http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html MODEL 2400E NG and 2400E 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) 2400 E NG - Natural Gas 2400 E LP - Liquefied Petroleum (LP) Gas 6 720 608 263 US (2007.
Index Index 1 W a rning 2 2 .1 2 .2 2 .3 2 .4 2.5 A p p l i a n c e d e ta i l s F eatures 2 4 0 0 E S pec ific ations (T ec hnic al data) U npac king the 2 4 0 0 E heater G eneral rules to follow for s afe operation Dimensions and Minimum installation clearances 4 4 4 5 6 7 3 3 .1 3 .2 3 .3 3 .4 3 .5 3 .6 3 .6 .1 3 . 6 .2 3 . 6 .3 3 .6 .4 3 . 6 .5 3.6.6 3 . 6 .7 3 .7 3 .8 3 .9 3 .1 0 3 .
Warning 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 undesired operation. Fig.
Appliance details 2 Appliance details 2.1 Features Parts • Touch pad interface control • High power pre-mix compact burner with low NOx emissions Capacity Maximum flow rate: 6.35 GP M (24 l/min) at a 45°F (25°C) rise. Maximum output 142,968 Btu/h (41.8 kW) • Modulating gas valve with constant gas to air ratio control Maximum input • Modulating water valve for improved comfort and temperature control. Efficiency in % 175,000 Btu/h (51.2 kW) Safety Recovery efficiency 86.
Appliance details • CO2 level set from factory, see chapter 5.4. Dimensions • Depth (in): 8 ½” (220 mm) • Width (in): 15 ¾” (400 mm) • Height (in): 23 ½” (600 mm) • Weight: 47 pounds (21 kg).
Appliance details 2.4 General rules to follow for safe operation 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. Carefully plan where you install the heater.
Appliance details 2.5 Dimensions and Minimum installation clearances Fig. 4 Dimensions 1 2 3 4 5 6 Cover On/Off switch Reset button LCD display Program button Temperature buttons Fig.
Installation instructions 3 Installation instructions 3.1 Introduction Please follow these instructions. Failure to follow instructions may result in: B Damage or injury. B Improper operation. B Loss of warranty. If you are unable to perform the tasks required to install this heater properly, please contact a locally licensed plumber or gas technician. Please contact Bosch Water Heating with any questions. 3.
Installation instructions pitch down towards termination ¼ inch for every foot of horizontal length. Single pipe method: Although it is permissible to draw combustion air from the inside, it is not the manufacturer’s recommended installation method. Always install a 3 inch elbow on the top of the combustion air inlet adaptor to prevent foreign objects from falling into the unit.
Installation instructions Fuel Gas Code. Consult a HVAC specialist if your air infiltration rate is questionable. The space must have two permanent openings, one commencing within 12 inches of the top and one commencing within 12 inches of the bottom of the enclosure.
Installation instructions 3.6 Venting Danger: Do not combination vent this appliance with any other appliance. permitted in the total vent length), or subtract 11/4 feet for every 45° elbow used. Horizontal sections of vent must pitch upwards from heater ¼" for every foot of horizontal length, to prevent the pooling of condensate, and be supported at 4 foot intervals with overhead hangers. See Table 2.
Installation instructions may result in a hazardous condition. For specific questions concerning vent material, specifications, usage or installation, contact the vent manufacturer directly. page 33. Correct the problem and then reset the heater before operating. 3.6.2 Vent connections Exhaust vent connection Vent manufacturer Contact information B Attach the flue gas exhaust accessory (8 705 504 137) to the top of the unit (position 1) using the 4 screws and gasket provided. Z-flex www.z-flex.
Installation instructions 3.6.3 Condensate drain tube requirements Exhaust collar condensate drain installation (supplied with heater) B The condensate drain tube kit must be used for all installation types. Failure to properly install condensate drain will void the warranty. B When installing the condensate drain tube kit on the exhaust collar (see diagram below), be sure to form a trap by means of a 3" (76.2 mm) loop partially filled with water.
Installation instructions a 3" or 4" pipe from the outside. See Chapter 3.5 for more direction on combustion air. B To reduce pressure differentials between the exhaust and combustion air intake, it is recommended that both terminators exit on the same plane. See Fig. 14 for an example horizontal twin pipe termination and Fig. 15 for the vertical twin pipe termination example. B Use of two 90° elbows (candy-cane) is an acceptable termination for combustion air intake from the roof. See Fig.
Installation instructions The masonry chimney may have to be tile or metal lined before the insertion of the gas vent pipe; check local codes for clarification. You may not vent any other fuel burning appliances into any free space remaining in the chimney. The vent terminator must extend at least 3 feet (0.9 m) above where the chimney meets the roofline and at least 2 feet (0.6 m) higher than any vertical wall or similar obstruction within 10 feet (3.1 m).
Installation instructions 1. Detailed instructions for the installation of the venting system or the venting system components: and 2. A complete parts list for the venting system design or venting system. (d) MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED.
Installation instructions Recommended exhaust vent terminator clearances Fig. 17 Ref.
Installation instructions 3.6.7 Exhaust vent configuration examples Supporting the exhaust vent system Fig. 18 Horizontal side wall venting installation (combustion air piping not shown) Note: Pitch venting up 1/4" per foot to termination and add additional condensate drain for vent runs longer than 5 linear feet. Note: Pitch venting down 1/4" per foot to termination for vent runs less than 5 linear feet.
Installation instructions 3.7 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 CGA B149 INSTALLATION CODES and/or local installation codes.
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 2400 E (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.
Installation instructions 3.8 Measuring gas pressure Confirm proper gas pressure upon installation. Connecting Manometer B Shut off gas supply at installer supplied shutoff valve. B Remove front cover and locate inlet gas pressure measuring point (see Fig. 24). B Loosen screw inside left test point fitting (do not remove) and connect manometer tube to test point. Remove screw completely if correct size adapter is available. Static Pressure Test Fig.
Installation instructions 3.9 Water connections or flush the lines before connecting to the water heater. Warning: This heater must be supplied with cold potable water. It is not approved for preheated water applications. See chapter 3.12 for approved recirculating application. B Full port shutoff valves should be installed on both the cold water supply and hot water outlet lines to facilitate servicing the heater (see Fig. 26).
Installation instructions 3.10 Electrical connections 2400 E 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 4 Operation instructions Fig. 28 1 2 3 4 5 6 4.1 On/Off switch Reset button Program “ “ button Increasing temperature selector Decreasing temperature selector LCD display For your safety, read before operating your water heater Warning: The front cover of this appliance must be secured and properly sealed at all times once vent pipe and water connections are made.
Operation instructions Off B To shut down the appliance move the on/off switch to the “off” position (0). 4.3 Temperature selection To select output water temperature: B Press buttons temperature. and in order to reach desired Fig. 30 If the outlet water temperature is set too high, the heater can produce temperatures that are too hot. A temperature balance shower valve will automatically mix in cold water to reduce such hot water temperature.
Operation instructions Setting the water temperature The desired temperature of the hot water can be adjusted on the front control panel of the heater. The 2400 E has an electronically controlled gas valve that modulates the burner input in response to both varying hot water flow rates and/or changes in any incoming and outgoing water temperatures. Note: selected temperature on heater’s display will blink until that temperature has been reached. Fig.
Operation instructions 4.4 B press reset button in order to return heater to normal operation. Use of optional remote control accessory Fig. 35 Reset button If the problem persists or error code will not reset, contact your installer. Fig. 32 Remote control The wireless remote control accessory and the temperature selector buttons on the front of the water heater operate identically. Contact your installer or distributor to order the remote control accessory.
Maintenance and service 5 Maintenance and service Warning: Always turn off the electrical power supply, turn off the manual gas valve and turn off the manual water control valves when servicing heater. The unit should be checked once a year by a gas technician. If repairs are needed, the repairs should be done by a gas technician 5.1 Descaling • In areas where the water supply has a high mineral content, the heat exchanger may need to be flushed with a descaling solution.
Maintenance and service 5.3 Mineral scale build-up Periodic descaling may be necessary in areas with high mineral content in the water. Scale buildup in the heat exchanger may result in lower flow rates, error codes of A7 and E9 and boiling sounds in the heat exchanger. 16.Reconnect electrical supply to unit, open water isolation valves, and return the unit to service. Descaling using a pump 1. Disconnect electrical supply from the water heater. 2.
Maintenance and service pipe (approx 1.5" inserted). Avoid air gaps between probe and measuring port as it can alter readings. CO2 level Max CO level Nat. Gas max. input P1 9.7 ± 0.3 % min. input P2 9.5 ± 0.5 % 300 ppm LP Gas max. input P1 10.7 ± 0.3 % min. input P2 10.5 ± 0.5 % 300 ppm * Final reading must be confirmed with the front cover on, CO2 levels increase when the cover is installed. Table 9 Fig. 40 Measuring port 1.
Maintenance and service Fig. 43 Adjusting P2 CO2 level 3. Verify both P1 and P2 CO2 readings are within the ranges specified in table 10. Repeat steps 1 and 2 as necesssary until CO2 values are within the specified ranges. 4. Once CO2 values are within the specified ranges, verify the CO readings on P1 do not exceed 300ppm (follow local codes). If values exceed this limit, inspect vent system and fin coils (Chapter 5.1) for blockage. D. Returning to Service: 1.
Maintenance and service 5.5 Control board diagnostics 1. Turn on/off switch on water heater to off (O) position.
Troubleshooting 6 Troubleshooting Warning: If you are unable to perform the tasks listed below, or need additional assistance please contact your original installer/licensed gas technician. 6.1 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. For best results, perform each step before proceeding to the next.
Troubleshooting 7. Cold water is mixing into the hot water lines (plumbing crossover). A plumbing crossover can unintentionally 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 feed 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.
Troubleshooting 2. Improper venting. Venting that is unsealed, the wrong material, too big in diameter or too long in run will result in unstable burner flames and noise. Ensure venting is correct and in accordance with specifications in chapter 3.6. 3. Lack of adequate combustion air. Drawing combustion air from a room area of inadequate size or improper piping of combustion air from the outside will result in unstable burner flames and noise.
Troubleshooting 6.8 Error code diagnostics Part numbers subject to change. Display Cause Solution A2 Fault in the flue gas limiter (part# 8700400032). Note: Old style overheat cutoff fuse (8700400019) has been replaced with this new limiter. 1. Check for flue gas leakage around the top and bottom seals of heat exchanger as well as the viewing window. Look for any noticeable burn marks or warping of the gaskets. If a leak is detected, seals will need replacing. 2.
Troubleshooting Display Cause Solution C1 Fan rotation too low on startup. (part# 8707204039) 1. Disconnect power supply cord. Check wire connections on back side of fan and the two large wire connectors on the control unit. Removal of lower access panel on control unit is necessary to access connectors. 2. Verify that supply voltage is 120VAC and is properly grounded. 3. Verify that venting meets specifications outlined in chapter 3.6.
Troubleshooting Display Cause Solution E1 Over-temperature detected by temperature sensor on hot water pipe. (part# 8700400015) 1. This water heater must be supplied with cold water for domestic hot water only. Do not recirculate water through this heater or supply with preheated water. 2. Check that the hot water temperature sensor is firmly attached to the horizontal section of the hot water pipe. 3. Check red wire connections at hot water temperature sensor. Clean terminals with an eraser.
Troubleshooting Display Cause Solution EA No flame ionization detected with water flow. (part# 8708107020) 1. Verify that all manual gas shut off valves are open. 2. Verify gas type (See Fig. 2) corresponds with the type of gas supplied to the heater. 3. Reset error code and open a water tap to cycle the heater in an effort to purge air from gas line (especially on new installations). Cycling hot water tap on and off multiple times may be necessary.
Troubleshooting Display Cause Solution F7 Ionization error at standby. (part# 8708107020) 1. Loose connection to the flame ionization rod. Verify that the thinner yellow wire leading from the control unit is securely connected to the set of electrodes located at the bottom right-hand side of the heat exchanger. 2. Flame ionization rod or control unit may be damaged. Contact Bosch Water Heating for further instruction. FA Gas leakage error, gas valve circuit not closing properly.
Electrical diagram 7 Electrical diagram Fig. 44 Electrical scheme 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Intlet water temperature sensor Ionization sensor Water flow sensor Flue gas limiter Temperature limiter / ECO Gas valve Fan Water valve AC Plug Ignition electrode Display PCB ON/OFF switch Fuse T 2.5A Fuse T 3.
2400 E Functional scheme 8 2400 E Functional scheme Fig.
Interior components diagram and parts list 9 Interior components diagram and parts list 9.1 Interior components Fig. 46 Components 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Cover On/Off switch Reset button LCD display Program button Temperature switches Flue gas collector Mixer Heat exchanger Observation window Inlet air duct Control unit Exhaust fan Water valve Gas valve Fig.
Interior components diagram and parts list 9.2 Components diagram Fig.
Interior components diagram and parts list 9.
Protecting the environment 10 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.
Twelve Year Limited Warranty 11 Twelve Year Limited Warranty General Service Labor Costs Aquastar water heaters are warranted by the Manufacturer (BOSCH) through BBT North America. BBT North America (BBTNA) 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.
Replacement Parts available from: BBT NORTH AMERICA Bosch Group Bosch Water Heating 340 Mad River Park Waitsfield, VT 05673 Phone 800-642-3111 Fax (802) 496-6924 www.boschhotwater.com techsupport@boschhotwater.com Recycled paper BBT Termotecnologia Portugal S.A.
