vent length is greater than 10 feet (3.1 m).
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. ft 26 4" HORIZONTAL RUN 1/4" PER FOOT DOWN TO TERMINATOR. CONDENSATE DRAIN 6720608542-05.2AL Fig. 15 Horizontal twin pipe penetration 6720608542-02.2AL Fig.
Installation instructions 3.3.4 Vent connections B Attach the flue gas exhaust accessory (8 705 504 162) to the top of the unit (position 1) using the 4 screws and gasket provided. Fully insert stainless steel vent pipe 1.5” minimum into the accessory and tighten the clamp (position 2). i NOTE: Vent pipe must be completely vertical when inserting or gasket inside exhaust accessory can become displaced. Exhaust accessory can be removed with vent pipe attached to check gasket position. Fig.
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 possible. 2. Use 3/8" ID high temperature silicone tube to connect to condensate drain port. Do not use copper piping for any portion of the condensate drain. 3. Form a condensate trap by means of a 3" loop partially filled with water. 4.
Installation instructions 3.3.6 Fan speed adjustment Example IMPORTANT! Installation adjustment: Exhaust 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. • 7 - 3' straight sections First calculate the total equivalent vent length.
Installation instructions Natural Gas Altitude (above sea level) Total equivalent vent length1) Minimum power fan speed (P2) 5.5 - 32 ft 7 33 - 57 ft 8 5.5 - 32 ft 0 - 2000 ft (0 - 610 m) 2000 - 4500 ft (610 - 1372 m) 4500 - 8000 ft (1372 - 2439 m) 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* 5.
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 3.5 Proper location for installing your heater 3.7 Warning: before starting installation Carefully select the location of the water heater. For your safety and for proper heater operation, you must provide combustion air to the heater and a proper exhaust vent system. Follow the guidelines below: B Check that there are no loose or damaged parts inside the appliance B Confirm the gas type of the heater matches the gas supply you will be connecting the heater, see Fig.
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 GWH 2700 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. 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 supplied with the heater 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 Measuring gas pressure B Record lowest operating gas pressure reading in table 15. Confirm gas pressure upon installation. Connecting manometer B Shut off gas supply at installer supplied shutoff valve for this water heater. Gas pressures lower than 3.5" W.C. for Natural Gas or 8" W.C. for LPG will result in insufficient degree rise to the hot water being used, reduced hot water volume, possible error code faults and must be corrected. See Gas Connections, chapter 3.
Electrical connections 4 Electrical connections 4.1 Electrical power supply 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. 38 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 LCD Display functions Warning: Do not use any cleaning or corrosive agent to clean the window. Fig. 42 Lock indicator Fig. 43 Flame indicator Fig. 39 Power bar indicator Fig. 44 Remote control Fig. 40 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 5.5 Use of optional remote control accessory (part no. TSTAT2) Fig. 50 Reset button If the problem persists, contact your installer. 5.8 Program button can be used on the appliance and in the remote control. Fig. 47 Remote control The wireless remote control accessory (Fig. 71, component 13) and the temperature selector buttons on the front of the water heater operate identically. Contact your distributor to order the remote control accessory.
Maintenance and service 6 Maintenance and service Warning: Always turn off the electrical power supply, turn off the manual gas shut off valve and turn off the water shut off valves whenever servicing. 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. Pressure relief valve • Manually open the pressure relief valve to ensure proper operation.
Maintenance and service space which is likely to experience freezing temperatures, all water must be drained from the heater. If precautions are not taken, resulting damage will not be covered under the warranty. NOTE: Use of agents such as anti-freeze is not permitted as they may cause damage 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. The display should be blank. 2. Shut off gas supply to heater. 3.
Maintenance and service Static Gas Pressure: P1 Operating Pressure: “ WC “ WC The P1 minimum operating gas pressure is 3.5" WC for Natural Gas and 8" WC for Propane. Do not proceed in adjusting CO2 until pressure is at or above these levels, but not to exceed 10.5” WC for Natural Gas and 13” WC for Propane. B Record the CO2 reading in P1 below. (Analyzer reading may take several minutes to stabilize). B Press the ‘ ’ button until P2 appears. Unit will ramp down to low fire and the flow should decrease.
Maintenance and 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 max. input P1 8.7 % - 9.3 % < 250 ppm min. input P2 2.7 % - 3.0 % < 60 ppm * Values above are for climate controlled conditions. Inputs such as gas pressure, heating value of the gas, humidity and temperature of combustion air all impact CO and CO2 values.
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 37) 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 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. The display will cycle through a startup procedure including the software version. 3. 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. 7.1 Introduction Many of the questions customers ask regarding operation of this unit can be answered by following the troubleshooting steps as outlined below. Visit our web site at www.boschhotwater.com for more detailed troubleshooting and service bulletins.
Troubleshooting 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. Consult a professional plumber for help in correcting a crossover. Failing single lever faucets and mixing valves are common causes of plumbing crossovers. 8.
Troubleshooting 5. Lack of adequate gas pressure. Inadequate gas pressure will cause the fuel-to-air mixture (CO2) to be out of adjustment. This will result in unstable burner flames and noise. Ensure gas pressure is in accordance with specifications in section 3.12, page 27 Measuring Gas Pressure. A gas pressure reading is needed to 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 33.
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. 64, page 49). Go to steps two and three to determine air box temperature sensor fault and replace it. 2. Check for flue gas leakage around the top and bottom seals of heat exchanger as well as the viewing window. 3.
Problem solving Display (Flashing) (Flashing) Cause Solution Outlet temperature sensor not sensing expected output temperature. 1. Check that the sensor is firmly attached to the hot water pipe (see Fig. 70, page 55). 2. Clean inlet filter screen and clear any debris out of shower heads, faucet aerators and whole house filters. 3. Check venting specifications are met. Long vent lengths, venting with more than three elbows, blocked vent or combination venting may cause this failure. 4.
Problem solving Display Cause Solution Over-temperature detected by outlet temperature sensor on hot water pipe. Temperature > 185°F 1. Check that the sensor is firmly attached to the vertical section of the hot water pipe (see Fig. 70, page 55). 2. Check red wire connections at outlet temperature sensor. Clean terminals with an eraser. If badly corroded, replace sensor and wire harness. Check sensor resistance (see Fig. 60, page 46. 3. Clean inlet filter screen per chapter 6.
Problem solving Display Cause Solution No flame ionization detected with water flow. 1. Verify that all manual gas shut off valves are open. 2. Check gas type, see Fig. 2, page 6. 3. Reset error code and open a water tap to cycle the heater in an effort to purge air on new installations. Cycling hot water tap on and off multiple times may be necessary. If heater still faults with EA error code, have a licensed gas technician properly purge air out of the gas line leading to the water heater. 4.
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 6720608542-04.1AL 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 temperature sensor 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
GWH 2700 ES Functional scheme 11 GWH 2700 ES Functional scheme Fig.
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 13 15 9 17 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 Fig.
Interior components diagram and parts list 12.2.6 Group 6 4 8 5 6 7 9 10 11 3 2 1 14 15 16 12 13 6720902978.AA JF Fig. 71 Components Diagram Item Description Reference Item Description Reference 1 Control unit 8 707 207 257 9 Electrode cables 8 704 401 346 1 904 521 342 10 Flue gas limiter 8 700 400 032 Cascading kit (optional) 7 709 003 617 7 709 003 665 2 Fuse T2.5A 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.
Limited Warranty 14 Limited Warranty General Service Labor Costs Aquastar water heaters are warranted by the Manufacturer (BOSCH) through Bosch Thermotechnology Corp.. Bosch thermotechnology corporation 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.
Limited Warranty 6 720 608 542 59
6720608542 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 ________________________________________