FAULT FINDING AND DIAGNOSIS
Greenstar i System Compact - 6 720 807 726 (2013/05) 65
BLOCKING ERRORS
F0 237 Internal error Call Worcester, Bosch Group Technical helpline 0844 892 3366
238
Gas valve error Reset button Leaking gas valve
239
242 - 256
258
259
262
263
267
272
279
290
Internal error Call Worcester, Bosch Group
Technical helpline 0844 892 3366
278
Sensor test failed Reset button On power up all safety sensors are checked.
Check has failed.
280
Recycle time error Reset button After the burner has stopped, the recycle mode purges gas from the
heat exchanger before attempting to burn again. The software has
3.1 seconds to intervene before the boiler goes into this fault
condition.
338
Too many short burner starts without
confirmation
Reset button There is an error where the pump is not detecting water.
F7 228 Flame error Reset button False flame. Flame detected before burner start.
328 Internal error Replace control board
FA 306 False flame error Reset button Flame detected after burner stop
FD 231 Mains power error Reset button Electrical power interruption.
FA 364 Gas valve EV2 leak test failed Reset button Gas valve leak.
Fb 365 Gas valve EV1 leak test failed Reset button Gas valve leak.
Fault
code
Cause
code Description Possible cause
A1 281 Pump stuck or running in air Little or no water in the system.
C1 264 Airflow stopped during operation Fan has stopped.
C4 273 Airflow present during last 24 hours Fan has been running continuously during the past 24 hours.
D1 240 Return sensor short circuit Wet sensor.
Blocking for 300 seconds before going to Locking error ( table 20).
241
Return sensor disconnected Blocking for 300 seconds before going to Locking error ( table 20).
D4 271 Temperature difference between flow and
safety sensors exceeds limit
The temperature of the primary flow and the safety sensor on the WB7 should
be within 15°C of each other.
E9 224 MAX thermostat activated Flue gas thermostat overheat.
276
Flow temperature exceeds 95°C Primary overheat - boiler waits for temperature to reduce; if not it becomes a
Locking error.
277
Safety temperature exceeds 95°C Main heat exchanger safety sensor overheat - boiler will wait for the
temperature to reduce; if not it becomes a Locking error 219.
285
Return temperature exceeds 95°C The boiler will stop the burn and wait to see if it cools down. If after 2 seconds
there is an increase in temperature the boiler will go to Locking error 286.
EA 227 No ionisation detected after ignition No flame is detected. The boiler will block during 4 attempts before going to
Locking fault.
EF 349 Central heating, boil detect.
Large delta T despite minimum burner.
The boiler is operating at minimum burner load and there is a greater than
18°C Flow & Return temperature difference.
No
code
212 Safety or flow temperature rises too fast Air lock or reduced water content.
213
Temperature difference between supply and
return exceeding limit
Air lock or reduced water content.
260
No temperature rise after burner starts Sensor disconnected or no water content.
380
Inlet DHW temperature higher than the DHW
outlet temperature.
The output is blocked until the inlet temperature drops below the output
temperature.
Table 21 Blocking codes
Fault codes
Cause
codes Description Reset type Possible cause
Table 20 Locking fault and cause code listing
To Next Page
Loading...
Need help?
General