Worcester Bosch
Worcester Bosch Gas Valve 848 Sigma 871860004A0
Worcester Bosch 848 Sigma gas valve (871860004A0) for Greenstar i ErP System boilers, controlling gas flow to the burner on demand.
At a glance
- Part type: Gas valve
- Also known as 1031113
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Showing prices
£171.59
£142.99 ex. VAT · VAT at 20%
In stock
Cut-off passed — dispatches next working day
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Worcester Bosch 848 Sigma gas valve (871860004A0) is a gas distribution device fitted to Greenstar i ErP System appliances. When the burner requires more gas, the control board sends a signal to the valve, which opens and releases gas through to the burner or the pilot assembly as required. It sits on the gas train between the supply and the combustion chamber, so correct operation is central to safe ignition and steady firing.
Signs this part needs replacing
- The boiler calls for heat but fails to ignite, or locks out repeatedly
- No gas reaches the burner even though the control board is signalling
- The flame lights and then drops out shortly afterwards
- Burner firing is intermittent or erratic, with unstable flame
- Debris, moisture or visible damage around the valve body or its connections
Before you order
- Check the GC number on the appliance data plate against the compatibility list to confirm the valve suits your model.
- Cross-reference alternative number 1031113 when matching against older documentation.
- Inspect the gas train seals and connections while the valve is off the appliance, and replace any that are disturbed.
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Mechanical
| Part type | Gas valve |
|---|
Compliance
| Manufacturer part number (MPN) | 871860004A0 |
|---|---|
| GC number | J04-375 |
| Barcode / EAN | 4051516200510 |
| Commodity code | 8481 80 99 00 |
| GPC classification | Valves/Fittings - Water and Gas |
| Alternative numbers | 8-718-600-04A-0, WB871860004A0, 1031113, UCP |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| WORCESTER GREENSTAR 12i ErP SYSTEM LPG | 41-406-24 | 41-406-24 | — | — |
| WORCESTER GREENSTAR 12i ErP SYSTEM NG | 41-406-23 | 41-406-23 | — | — |
| WORCESTER GREENSTAR 15i ErP SYSTEM LPG | 41-406-26 | 41-406-26 | — | — |
| WORCESTER GREENSTAR 15i ErP SYSTEM NG | 41-406-25 | 41-406-25 | — | — |
| WORCESTER GREENSTAR 18i ErP SYSTEM LPG | 41-406-28 | 41-406-28 | — | — |
| WORCESTER GREENSTAR 18i ErP SYSTEM NG | 41-406-27 | 41-406-27 | — | — |
| WORCESTER GREENSTAR 21i ErP SYSTEM LPG | 41-406-30 | 41-406-30 | — | — |
| WORCESTER GREENSTAR 21i ErP SYSTEM NG | 41-406-29 | 41-406-29 | — | — |
| WORCESTER GREENSTAR 24i ErP SYSTEM LPG | 41-406-32 | 41-406-32 | — | — |
| WORCESTER GREENSTAR 24i ErP SYSTEM NG | 41-406-31 | 41-406-31 | — | — |
Showing 10 of 60 compatible appliances.
Fitment listings are a guide, not a guarantee. Plant-room assemblies get modified on site more often than not. Send us the GC number off the data badge and a photo of the existing valve and we will confirm before anything is dispatched.
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.
manual
WORCESTER appliance manual — GREENSTAR 12i ErP SYSTEM LPG (GC 41-406-24), GREENSTAR 12i ErP SYSTEM NG (GC 41-406-23), GREENSTAR 15i ErP SYSTEM LPG (GC 41-406-26), GREENSTAR 15i ErP SYSTEM NG (GC 41-406-25), GREENSTAR 18i ErP SYSTEM LPG (GC 41-406-28), GREENSTAR 18i ErP SYSTEM NG (GC 41-406-27), GREENSTAR 21i ErP SYSTEM LPG (GC 41-406-30), GREENSTAR 21i ErP SYSTEM NG (GC 41-406-29), GREENSTAR 24i ErP SYSTEM LPG (GC 41-406-32), GREENSTAR 24i ErP SYSTEM NG (GC 41-406-31), GREENSTAR 9i ErP SYSTEM LPG (GC 41-406-22), GREENSTAR 9i ErP SYSTEM NG (GC 41-406-21)
manualmanualWORCESTER appliance manual — GREENSTAR 25SI COMPACT LPG (GC 47-406-51), GREENSTAR 25SI COMPACT NG (GC 47-406-50), GREENSTAR 30 SI COMPACT LPG (GC 47-406-53), GREENSTAR 30 SI COMPACT NG (GC 47-406-52)
manualmanualWORCESTER appliance manual — GREENSTAR 25i ErP COMBI LPG (GC 47-406-61), GREENSTAR 25i ErP COMBI NG (GC 47-406-60), GREENSTAR 30i ErP COMBI LPG (GC 47-406-63), GREENSTAR 30i ErP COMBI NG (GC 47-406-62)
manualmanualWORCESTER appliance manual — GREENSTAR 27I COMPACT SYSTEM LPG (GC 41-406-14), GREENSTAR 27I COMPACT SYSTEM NG (GC 41-406-13), GREENSTAR 30I COMPACT SYSTEM LPG (GC 41-406-16), GREENSTAR 30I COMPACT SYSTEM NG (GC 41-406-15)
manualmanualWORCESTER appliance manual — GREENSTAR 28 CDI COMPACT LPG (GC 47-406-45), GREENSTAR 28 CDI COMPACT NG (GC 47-406-44)
manualmanualWORCESTER appliance manual — GREENSTAR 32CDI COMPACT LPG (GC 47-406-47), GREENSTAR 32CDI COMPACT NG (GC 47-406-46), GREENSTAR 36CDI COMPACT LPG (GC 47-406-49), GREENSTAR 36CDI COMPACT NG (GC 47-406-48)
manualmanualWORCESTER appliance manual — GREENSTAR RI 27KW COMPACT LPG (GC 41-406-18), GREENSTAR RI 27KW COMPACT NG (GC 41-406-17), GREENSTAR Ri 30KW COMPACT LPG (GC 41-406-20), GREENSTAR Ri 30KW COMPACT NG (GC 41-406-19)
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