Worcester Bosch
Worcester Bosch Pressure Relief Valve 8737604406
Pressure relief valve for Worcester Bosch Greenstar 1000 and 2000 series boilers, part number 8737604406.
At a glance
- Also known as 1038425
£11.30
£9.42 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 8737604406 is a pressure relief valve used on Greenstar 1000 and 2000 series boilers. It discharges excess system pressure to protect the boiler and the heating circuit. The valve is a serviceable component within the appliance.
Signs this part needs replacing
- Water discharging from the pressure relief pipework when the system is cold
- Boiler pressure dropping repeatedly and needing regular topping up
- Visible leak, staining or scale around the valve body
- System pressure rising excessively as the boiler heats up
- Valve failing to reseat and continuing to pass water after operating
Before you order
- Confirm your boiler model and GC number against the fit list above
- Check the part number on the existing valve matches 8737604406
- If pressure loss continues after replacement, check the expansion vessel charge and system pressure
- Boiler hydraulic work should be carried out by a competent heating engineer
Compliance
| Alternative numbers | 1038425 |
|---|
| 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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