Indoor model temperature modulated with electronic ignition suitable for heating potable water only (56 pages)
Summary of Contents for Bosch Optiflow Professional GWH12
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6720808879-00.1V Room sealed gas continuous flow water heaters Optiflow Professional GWH12/16/20 1 CTD E23/31 F5 L Installation Manual Read installation manual prior to installation of this appliance! Read user manual before putting this unit in operation! Observe the warnings in the manuals! The installation location must meet the requirements for sufficient ventilation! Installation by an authorised person only!
This symbol indicates important information responsibility of the property owner. where there is no risk to people or property. ▶ Use only genuine Bosch spare parts. Explosive and highly flammable material Additional symbols ▶ Do not store or use flammable material (paper, spray cans, solvents, paints, etc) near the heater.
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4 | Key to symbols and safety instructions • Ensuring the appliance performs to the specifications All gas appliances require adequate air intake stated on the rating label. to ensure correct combustion. Insects and • Demonstrating the operation of the appliance to the dirt ingress may affect combustion causing customer before leaving.
Product details | 5 • Appliance documentation Safety of electrical appliances for domestic use and similar purposes Rating plate The following requirements apply in accordance with EN The rating plate is located on the outside of the appliance, on 60335-1 in order to prevent hazards from occurring when the bottom.
Product details | 7 Appliance layout Fig. 2 [1] Heat exchanger [13] Ignition electrode [2] Flame sensor rod [14] Burner pressure test point [3] Burner [15] Water flow sensor and Water valve [4] Air pressure test point [16] Electronic control unit [5] Fan [17] Cold water temperature sensor [6] Air temperature sensor...
8 | Product details Electrical wiring diagram Fig. 3 Electrical diagram [1] Flame sensor rod [9] Segmentation electrovalve 2 (gas) [2] Fan [10] Safety electrovalve (gas) [3] Ignition electrode [11] Thermal fuse [4] Power supply [12] Water flow sensor [5] Connection for frost protection [13] Air temperature sensor [6] Connection for remote control [14] Hot water temperature sensor...
Product details | 9 2.10 Specification Technical features Units GWH12 GWH16 GWH20 Performance Nominal Gas Consumption MJ/h 90.0 120.2 149.0 Minimum gas consumption MJ/h 11.9 18.0 18.0 Efficiency at 100% of nominal load 82.4 82.4 82.4 Gas supply data Gas supply pressure (flowing) Natural gas (when operating) 1.13 1.13...
▶ Add any flue lengths, bends, or condensate traps required may cause combustion gases to leak for your configuration. through the appliance installation ▶ Place your order using the Bosch part numbers shown compartment and may result in personal below. injury or death.
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6720809968-04.3V Fig. 4 [A] Flue pipe length [B] Lowest average inlet air temperature Bosch 4000S flue components All 4000S coaxial flue components have an internal pipe diameter of 60 mm and an external pipe diameter of 100 mm. Optiflow Professional...
12 | Regulations 2.11.2 Vertical installation Installation (only by an authorised Maximum lengths (Lmax) technicians) Lmax Concentric pipes DANGER: Explosion! GWH12 12 m ▶ Always shut off the gas valve before GWH16 carrying out work on gas pipes. GWH20 10 m The appliance installation, electrical Table 7 connection, gas connection, connection of...
Installation (only by an authorised technicians) | 13 Choice of installation site 4.2.1 Regulations concerning the installation site ▶ The water heater may not be installed over a heat source. ▶ Comply with the minimum installation clearances indicated in fig. 5 and table 10. ▶...
14 | Installation (only by an authorised technicians) Installing the appliance Item Min.clea- rance (mm) NOTICE: The appliance may be damaged if A Below eaves, balconies and other dirt is allowed to enter via the gas or water projections connections. B From the ground, above a balcony or other ▶...
Display will show “E”. ▶ Press until the display shows “AS”. Flue configuration ▶ Press the button Bosch 4000S supplied flue must be used with these Display will show “1”. appliances. ▶ Press the button and select the altitude of the Cutting coaxial flue to length installation site according with table below.
If the power cable is damaged, it must be The maximum temperature is preset to 55 °C. If required it can replaced with a Bosch supplied spare part. be increased to 60 °C or 70 °C. ▶ Enter the Service function (section 5.2).
Regulating the gas (only for authorised technicians) | 17 Service function ▶ Press the button for 3 seconds. The value flashes to confirm the new setpoint limit. Accessing the service function Calibration example ▶ Press and hold down at the same time ,and for 3 seconds.
18 | Regulating the gas (only for authorised technicians) ▶ Loosen the test point screw of the air pressure test ▶ Press for 3 seconds. point.[A] The displayed value flashes as a sign of confirmation. ▶ Connect the negative "-" side of the pressure gauge to the ▶...
Factory default settings ▶ Enter the service mode by pressing and holding down the ▶ Your appliance should only be attended to by a Bosch , and buttons simultaneously for 3 service technician. To locate your nearest service provider, seconds (section 5.2).
20 | Maintenance (only by authorised service technician) Periodic maintenance Replacement of the fuse (electronic control unit) Functional check ▶ Loosen the fixing screw of the electronic control unit ▶ Check the correct operation of all the safety, regulation and ▶...
Troubleshooting | 21 Troubleshooting Fitting, maintenance and repair must only be carried out by authorised technicians. The following table describes the possible solutions. Display Description Possible solution Cold and hot water temperature sensor damaged. ▶ Check temperature sensor and associated connections.
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22 | Troubleshooting Display Description Possible solution Air temperature sensor detects overheating (leaking ▶ Switch off at the power point and remove combustion products inside the combustion the plug from the electrical socket. chamber). ▶ Do not try to Restart the appliance. ▶...
Environmental considerations Water quality Environmental protection is a fundamental corporate strategy All Bosch water heating appliances are constructed from high of the Bosch Group. quality materials and components and all are certified for The quality of our products, their efficiency and environmental...
1. Warranty of the hot water unit. Bosch offers, at its option, to repair or exchange this Bosch hot water unit or the relevant part listed in clause 2 below at no 4. Warranty conditions charge, if it becomes faulty or defective in manufacture or (a) Proof of purchase may be required.
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Purpose. A customer can object at any time to the use of their personal information for the Purpose. Bosch will cease to use a customer's personal information accordingly if an objection is made.