Fault Finding - Worcester GREENSTAR HIGHFLOW 440CDi Instruction Manual

Display code:
A5
A7
A8 EMS communication error
b1 Code plug not detected
b2, b3, b4, b5,
b6
b7 Burner control error
C6
D3 External temp limiter
D5 Condensate overflow
D6 Internal heat bank overflow
EA Flame not detected
E2 Primary NTC defect
E9
F0
F1
F7 Flame detected after appliance
FA Flame detected after gas shut off Check flame sense electrode and harness,
Fd Reset button pressed
CONDENSATE PUMP - OPERATING LAMPS AND FAULT CONDITIONS
Ready for operation
Fault
Pump running
Operating lamps
Green
Off
Flashing
On
On
Off
52

FAULT FINDING

BOILER - FAULTS AND CONDITIONS
Fault description Check, repair/replace as necessary
Tank NTC defect Check tank NTC sensor and leads,
measure resistance across NTC
DHW NTC defect Check DHW NTC sensor and leads,
measure resistance across NTC
Check all electrical connections,
Insert code plug correctly, test and
Data error
Fan defect Check fan, lead, and connector,
Connect terminals 8 & 9 on ST8.
Check system pressure, tank, over heat
thermostat, and pump operation
Check gas is present, ignition electrodes
and harness, flame sense electrode and
harness, and operation of gas valve.
Check primary NTC sensor and leads,
resistance across NTC should be between
OH stat tripped Check system pressure, over heat thermo-
Internal error Check all electrical connections, replace
ROM error check Check all electrical connections, replace
Check flame sense electrode and harness,
shut off and control board for signs of water
damage. Replace a s necessary
and control board for signs of water
damage. Check gas valve operation.
= Steady green light
= Red light
= Flashing green light
Cause
Red
Off Mains plug not plugged in
Power failure
Flashing Dry-run
(poss. air in pump)
Flashing Pump blocked
On Level exceeds alarm level
Flashing Pump blocked and
alarm level exceeded
(33.5kΩ- 500Ω)
(33.5kΩ- 500Ω)
replace control board.
replace as necessary.
Replace control board.
Replace control board.
replace as necessary.
See condensate pump table.
Replace as necessary.
36k to 1kΩ
stat, and pump operation.
Replace as necessary
board as necessary.
board as necessary.
Replace a s necessary
Press reset button again
FAULT FINDING
NOTE ; This fault finding information is for
guidance only. Worcester Bosch cannot be held
responsible for costs incurred by persons not
deemed to be competent.
The electronic control system for this boiler
incorporates a blue central indicator. This
normally confirms the permanent mains supply,
but, by flashing during a fault, provides a guide
to the cause as listed.
This fault finding system assumes that the
appliance has been operating normally until the
time of failure (i.e. not a first time installation
error).
Preliminary checks:
Preliminary electrical system checks are the
first electrical checks to be carried out during
a fault finding procedure.
On completion of the Service/Fault finding
task which has required the breaking and
remaking of electrical connections, check:
a) EARTH CONTINUITY
b) SHORT CIRCUIT CHECK
c) POLARITY
d) RESISTANCE TO EARTH.
Solution
Insert plug
Check mains and fuse
Pump restarts automatically
after one minute
Visual inspection of the pump inlet
in the tank and removal or
rinsing out of dirt/foreign bodies
Pressure hose / non-return valve
blocked (clean or remove kink
if applicable)
Visual inspection of the pump inlet
in the tank and removal or
rinsing out of dirt/foreign bodies
INSTALLATION & SERVICING INSTRUCTIONS
8 716 115 219c (03.2010)