- 29 -ENGLISHLOCK OUTShould the flame accidentally go out the control unit (21) automatically repeats a new ignition sequence. If re-ignition failsto occur within the maximum safety time (10 seconds) the burner will lock out (i.e. shut down) and the warning light on thereset button (20) will come on as will the warning light on the room thermostat shut-down device (where fitted).The burner cannot be re-ignited unless the release device is manually reset by acting on the push-button (20). If, after thesafety time has elapsed, it shuts down again the cause may be one of the following:- No fuel in tank.- Nozzle (3) faulty or dirty.- Ignition electrodes (4-5) encrusted or damaged (see positions in Fig. 13).- Photo-resistor (19) obscured- Faulty solenoid valve seal (29)- Dirty pump filter- Air infiltrates into aspiration pipes- Pipe filter dirty (if fitted).WARNING: in the event of lock-out always act exclusively on the reset button (20)and never on the burner electrical circuit. If necessary, contact a professionally qua-lified technician.MAINTENANCEWARNING: all work must only be done after first cuttingpower via the main switch and after removing the plug (38).By removing the cover (23) from the burner it is possible tocarry out the following checks and cleaning tasks.PHOTORESISTOR (19)Remove and clean the sensor carefully. Use a clean, dry cloth. When replaced make sure it is properly attached. If aBRAHMA photo-resistor is installed you must observe the 55 mm gap illustrated in fig. 12.NOZZLE (3)Remove the high voltage wires (24) on the transformer side and the photo-resistor (19), unscrew the coupling (18) and theother coupling (30) on the fuel pump. Unscrew the cover attachment screws (9) and extract the nozzle holder set (10) byrotating the cover anticlockwise. Remove the high voltage wires on the electrodes (4-5), loosen the holder lock screw (6),remove the diffuser/electrodes holder (43) and then unscrew the nozzle. To clean the nozzle thoroughly disassemble thefilter and clean the slots and the spray hole with petrol. Never use tools which might damage internal surfaces.Fig. 11Fig. 12