Worcester Bosch Greenstar 4000 Combi fault 2966
Flow temperature rise in heat exchanger too rapid
Gas boilerWhat it means
Rate of temperature rise in the heat exchanger detected as too rapid, indicating insufficient water flow.
Likely causes
- No water flow because CH system is closed
- No water flow because pump is not operating correctly
Where to start
- Check pump is operating freely check voltage to pump
- Check the isolation valves
- Check for air locks in the system, purge if required
The full answer, free
- How to put it right, step by step
- The manual page for this fault (page 78), right under the answer
Safety: Isolate gas and power before you open the case. If you have been into the gas side, do a tightness test, and a combustion and flue check before you hand back. Gas Safe (UK) or RGI (Ireland) work only.
From the Worcester Bosch manual for the Greenstar 4000 Combi. Check the model on the data plate before you order parts.
Other Worcester Bosch Greenstar 4000 Combi fault codes
- 1013Max. combustion point reached (the maximum burner time is reached)
- 1021Cylinder charging or hot water temperature sensor faulty
- 1037Outside temp. sensor faulty - heating backup operation active
- 1065System pressure sensor faulty or not connected
- 1068Outside temp. sensor or lambda probe faulty
- 1073Short-circuit at flow temp. sensor
- 1074No signal from flow temperature sensor
- 1075Heat exchanger temp sensor short circuit
- 1076Heat exchanger temp sensor disconnected
- 2085Internal fault
- 214Fan shut down during safety time
- 224Maximal flue gas thermostat or heat exchanger maximal thermostat has activated (blocking)
- 228Flame signal without flame present
- 234Gas valve electrical fault
- 235Conflicting versions of boiler electr. and boiler identification
- 238Boiler electronics faulty
- 242Boiler electr. system fault
- 245System fault boiler electronics / basic controller
- 249System fault boiler electronics / basic controller
- 250System fault boiler electronics / basic controller
- 251System fault boiler electronics / basic controller
- 252System fault boiler electronics / basic controller
- 253System fault boiler electronics / basic controller
- 254System fault boiler electronics / basic controller