Filter
Top Products
30
221834B
Diagram 13.1
Does the burner
remain alight ?
Isolate supply
Check continuity
between 4 and 1 on
High/Low switch.
Switch ok ?
Replace
High/Low
switch
NO
YES
2
Replace gas valve
YES
NO
NO
YES
NO
NO
Turn High/Low switch to
“High”.
Check and adjust “High”
gas pressure
(see data tables)
Is gas pressure OK?
Adjust gas
pressure
Does “High” neon light ?
Is condense drain
blocked, repair.
Does burner remain
alight ?
Is the low gas pressure
setting correct (see Data
Tables) at the test point
on the gas valve ?
NO
YES
3
YES
YES
YES
NO
Boiler satisfactory
Is the low gas pressure setting
correct (see data tables)?
Adjust as necessary.
Does burner remain alight?
Will burner remain alight if gas
pressure is temporarily
increased?
NO
Faulty injector - Replace
(Reset pressure)
YES
Faulty PCB flame detection -
Replace PCB
(Reset pressure)
PM5
13 Fault Finding