53
Response FF80
- Installation
Connect leads correctly
Are the leads of the air pressure switch
connected to 'COM' and 'N/C' (or 1 and 3)
on the switch ?
Check all components controlling
PCB 38 (thermistors, switches, panel
controls).
If no fault found, check PCB 38 by
substitution
YES
YES
Is there Live on the other end of that
wire, at the pressure switch ?
Check lead
Remove the boiler inner sealing cover.
Does the switch now have Live on both
wires ?
YES
Is there Live on the pressure switch terminal 1,
connected by a brown wire to PCB 37 ?
YES
Is there Live on the other end of the wire
(i.e. at the supply connector of PCB 37) ?
YES
NO
Check lead.
Find bad connection
or renew lead
YES
NO
Change
pressure
switch
Check for
obstructed air duct
or terminal grille
NO
NO
NO
NO
Note.
When panels are removed for service, live parts are exposed so caution should be exercised when fault-finding.
Return to
main menu
FAULT FINDING
83 Fan runs but no power on PCB 37.
F
AUL
T FINDING
When the fan runs, is there a Live
outgoing feed at PCB 38, on the terminal
connected by a brown wire to terminal 3
on the air pressure switch.