Worcester Bosch
Worcester Bosch Water Valve Diverter 87170021100
Worcester Bosch diverter water valve 87170021100 for Greenstar, Si/C1 Series and RD Series combi boilers, directing water to heating or hot water.
At a glance
- Part type: Water valve (diverter valve)
- Appliance family: Greenstar, Si/C1 Series, RD Series
- Also known as 1019899
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
£186.97
£155.81 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 87170021100 is a diverter valve — a directional water valve used in the hydraulic section of a combi boiler. It switches the flow of heated water between the central heating circuit and the domestic hot water circuit, so the boiler can serve either demand without mixing the two. It is built for the Greenstar, Si/C1 Series and RD Series appliance ranges.
Signs this part needs replacing
- Hot water runs cold or lukewarm while the central heating continues to work normally
- Radiators heat up when only a hot water tap is opened
- Domestic hot water temperature fluctuates or drops away during a draw-off
- Water weeping from the valve body or from the joints around it
- The valve no longer moves through its full travel, or the actuator stalls
Before you order
- Check the appliance GC number and model on the data plate against the compatibility list before ordering.
- Confirm the part number on the existing valve, and note the earlier numbers 87170021220 and DD97909062 that this valve replaces.
- Inspect the seals and O-rings on the existing assembly so any that are perished can be renewed at the same time.
- This part is fitted to a gas appliance; installation must be carried out by a Gas Safe registered engineer.
Mechanical
| Part type | Valves General, Assembly |
|---|---|
| Appliance family | Greenstar, Si/C1 Series, RD Series |
Compliance
| Manufacturer part number (MPN) | 87170021100 |
|---|---|
| GC number | E27-274 |
| Barcode / EAN | 4010009466482 |
| Commodity code | 8481 80 99 00 |
| GPC classification | Valves/Fittings - Water and Gas |
| Alternative numbers | 87170021220, DD97909062, 1019899 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| WORCESTER 25 SI RSF COMBI LPG | 47-311-50 | 47-311-50 | — | — |
| WORCESTER 25 SI RSF COMBI NG | 47-311-49 | 47-311-49 | — | — |
| WORCESTER 28 SI RSF LPG | 47-311-52 | 47-311-52 | — | — |
| WORCESTER 28 SI RSF NG | 47-311-51 | 47-311-51 | — | — |
| WORCESTER BRITISH GAS C1-FSN-GB NG COMBI | 47-311-53 | 47-311-53 | — | — |
| WORCESTER BRITISH GAS GREENSTAR CC1-FSN-GB NG 29KW COMBI | 47-108-05 | 47-108-05 | — | — |
| WORCESTER BRITISH GAS GREENSTAR GREENSTAR HE PLUS-FSN- GB28KW | 47-311-56 | 47-311-56 | — | — |
| WORCESTER BRITISH GAS GREENSTAR GREENSTAR HE-FSN-GB NG 27KW | 47-311-55 | 47-311-55 | — | — |
| WORCESTER BRITISH GAS GREENSTAR ICC2-FSN-GB NAT 30KW COND COM | 41-108-09 | 41-108-09 | — | — |
| WORCESTER BRITISH GAS GREENSTAR ICC2-FSN-GB NAT 37KW COND COM | 41-108-10 | 41-108-10 | — | — |
Showing 10 of 51 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.
WORCESTER appliance manual — 25 SI RSF COMBI LPG (GC 47-311-50), 25 SI RSF COMBI NG (GC 47-311-49), 28 SI RSF LPG (GC 47-311-52), 28 SI RSF NG (GC 47-311-51)
manualmanualWORCESTER appliance manual — BRITISH GAS C1-FSN-GB NG COMBI (GC 47-311-53)
manualmanualWORCESTER appliance manual — BRITISH GAS GREENSTAR ICC2-FSN-GB NAT 30KW COND COM (GC 41-108-09), BRITISH GAS GREENSTAR ICC2-FSN-GB NAT 37KW COND COM (GC 41-108-10)
manualmanualWORCESTER appliance manual — GREENSTAR 25 HE (GC 47-311-73), GREENSTAR 30 HE COMBI (GC 47-311-74)
manualmanualWORCESTER appliance manual — GREENSTAR 30 HE PLUS COMBI (GC 47-311-75), GREENSTAR 35 HE PLUS COMBI (GC 47-311-76), GREENSTAR HE PLUS-FSN-GB35KW (GC 47-311-57)
manualmanualWORCESTER appliance manual — GREENSTAR R25HE COMBI (GC 47-311-77), GREENSTAR R30HE COMBI (GC 47-311-78)
manualmanualWORCESTER appliance manual — GREENSTAR R30HE PLUS COMBI (GC 47-311-79), GREENSTAR R35HE PLUS COMBI (GC 47-311-80), GREENSTAR R40HE PLUS COMBI (GC 47-311-81)
manualmanualWORCESTER appliance manual — GREENSTAR RSF COMBI NG (GC 47-311-44), GREENSTAR ZWBR 11-25 A31 LPG (GC 47-311-45)
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