44
xtra
-
Installation & Servicing
FAULT FINDING
FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING FAUL
T FINDING
Code
Description
Action
08
Air Pressure Switch did not close
Check flue for blockage
Check/clean burner
Check Air Pressure Switch sensing pipes
condition
Check fan speed
Check air Pressure Switch & replace if
necessary
18
Flow temperature too high
Check no air in system or boiler
Check adequate flow of water through boiler
19
Return temperature too high
Check no air in system or boiler
Check adequate flow of water through boiler
24
Return temperature > Flow temperature for excessive time
Check no air in system or boiler
Check adequate flow of water through boiler
25
Flow temperature rise too fast
Check no air in system or boiler
Check adequate flow of water through boiler
28
No tacho signal from fan
Check wiring to fan
If wiring OK replace fan
29
Incorrect tacho signal from fan
Check wiring to fan. If wiring OK replace fan.
30
Flow/return temperature differential too high
Check no air in system or boiler
Check adequate flow of water through boiler
33
Tank sensor short circuit
Check wiring
Disconnect terminals from tank sensor &
confirm short circuit using meter
Replace tank sensor
35
Flue thermistor short circuit
Check wiring
Disconnect terminals from thermistor &
confirm short circuit using meter
Replace thermistor
38
Tank sensor open circuit
If not fitted check parameter 46 settings
Check wiring
Disconnect terminals from tank sensor &
confirm open circuit using meter
Replace tank sensor
40
Flue thermistor open circuit
Check wiring
Disconnect terminals from
thermistor & confirm open circuit using meter
Replace thermistor
43
Parameter values in EEPROM values out of range
Replace control module.
52
Flue gas temperature too high
Check no air in system or boiler
Check adequate flow of water through boiler
65
Fanspeed during start not within the dead band
Check wiring to fan. If wiring OK replace fan.
109
Heat exchanger temperature too high
Check no air in system or boiler
Check adequate flow of water through boiler
116
Mains frequency deviation > 1.5Hz or processor oscillator error
If mains supply frequency OK replace control module.
118
Flame current lost during burner on
Check wiring
Check condition of ignition/detection
electrode & replace if necessary
Boiler Control Module Blocking Codes
61 TECHNICAL CHARACTERISTICS - TEMPERATURE SENSORS
The table below gives the relationship between temperature and resistance for the following sensors; flow thermistor, return
thermistor, flue thermistor, heat exchanger thermistor, outside temperature sensor and DHW tank sensor.
Temperature in
o
C
Resistance in ohm
Temperature in
o
C
Resistance in ohm
10
22,800
60
32,250
20
14,700
70
2,340
30
9,800
80
1,710
40
6,650
90
1,260
50
4,610
100
950
