Worcester Bosch
Worcester Bosch Adapter (Flow Sensor) 8737604401
Flow sensor adapter for Worcester Bosch Greenstar 1000 and 2000 series boilers.
At a glance
- Also known as 1038421
£14.54
£12.12 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Worcester Bosch 8737604401 is a flow sensor adapter for Greenstar 1000 and 2000 series boilers. It is a service component used in the DHW flow sensing circuit. The adapter is fitted where the flow sensor connects to the boiler's hydraulic assembly.
Signs this part needs replacing
- Hot water demand is not recognised, so the boiler does not fire
- Intermittent or no hot water
- Flow sensor related error codes
- Water weeping or dripping from the adapter
- Limescale or debris affecting the sensor connection
Before you order
- Check your boiler model against the fit list above
- Confirm the existing part number is 8737604401
- Inspect the flow sensor and adapter for damage or scale
- Isolate the water and power supplies before fitting
Compliance
| Alternative numbers | 1038421 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| WORCESTER GREENSTAR 1000 SERIES GR1000W 24 C NG | 47-800-38 | 47-800-38 | — | — |
| WORCESTER GREENSTAR 1000 SERIES GR1000W 30 C NG | 47-800-39 | 47-800-39 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2301iW 25 C LPG | 47-800-35 | 47-800-35 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2301iW 25 C NG | 47-800-34 | 47-800-34 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2301iW 30 C LPG | 47-800-37 | 47-800-37 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2301iW 30 C NG | 47-800-36 | 47-800-36 | — | — |
| WORCESTER GREENSTAR GR1000W 24 C NG | — | — | — | |
| WORCESTER GREENSTAR GR1000W 30 C NG | — | — | — | |
| WORCESTER GREENSTAR GR2301iW 25 C LPG COMBI | — | — | — | |
| WORCESTER GREENSTAR GR2301iW 25 C NG COMBI | — | — | — |
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Documents & drawings
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