FAULT FINDING
mini HE
--- Installation & Servicing
51
Continued from page 50
of fault finding
Continued on page 52 of
fault finding
Ensure the ignition electrode position and spark gaps are correct.
Rectify or replace. Refer to frame 41.
Is the ignition burner
pressure correct? Refer
to frame 27.
no
yes
yes
yes
yes
yes
yes
no
no
no
no
no
no
yes
yes
yes
no
yes
yes
yes
no
no
no
no
no
no
no
yes
yes
yes
no
Continued on
page 53 of
fault finding
Are LED 1 and LED 3
flashing with LED 2
on, plus LED 4 on the
facia on?
Is there 230V
at pin 101
Brown on
PCB
connecting
harness at
PCB #2?
Replace
faulty PCB
#1
Repair or
replace
faulty wiring
Press reset button. Is
there 230V across the
Black and Blue gas
valve connection
during ignition?
Rectify gas supply
fault.
Is there > 17 mbar at
the gas valve inlet?
Is there
230V at
Black and
Blue at
gas valve
harness
connector
on PCB
#2?
Repair or replace faulty wiring
Is there 230V
at pin 11
Brown on
PCB
connecting
harness at
PCB #1?
Is there continuity of
overheat thermostat
wiring at PCB
connection?
Has the main overheat
thermostat operated?
(Check continuity)
Is fuse continuity O.K. on PCB #2?
Is there a burner
pressure during
ignition period?
Replace faulty PCB #2
Replace
fuse
Are the ignition
leads
disconnected
or damaged
and sparking
to earth?
Is a spark
visible at the
burner during
ignition?
Is there ignition at the
burner?
Replace faulty gas
valve
Allow boiler to cool
and press re---set
Repair or replace
damaged wiring
Adjust ignition burner
pressure
Replace
faulty
electrode
assy. Make
connection.
Rectify
faulty
connection
Are the ignition
leads correctly
connected to
PCB #2?
Replace
faulty PCB #2
Has the flue
thermostat operated?
(Press the thermostat
reset button and/or
Check continuity)
no
yes
Allow boiler to cool
and press re---set
FA
U
LT
F
IN
D
IN
G