Worcester Bosch
Worcester Bosch Adapter (3-Way Valve) 8737604400
Worcester Bosch 3-way valve adapter (part 8737604400) for Greenstar 1000 and 2000 series appliances.
At a glance
- Also known as 1038431
£22.25
£18.54 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 adapter for the 3-way valve, part number 8737604400, is a component used in the diverter valve assembly of Worcester Greenstar 1000 and 2000 series appliances. It forms part of the 3-way valve arrangement that directs water between the heating circuit and the hot water circuit. This part is specific to the Worcester Bosch models listed below.
Signs this part needs replacing
- Water leaking from the 3-way valve or adapter area
- Heating or hot water not switching correctly, such as radiators heating when only hot water is demanded
- Visible corrosion, scale or cracking on the adapter
- Diverter valve fault codes or lockout on the appliance
- Reduced hot water performance or no hot water
Before you order
- Confirm your appliance model against the fit list above.
- Check the part number on the existing component matches 8737604400.
- Isolate the appliance and drain down as required before fitting.
- If unsure, consult the manufacturer's parts list for your model.
Compliance
| Alternative numbers | 1038431 |
|---|
| 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 | — | — | — |
Showing 10 of 12 compatible appliances.
Documents & drawings
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