Supplied By www.heating spares.co Tel. 0161 620 6677
58
FAULT FINDING
Ensure boiler main
ON/OFF control is set
to position "1"
Ye
s
Go to sheet C
Check electrical supply
, appliance fuses and on/of
f control
No
Is 230V
AC present across
ter
minals L and N?
Ye
s
Is 230V
AC present across
ter
minals 3 and 5?
Ye
s
Is voltage between
16-26 VDC present across
ter
minals 8 and 9?
Ye
s
Is 5 VDC present between
5V and GND test points
on electronic board?
Replace LCD display
Ye
s
No
Repair exter
nal fault
Is the continuity
across fuse F1?
Go to sheet B
Does ON/OFF knob
operate switch on
electronic board
Boiler ON/OFF control
defective,
change electronic
board
Replace switch
mechanism
No
No
No
Ye
s
Ye
s
Note 1:
For test purposes, disconnect
exter
nal controls from ter
minal
3 - 4 and replace with a bridge
between these ter
minals.
It appliance then operates, the
fault is with the exter
nal controls.
Sheet A
Is there continuity
across fuse F3?
No
No
Replace electronic
board
No
Check transfor
mer
Replace if
necessar
y
Ye
s
Does green power on
indicator glow?