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LOW NOX INSTANTANEOUS GAS WATER HEATER ROOM SEALED FAN ASSISTED / PRESSURIZED GAS WATER HEATER FOR INDOOR INSTALLATION TRAINING AND SERVICE INFORMATION FOR AFTER SALES This document is restricted to exclusive use by the official service partners. Each country should adapt the manual and its contents to the available range. Page 1 from 45 6 720 887 546 “SM FP_ErP LPP/MPP Europe 2018/05 en”...
WD 8/11 AME 23/31 WTD 12/15/18-3 AME 23/31 WTD 12/15/18-4 AME 23/31 Bosch: T – Instantaneous gas water heater T 2400 – Fixed power with electronic ignition and power steps T 5600 – Thermostatic control (variable power through electronic control) T 5700 –...
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Hydraulic & Gas Connections (supplied together with set of documents) with installation manual for each destination market are the original accessories and must be used by installer (see manual to check scope of delivery. Remote control Possible wired connection to both indoor (optional accessory) and outdoor versions (included in packaging).
Pict. 3 – Anti-Freeze Kit in appliance Activation Deactivation ≤ 4ºC ≥ 15ºC sensor sensor Table 1 – Anti-freeze activation conditions 3. Installation The installation manual of each product must be checked and used by the installer in order to optimize and leave the appliance in correct operation conditions. 3.1 Appliance fixation on the wall Requisite Confirmation...
3.2 Water connections Requisite Observations Confirmation Water pipes were cleaned before connected to the appliance? Leakage test was done successfully? Inlet water filter was checked and is cleaned, ensuring the necessary water flow? Accessories for water connections are adequate? Water pressure and flow are - Nominal pressure: 1- 4 bar according to the appliance - Minimum pressure: 0,15 bar...
Pict. 5 – Wall distance in mm required in horizontal termination Pict. 6 – Example of wall terminations in 80/110 and 60/100 type 3.5 Appliance performance Measure water flow and temperature increase to check temperature and instantaneous water flow, assuring correct operation of the appliance. Pict.
4. Components Overview [1] Fan [11] Transformer [2] Temperature Limiter [12] Control Unit [3] Heat Exchanger [13] Ignition / Ionization Electrode [4] Burner [14] Display [5] Gas manifold [15] Power switch [6] Gas valve [16] Flow sensor [7] Outlet NTC [17] Flow rate control [8] Hot water [18] Cold water...
[1] Temperature limiter [11] Heat Exchanger [2] Thermo-fuse [12] HMI [3] Burner [13] Control Unit [4] Gas manifold [14] Inlet Temperature sensor [5] Gas valve [15] Flow sensor [6] Fan [16] Cold water [7] Gas pipe [17] Flow rate control [8] Outlet Temperature sensor [18] Gas inlet [9] Hot water...
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Pict.10 – Control Panel HMI Overview WD-T2400 / T5600-T5700 On / Off button The main switch is assembled on the PCB and disconnects the unit so no voltage at components is present although anti-freeze kit keeps active due to temperatures checks even in Off mode. Menu Button - Used to Enter in service mode to access service parameters which can be used by the user, installer, technician...
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Indicative Value (in %) Power bar indicator: Note: each segment of the bar Indication of the current represents 10% of power from 0 operation power to maximum power in kW Flame indication: Symbol displayed when ionization is detected - flame Indication of flame in the presence burner...
4.2 Heat cell with burner pipes The heat cell includes the copper heat exchanger and the burner with flame visualization window, ignition electrode and ionization electrode and the gas manifold for the burner. Pict.11 – Burner and gas valve view (example from LPP / MPP) Primary air plate In the burner there is a primary air plate assembled between the gas manifold with injectors and the burner itself in order to ensure the correct mixture of air and gas...
4.3 Gas manifold The gas manifold is a gas distribution pipe with 2 types of injectors as in this burner there are two distinct primary flames with different air/fuel ratios and during whole burning process flue temperature is kept low reducing the emission of NOX assured by lean combustion and the mandatory flame stability ensured by rich flame Pict.
4.4 Fan The control unit monitories the primary air flow to the burner by varying the fan motor power supply voltage (DC), ensuring a correct variable speed during the operation according to the output needed in MPP range while in LPP the fan have a fixed speed due to the unit be fix power version.
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The gas valve is composed by other solenoids identified as safety valves (SV + SV1 + SV2) releasing the modulated gas to and from the solenoid gas valve. The safety valve (SV) is the first main safety element that releases gas to the burner and the safety valves 1 (SV1) and 2 (SV2) are the second safety level elements, that release gas to the first and second burner segments, respectively, acting as safety and segmentation valves.
The LPP unit as a fixed power version, allows through the power selector to switch manually between power level 1 (right side of burner ON = SV1) to power level 2 (left side of burner ON = SV2) to power level 3 (both sides ON = SV1 + SV2). Pict.19 –...
Pict.21 – Temperature limiter (activation at 85ºC) The thermal fuse is located around the heat exchanger and for protection is insulated, nevertheless is composed by 4 specific fuses that melt at 192 ºC in the event of an overheating. Pict.22 – Thermal Fuse with / without insulation Pict.23 –...
Pict.24 – Inlet flow restrictor with filter 4.8 Water temperature sensors The outlet and inlet water temperature is measured by a 8.5 kΩ NTC (outlet) and 50 kΩ NTC (inlet). Both NTC measures temperature and are connected to different cable colors and connectors in the control unit.
4.10 Water Flow Sensor Water flow is measured by a turbine flow sensor that is fed by a DC signal of 5 V, and gives a proportional feedback to the measured water flow. Flow rate to operate the appliance: 2.8 l/min Flow rate to shut off the appliance: 2.4 l/min Water flow characteristic curve formula:...
4.11 Ignition electrode Spark generation is started immediately before opening the gas valve, and stopped when ionization is sensed. Pict.28 – Ignition electrode (left MPP 12 l / right MPP 15/17 l) In order to prevent harder ignition processes and be sure of conditions of gas supply and burner stability, following situation is verified during the so called safety time period.
Ignition Sequence Safety Time of 31 sec Attempt Purge Period Attempt Purge Period Attempt Pos Purge (5 sec) (3 sec) (5 sec) (3 sec) (5 sec) (10 sec) and last Ignition Sequence Safety Time of 41 sec EA Error Attempt Purge Period Attempt Purge Period...
Pict.30 – Ignition electrodes position on the burner 5. Working Principle / Electric Measurements Water Flow Detection and solar mode operation Solar mode Operation Water Flow Calculation procedure Burner On Burner Off WF = Power – T < 60ºC ≥ T –...
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Connection to Operation Action the control Result unit Main Switch in control unit Input Electrical plug connected Input 230 V Standby Thermostat (temperature limiter) (Inputs Signals Input and Thermal fuse with continuity must be within Contact closed expected limits) Ionization reading Input 0 µA Ohm Value inside...
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“E1” warning code must be shown blinking with a frequency of 2Hz, so the user is aware that the water heater has automatically decreased power Overview of ECU (electronic control unit) 1- Flame detection 10- Water flow sensor 2- Ignition needle 11- Water inlet temperature sensor 3- Power plug 12- Water outlet temperature sensor...
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Overview of ECU (electronic control unit) 1- Ionization electrode (Flame detection) 10- APS (air pressure switch) 2- Ignition electrode 11- Segment valve B 3- Transformer 12- Segment valve A 4- Power supply 13- Gas valve solenoid 5- Fan 14- Safety solenoid valve 6- Water flow sensor 15- Temperature limiter (thermostat) 7- Water inlet temperature sensor...
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Part Name Wire color Value Remarks Red-Black GND 5 VDC Input Power from PCB Water flow ≈ 2.4 VDC Start-up: ≥ 2.8l/min sensor Yellow-Black GND Shut-off: ≤ 2.4/min Pulse Check the water flow character frequency Hz formula above, and calculate the frequency correspondent to different water flow.
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~0-12VDC LPP type gas valve Polarity must match in the solenoid Current =0-160mA Resistance: 80Ω Main valve Yellow-black Remain open the valve: MPP type safety valve 14 VDC Close the valve:0VDC Resistance: 115Ω Blue-Black Remain open the valve: LPP type safety valve 16-18 VDC Close the valve: 0VDC Resistance:106.5Ω...
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Air temperature sensor resistance value: Table 11 – NTC resistance values for Air Box NTC (Temperature Index table) Page 28 from 45 6 720 887 546 “SM FP_ErP LPP-MPP Europe 2018/05 en”...
34.49 6.093 1.547 32.93 5.875 1.502 31.43 5.666 1.460 30.03 5.466 1.416 28.68 5.275 1.378 27.40 5.090 1.339 26.19 4.913 1.302 25.04 4.742 1.265 23.95 4.581 1.230 22.92 4.424 1.196 Table 13 – NTC resistance values for Outlet Water NTC (Temperature Index table) In order to ensure a correct start up of the appliance and a correct function after any intervention on the appliance, the installation manual must be read and instructions and main functions must be explained to the end user.
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Pict.35 – Main parameters configuration in MPP for user level 08 = 8l Outlet temperature 11 = 11l Normal Mode Appliance capacity Enter Menu Ignition Burner Pressure P1 (level 1 – right side) Min Burner Pressure P2 (level 2 – left side) Intermed Burner Pressure P3 (level 3 –...
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Purge Mode Set point See next table with parameters Normal Mode Information Mode Only for certification Test Mode purposes if required: LP: min power mode HP Max power mode Settings Adjustments Appliance Capacity 12 / 15 / 17 Connectivity (Wifi) Gas Type Selection 20/30/31 Start up delay...
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Operating Cycles Operating Cycles … Data History Operating Cycles Setpoint Normal Mode Information Operating Hours Operation Data … Operating Hours Operating Hours Failure History 1F – 10F Last recent failures Inlet Temperature Outlet Temperature Water Flow Output power (%) Box air temperature Picture 38 –...
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Gas Power Adjustment Parameters The adjustment of the appliance for minimum / maximum power operation can be needed under following conditions: Gas Conversion (see correspondent manual); Gas valve / Fan Replacement; Start up of unit when need to operate with Propane (LPG models are adjusted on factory for Butane).
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Technician Level Comments Access to combustion adjustments Go to press ok and select P0 contains the fan speed Ignition Burner Pressure setting (A0) and gas power (L0) needed for ignition Adjustment of air flow without See installation manual for change gas conditions recommended setting Adjustment of gas flow without See installation manual for...
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Values of A0 (in P0), A1 (in P1) or A2 (in P2) are made to increase / decrease fan speed according info in the manual where a recommended value in indicated. To compare current fan speed with unit in operation with value in manual enter parameter and wait 5 seconds until real value be displayed before adjustment.
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Settings parameters Installer Level Technician Level Go to WIFI module to be launched Connectivity (compatible for all MPP 2) The value defined here is defined in ______ seconds and will create a delay in the startup sequence in order to allow (Note: from 0 to 60 pre-heated water to reach appliance sec)
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Sequence of Comment Value / Unit Parameters in P4 Operation Data Menu Temperature indication Temperature read by inlet Inlet water temperature sensor ºC or ºF Temperature indication Temperature read by outlet Hot water temperature sensor ºC or ºF Water flow indication Indicates water flow measured l/min by the turbine (l/min)
Purge mode Comments To start fan in order to proceed to the purge function Table 21 – P9 Purge 7. Maintenance To ensure continued efficient operation of the appliance, it is recommended that it is checked and serviced as necessary at regular intervals. The frequency of servicing will depend on the particular installation conditions and use profile, but in general, once a year should be adequate.
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Cleaning the filter For the cleaning of the filter, first loose the screw, than remove the cover that is fixed in the body of water valve. Clean the filter with water and / or air pressure and assemble it back on the water.
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Pict.43 – Heat Cell View with sealants between elements In hard water regions it may be necessary to descale the heat exchanger body, using a proper descaler. Fill the heat exchanger with the descaling solution and let it act until the solution stops bubbling.
8. Trouble Shooting Error code Error code definition Error code type Water temperature sensors defective Self-resolving If a short or open circuit is detected on both water NTC sensors the appliance will Lock. Error is resolved when the sensor open or short circuit is repaired.
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If a short or open circuit is detected on the inlet water NTC sensor, a warning is shown. Error is resolved when the sensor open or short circuit is repaired. Temperature limiter or thermal fuse opened circuit Lock out If the temperature limiter detects a temperature over 85ºC, the appliance shuts down and goes to lockout.
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Lock out Error is resolved by manual reset. If error persist replace control unit. Table 21 – Error code list Bosch, Termotecnologia S.A TT-DW/PRM-STI – International Training and Technical Support Aveiro Plant - Portugal Page 45 from 45 6 720 887 546 “SM FP_ErP LPP-MPP Europe 2018/05 en”...