Worcester Bosch Greenstar 4000 Combi fault 1074
No signal from flow temperature sensor
Gas boilerWhat it means
No signal detected from the flow temperature sensor, indicating an open circuit or disconnection.
Likely causes
- Sensor disconnected
- Faulty sensor
- Damaged harness
- Faulty PCB
Where to start
- Check the flow temperature sensor plug is connected
- Check the resistance of the flow temperature sensor
- Check the continuity of harness
The full answer, free
- 7 more checks in order
- How to put it right, step by step
- The manual page for this fault (page 76), 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
- 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
- 258System fault boiler electronics / basic controller