Worcester Bosch
Worcester Bosch Pressure Relief Valve 3 Bar 87186445660
3 bar pressure relief valve for Worcester Bosch Greenstar 2000 Combi and Gr2300IW boilers, part 87186445660.
At a glance
- Also known as 8905405
£47.09
£39.24 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 pressure relief valve 3 bar is a safety valve fitted to Worcester Bosch Greenstar 2000 Combi and Gr2300IW boiler models. It opens at its rated pressure to discharge excess water and protect the appliance and system from over-pressurisation. The supplied product name for this item is PRESSURE RELIEF VALVE 3 BAR, manufacturer part number 87186445660.
Signs this part needs replacing
- Water discharging continuously from the pressure relief discharge pipe while the boiler is running or idle.
- System pressure rising steadily during heating cycles and not settling back within the normal cold-fill range.
- Boiler pressure gauge reading high, with the valve failing to hold at its rated opening pressure.
- Repeated loss of system pressure requiring frequent manual top-ups.
- Scale, debris or corrosion visible at the valve outlet or seating area.
Before you order
- Confirm the appliance model and GC number against the boiler data plate and the fits list above.
- Check the existing valve is rated at 3 bar before ordering.
- Verify the manufacturer part number 87186445660 matches the number on the existing valve or the appliance parts list.
- Confirm the boiler is a Greenstar 2000 Combi or Gr2300IW variant, as fitment is limited to the models listed.
Compliance
| Alternative numbers | 8905405 |
|---|
| 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 GR2300iW 25 C LPG COMBI | 47-800-27 | 47-800-27 | — | — |
| WORCESTER GREENSTAR GR2300iW 25 C NG COMBI | 47-800-26 | 47-800-26 | — | — |
| WORCESTER GREENSTAR GR2300iW 30 C LPG COMBI | 47-800-29 | 47-800-29 | — | — |
| WORCESTER GREENSTAR GR2300iW 30 C NG COMBI | 47-800-28 | 47-800-28 | — | — |
Documents & drawings
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