Supplied By www.heating spares.co Tel. 0161 620 6677
page 11
NO
Open gas cocks
Contact the Gas
Supplier
Replace faulty bulb
Switch on bulbs
Replace light switch
Change resistor
Fire satisfactory
Change the electro
magnetic unit
Change pilot
assembly
Is
thermocouple
output
within limits ?
(9.4 - 13mV)
Is
meter pressure
correct ?
YES
NO
NO
YES
NO
Pipework
undersized or
restricted
Is
supply
pressure at
appliance
correct ?
NO
YES
YES
YES
NO
NO
NO
NO
YES
YES
YES
NO
YES
Are
gas cocks fully
open ?
Replace both
bulbs
Does one
bulb light?
Is
lead
from mains
connected ?
Is there
230V
across light
switch ?
Is there
230V across
resistor ?
Are bulbs
switched on ?
NO
NO
YES
YES
YES
YES
YES
Connect
lead
Rectify flue
Is flue
blocked causing
A.S.D. to
operate ?
YES
NO
Are
pilot flames
stable and approx
20mm long ?
Does
the fire remain
alight ?
Do
both bulbs
light ?
Make good the
connection
Is
thermocouple
connection
sound ?
NO
Change pilot
assembly
Is
thermocouple
tip
sound ?
NO
Clean
thermocouple tip
Is
thermocouple
tip
clean ?
NO
