Worcester Greenstar 30 Si Compact LPG Boiler Fault Codes

LOCKING ERRORS
 Fault Code Cause Code Description

Reset Type

Possible Cause
9A 362 HCM (Heat Control Module)

Reset button

Incorrect HCM fitted
9U 233 HCM (Heat Control Module)

Reset button

Problem with the code plug (faulty or not connected)
b7 257 Internal error

 

Replace control board.
C6

215

216

Fan problem

Fan problem

Reset button

Reset button

Fan running too fast

Fan running too slow

C7

214

217

Fan problem

No airflow after a defined period of time

Reset button

Reset button

Fan not running

Fan not running or airflow blocked

D1

240

241

286

Return sensor error

Return sensor error

Return temperature too high

Reset button

Reset button

Reset button

Sensor wet or damaged (the boiler will block for 300 seconds before this condition).

Sensor disconnected or damaged (the boiler will block for 300 seconds before this condition).

Boiler overheat

E2

222

223

Flow sensor short circuit

Flow sensor short circuit

Reset button

Reset button

Flow sensor shorted or damaged.

Flow sensor disconnected or damaged.

E5

218

332

Flow temperature too high

Primary flow sensor has exceeded 110°C

Reset button

Reset button

Primary flow sensor overheated

Primary flow sensor overheated

E9

219

220

221

224

Safety sensor temperature too high

Safety sensor short circuit

Safety sensor open circuit

Max temperature thermostat activated

Reset button

Reset button

Reset button

Reset button

The main heat exchanger has overheated. Maximum temperature 105C° 

Maximum temperature sensor on the main heat exchanger has failed. 

Maximum temperature sensor on the main heat exchanger has not been recognised. 

Flue gas thermostat overheat 

EA

227

229

234

261

No flame detected after ignition

Loss of flame signal during operation

Gas valve error

Ignition timing error

Reset button

Reset button

Reset button

Reset button

Failure of four ignition attempts. The boiler waits 30 seconds before another attempt is made.

An established flame has been extinguished. This could be caused by: • moisture in the sump, due to a blocked sump/condensate trap. • a strong wind into the flue.

Gas valve coil disconnected

Flame not established during the first 4 seconds ignition period.

F0

237-239

242-256

258

259

262

263

267

272

279

290

Internal error

 

Call Worcester, Bosch Group Technical helpline 0330 123 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.
 BLOCKING ERRORS
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

241

Return sensor short circuit

Return sensor disconnected

Wet sensor.

Blocking for 300 seconds before going to Locking error (table 32).

Blocking for 300 seconds before going to Locking error (table 32).

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

276

277

285

MAX thermostat activated

Flow temperature exceeds 95°C

Safety temperature exceeds 95°C

Return temperature exceeds 95°C

Flue gas thermostat overheat.

Primary overheat - boiler waits for temperature to reduce; if not it becomes a Locking error.

Main heat exchanger safety sensor overheat - boiler will wait for the temperature to reduce; if not it becomes a Locking error 219.

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

213

260

380

Safety or flow temperature rises too fast

Temperature difference between supply and return exceeding limit

No temperature rise after burner starts

Inlet DHW temperature higher than the DHW outlet temperature.

Air lock or reduced water content.

Air lock or reduced water content.

Sensor disconnected or no water content.

The output is blocked until the inlet temperature drops below the output temperature.