Fault finding and diagnosis
67
Greenstar 8000 Style – 6720883855 (2019/01)
10
Fault finding and diagnosis
This fault finding information is for guidance only. Worcester cannot be
held responsible for costs incurred by persons not deemed to be
competent.
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).
Basic checks
• Ensure that there is 230V power supply and the polarity is correct to
the appliance.
• Ensure that the appliance settings and functionality is correct.
• Ensure the CH/DHW programmer/timer is functioning.
• Ensure the room thermostat is functioning.
• Ensure the cylinder thermostat (if fitted) is functioning.
• Ensure the cold water mains is turned on?
• Ensure the primary system has adequate pressure/system content
for the system type.
• Ensure there is gas to the appliance?
– Are other gas appliances working, gas cooker/hob for example?
– Has the credit run out on the gas pre-payment meter?
NOTICE:
On completion of the Service/Fault-Finding task which has required the
breaking and remaking of electrical connections, check:
▶ Earth continuity,
▶ Short circuit check,
▶ Polarity
▶ Resistance to earth.
10.1
Operating and fault displays
10.1.1 General information
•
Fault code
: indicates the fault.
•
Fault category
: indicates the fault and its effects.
Fault category O (operating code)
Operating codes indicate the operating conditions in normal operation.
Fault category B (blocking faults)
Blocking faults result in the heating system being shut down temporarily.
The heating system restarts automatically as soon as the blocking fault is
removed.
Fault category V (locking faults)
Locking faults result in the heating system being shut down, and the
system can only be restarted after a reset.
▶ Press the
and
keys, until
Reset
is displayed.
The appliance resumes operation.
If a fault persists:
▶ Rectify the fault according to 10.1.2 Fault code table
Fault category W (maintenance codes)
10.1.2 Fault code table
Fault
code
Fault
category
Fault text on the display, description
Remedy
200
O
Boiler in heating mode
–
201
O
Boiler in hot water mode
–
202
O
Boiler in anti-cycle mode
–
203
O
Boiler in standby, no heat energy demand
–
204
O
Current prim. water temp. higher than set
val.
–
208
O
Chimney sweep demand
–
224
V
Safety temp. limiter has tripped
1. Open the closed valve in the heating circuit.
2. Top up water until the preset pressure is reached.
3. Connect the plug correctly to the safety temperature limiter.
4. Replace the safety temperature limiter.
227
V
No flame signal after ignition
1. Open the gas isolator.
2. Change the gas installation.
3. Replace the control unit/burner control unit.
4. Replace the ignition electrode.
5. Replace the monitoring electrode.
6. Replace the ignition cable.
7. Replace the ionisation cable.
8. Replace the air/gas ratio control valve.
9. Correct the burner setting.
228
V
Flame signal without flame present
1. Replace the air/gas ratio control valve.
2. Replace the ionisation cable.
3. Replace the control unit/burner control unit.
305
O
Boiler in hot water anti-cycle mode
–
