Worcester Bosch
Worcester Bosch Printed Circuit Board Greenstar 25Si 30Si 8748300939
At a glance
- Part type: Printed circuit board
- Appliance family: Greenstar 25Si and 30Si combi and RSF
- Also known as WB8748300939, 1015538, N0412-1
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
£111.40
£92.83 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 8748300939 is a printed circuit board (PCB) used in Greenstar 25Si and 30Si combi and RSF appliances. It is the main control board, handling ignition sequencing, fan and gas valve control, temperature regulation and the safety interlocks that keep the boiler operating within its design limits. The board also carries the connections for the appliance's sensors, display and internal wiring harness.
Signs this part needs replacing
- The boiler fails to fire, or the fan runs without the burner lighting
- No display, blank screen or unlit status indicators on the control panel
- Repeated lockouts or fault codes that clear and then return shortly after reset
- Erratic behaviour such as the boiler cycling, cutting out mid-demand or running the pump without heat
- Visible damage on the board itself, including burnt tracks, discoloured components or a blown fuse
Before you order
- Check the GC number and appliance serial plate to confirm the board matches your boiler variant, as LPG and natural gas versions are listed separately
- Compare the numbers printed on the existing board against the alternative part numbers below before ordering
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Mechanical
| Part type | Printed circuit board |
|---|---|
| Appliance family | Greenstar 25Si / 30Si |
Compliance
| Manufacturer part number (MPN) | 8748300939 |
|---|---|
| GC number | H31-408 |
| Barcode / EAN | 4062321168223 |
| Commodity code | 8537 10 00 00 |
| GPC classification | Household Boilers/Furnaces/Tank Water Heaters Replacement Parts/Accessories |
| Alternative numbers | WB8748300939, 8-716-109-540-0, 8-748-300-634-0, 1015538, N0412-1 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| WORCESTER GREENSTAR 25SI COMBI LPG | 47-311-88 | 47-311-88 | — | — |
| WORCESTER GREENSTAR 25SI COMBI NG | 47-311-84 | 47-311-84 | — | — |
| WORCESTER GREENSTAR 30 SI COMBI LPG | 47-311-89 | 47-311-89 | — | — |
| WORCESTER GREENSTAR 30 SI COMBI NG | 47-311-85 | 47-311-85 | — | — |
| WORCESTER WORCESTER GREENSTAR 25Si RSF LPG | — | — | — | |
| WORCESTER WORCESTER GREENSTAR 25Si RSF NATURAL GAS | — | — | — | |
| WORCESTER WORCESTER GREENSTAR 30Si RSF LPG | — | — | — | |
| WORCESTER WORCESTER GREENSTAR 30Si RSF NATURAL GAS | — | — | — |
Documents & drawings
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