18 | Maintenance (must be carried out only by qualified technicians)
Maintenance (must be carried out only by qualified technicians)
To ensure that gas consumption and the environmental
load (pollution, etc.) remain as negligible as possible
over a longer period of time, we recommend that you
assure to have the appliance maintained on an annual
basis (inspection) or if necessary (maintenance).
These jobs can only be done by a Bosch Technical
B Always turn off the gas cock before
carrying out any work on components
which carry gas.
CAUTION: Leaking water may damage the
B Always empty the system before
disassembly of any hydraulic system part.
B Only use original spare parts.
B Order the spare parts according to the spare parts
catalogue for the heater.
B Replace the joints and removed O-rings with new
B Only the following lubricants must be used:
– Hydraulic part: Unisilikon L 641 (8 709 918 413)
– Threaded joints: HFt 1 v 5 (8 709 918 010).
Periodic maintenance work
B Check the operation of all safety, adjustment and
B Check the heat exchanger is clean.
B In case of dirt:
– Remove the heat exchanger and take out the
– Clean the chamber with a powerful jet of water.
B If dirt persists: Soak the plates in hot water with
detergent and clean thoroughly.
B If necessary: De-lime the interior of the heat
exchanger and the connection pipes.
B Install the heat exchanger using new joints.
B Install the limiter on the support.
B Check the burner annually and clean it if necessary.
6 720 648 592 (2011/06)
B If it is very dirty (grease, soot): Remove the burner,
soak it in hot water with detergent and clean it
B Replace the water filter installed in the water valve
Is forbidden to start up the appliance
without water filter correctly assembled.
Burner and pilot injector
B Remove and clean the pilot burner.
B Remove and clean the pilot injector.
Startup after maintenance work
B Tighten all connections once more.
B Read chapter 3 "Use" and chapter 6 "Adjustments".
Flue gas safety device
The flue gas safety device must not under
any circumstances be switched off,
simulated or replaced by any other
Operation and safety precautions
The flue gas safety device checks the effectiveness of
flue gas extraction by the flue. If it is inadequate, the
appliance switches off automatically so that the
combustion fumes do not escape into the room in which
the appliance has been installed. The flue gas safety
device resets after a cooling-down period.
If the appliance shuts down while in operation:
B ventilate the room.
B Wait about 10 minutes then restart the appliance.
If the problem recurs, call an engineer.
The user must never make any
modifications to the flue gas safety device.
If faults occur on the flue gas safety device, proceed as
B Undo flue gas safety device fixing screw.
B Loosen temperature limiters connectors.