17
Fault Tracing
Chart Two
Does the boiler
complete self test?
(amber LED solid
illumination)
From page 16
The Heat (Green)
bar graph & fault
(Red) LED will
flash NO’s 1 to
6 or 9
NO
YES
YES
NO
NO
YES
To page 18
No preheat current
Check FBS0116
preheat resistor
assembly for 2K
OHMS
Replace FBS0116
preheat resistor
assembly
Temperature
sensor(s) fault
Replace fault sensor(s)
FBS0117 upper
FBS0118 lower
2 flashes
3 flashes
Temperature rise too
high on preheat
No water in heater
or no flow
Check for water
or flow
4 flashes
Excessive current
with relay(s) on
Faulty Triac(s)
Replace powerboard
5 flashes
Excessive current
with triac(s) on
Faulty relay(s)
Replace powerboard
6 flashes
Is temperature
differential between
flow & return greater
than 10˚C
Temperature
sensor(s) fault
9 flashes
Temperature not
stabilised before
preheat
Are flow & return
temperatures equal
Check pump
operation & valves
open
1 flash
Excessive current
flow on switch on
Triac(s) or relay(s)
faulty
Replace
powerboard
YES
Check / replace
control panel or
powerboard
Replace faulty sensor(s)
FBS0117 upper
FBS0118 lower
YES
Refer to 7 flashes
see page 18
NO
