Worcester Bosch
Worcester Bosch Expansion Vessel 8716122887
Expansion vessel 8716122887 for Worcester Bosch Greenstar 2000 and 4000 combi and system boilers.
At a glance
- Appliance family: Greenstar 2000 and Greenstar 4000 combi and system boilers
- Also known as 1011038
£72.59
£60.49 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 number 8716122887, is the sealed diaphragm vessel fitted to the heating circuit of Greenstar 2000 and 4000 combi and system boilers. It absorbs the increased water volume as the system heats and expands, holding circuit pressure within the range the boiler is designed to work at. The vessel is a serviceable component and is replaced when the internal diaphragm no longer holds its charge.
Signs this part needs replacing
- System pressure climbs quickly as the boiler heats up and falls again once it cools.
- The pressure relief valve discharges, with water appearing at the relief pipe outlet.
- The boiler needs frequent topping up to keep the pressure gauge in the correct band.
- The gauge reads low or zero on a cold system, or pressure swings widely between heating cycles.
Before you order
- Check the boiler model and GC number on the appliance data plate against the fit list above.
- Confirm the part number currently fitted to the appliance matches 8716122887.
- Check the system has been depressurised and drained before the vessel is removed.
Compliance
| Alternative numbers | 1011038 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| WORCESTER GREENSTAR 2000 COMBI GR2300iW 25 C LPG | 47-800-27 | 47-800-27 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2300iW 25 C NG | 47-800-26 | 47-800-26 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2300iW 30 C LPG | 47-800-29 | 47-800-29 | — | — |
| WORCESTER GREENSTAR 2000 COMBI GR2300iW 30 C NG | 47-800-28 | 47-800-28 | — | — |
| 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 4000 COMBI GR4700iW 25 C LPG | 47-800-31 | 47-800-31 | — | — |
| WORCESTER GREENSTAR 4000 COMBI GR4700iW 25 C NG | 47-800-30 | 47-800-30 | — | — |
Showing 10 of 44 compatible appliances.
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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