6. To remove the display
6. To remove the display PCB, remove the two screw W4 and lift the PCB out (see Fig. 103); 7. Reassemble in reverse order; 8. To remove the main PCB disconnect all electrical connections and remove the two screws W5 (see Fig. 104); Fit the correct EEPROM supplied with the replacement PCB; 9. Reassemble in reverse order. W4 W5 Fig. 103 Fig. 104 18.4.2 Removing the fuses 1. Carry out step 18.4.1; 2. Remove the fuses “X” (see Fig. 105) 3. Reassemble in reverse order. NOTE: FUSE RATING = 2AMP FAST FUSE 18.5 Connecting the external sensor 1. Access the main PCB as in step 18.4.1; 2. Install the interface PCB supplied in the external sensot kit on the main PCB (see Fig. 106); 3. Connect the wires between the external sensor and the interface PCB* (see Fig. 106). X Fig. 105 Fig. 106 * ENSURE THAT THE WIRES FOR THE EXTERNAL SENSOR ARE CONNECTED TO THE TERMINALS INDICATED IN FIG. 110. NOTE: THE WIRES ARE NOT POLARITY SENSITIVE. IMPORTANT!! DO NOT FIT THE EXTERNAL SENSOR IN THE EVENT THAT THE BOILER IS BEING USED TO HEAT AN INDIRECT HOT WATER STORAGE CYLINDER. 52
19. Incorrect function In case of problem, or when the boiler has displayed an error code, the display flashes 2 digits. Please refer to the table below to diagnose the fault. For faults 01 and 03, A appears on the display, the boiler is locked and the reset button illuminates (28). To reset the boiler press the reset button 28. 28 Overheating lock out FAULT Fig. 107 Code Fault description A 01 Overheat lock out A 03 No flame after safety time A 36 Flue pipe too high temperature A 37 CPU fault A 39 MCU fault 1 A 40 MCU fault 2 A 41 Fan error E 02 Pump protect E 04 No flame detection E 05 Anti freezing system, pump on E 06 Anti freezing system, pump and burner on E 07 No water circulation in primary circuit E 08 No water in the primary circuit E 09 DHW sensor open circuit E 10 DHW sensor short circuit E 11 Flow sensor open circuit E 12 Flow sensor short circuit E 13 Return sensor open circuit E 14 Return sensor short circuit E 15 Outdoor sensor open circuit (if fitted) E 16 Outdoor sensor short circuit (if fitted) E 18 Flame lift E 20 Flame detect with gas valve off E 22 Fault air pressure switch E 23 Low fan speed E 29 Room thermostat open circuit E30 Room thermostat short circuit E33 Floor heating thermostat open circuit (if fitted) E 37 Communication problem with the main PCB E 38 Reset button pressed 5 times in 15 minutes 53
X