Worcester Bosch
Worcester Bosch Adapter (Return CH) 8737604398
Return central heating adapter for Worcester Bosch Greenstar 1000 and 2000 series boilers, part number 8737604398.
At a glance
- Part type: Return central heating adapter
- Also known as 1038423
£26.70
£22.25 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 8737604398 is a return central heating adapter. It is designed for use with Worcester Bosch Greenstar 1000 and 2000 series boilers. The adapter provides a secure connection point on the central heating return circuit.
Signs this part needs replacing
- Visible water weeping or drips at the return connection
- Corrosion or mineral scale on the adapter body
- Loss of system pressure requiring frequent top-ups
- Difficulty achieving a watertight seal when refitting
- Discolouration or heat damage around the adapter
Before you order
- Confirm your boiler model matches one listed in the Fits section
- Check the part number 8737604398 against your existing component
- Ensure the system is fully isolated and depressurised before removal
- Verify whether your appliance uses natural gas or LPG, as applicable
Compliance
| Alternative numbers | 1038423 |
|---|
| 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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