Worcester Bosch
Worcester Bosch Expansion Vessel 8737604235
Expansion vessel 8737604235 for Worcester Bosch Greenstar 1000 Series and Gr1000W 24 C and 30 C appliances.
At a glance
- Part type: Expansion vessel
- Appliance family: Greenstar 1000 Series
- Also known as 1038309
£100.30
£83.58 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 expansion vessel, part 8737604235, is the pressure-absorbing vessel fitted in the heating circuit of Greenstar 1000 Series appliances. It takes up the increase in water volume as the system heats, limiting the resulting rise in system pressure. It is used on the Gr1000W 24 C and Gr1000W 30 C models.
Signs this part needs replacing
- System pressure climbs sharply as the boiler heats and drops again once it cools.
- Water discharging from the pressure relief valve, often with a high reading on the pressure gauge.
- Repeated topping up of system pressure, or the boiler locking out on low pressure.
- No air pressure felt at the vessel charge valve when checked with a gauge.
- Water escaping from the charge valve when it is depressed.
Before you order
- Confirm the appliance model and GC number against the fit list above.
- Check the part number on the existing vessel or against the manufacturer's parts list for your appliance.
- Confirm the vessel is the cause of the pressure fault by checking the charge pressure and the pressure relief valve first.
Compliance
| Alternative numbers | 1038309 |
|---|
| 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 GR1000W 24 C NG | — | — | — | |
| WORCESTER GREENSTAR GR1000W 30 C NG | — | — | — |
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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