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Worcester Bosch Greenstar Heatslave II External Oil Combi Boiler 12/18–25/32kW
£3,835.99
Taxes included.
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30-day return policy
Pickup available at F3 Castings Way, Leafbridge, Castings Way, Lincoln
Usually ready in 24 hours
Supplied to order. Order-in boilers are usually with us in 2-4 working days. We confirm availability and the delivery or collection date when you order.
Worcester Bosch Greenstar Heatslave II External Oil Combi Boiler 12/18–25/32kW
The Greenstar Heatslave II External is Worcester Bosch's outdoor oil condensing combi in a green weatherproof, frost-protected cabinet. It frees up kitchen and utility space in off-gas homes and comes with its balanced flue kit.
Key points
- Outputs 12/18, 18/25 and 25/32kW (2022+ models)
- 950 x 640 x 770mm (H x W x D), IP45 cabinet with frost protection
- Hot water flow rates of 15, 18 and 22 (Worcester's figures by model)
- EasyControl and solar compatible; HVO conversion kits available from Worcester
- Cabinet-mounted balanced flue (rear or side); plume management up to 5m (4m on 25/32)
What's included
- 1 x Worcester Bosch Greenstar Heatslave II External oil combi in the output you select
- Flue included: balanced flue kit, flue damper, 100mm services duct, mains supply socket and utility key, as listed in Worcester's standard package
- Literature pack and ErP label
- Side flue outlets need the 90° elbow 7716190034 (not in the box)
Specification and price
Dimensions (H x W x D): 950 x 640 x 770mm. Fuel: kerosene (class C2). Minimum mains inlet pressure 1.5 / 1.2 / 1.6 bar (12/18, 18/25, 25/32).
| Model | Output (CH / DHW) | Weight | Part number | Our code | Price (inc VAT) |
|---|---|---|---|---|---|
| 12/18 | 18kW / 18kW | 151kg | 7731600263 | PLUMHEAT0427 | £3,835.99 |
| 18/25 | 25kW / 25kW | 154kg | 7731600264 | PLUMHEAT0428 | £4,055.99 |
| 25/32 | 32kW / 32kW | 158kg | 7731600265 | PLUMHEAT0429 | £4,159.99 |
Recommended add-ons
Tick these in the add-on list above Add to cart, or follow the links:
- Worcester Bosch EasyControl CT200 smart thermostat: app and smart control; in stock in Lincoln.
- Worcester Bosch Greenstar magnetic system filter: protects the system and is required for Worcester's extended guarantee.
- Worcester Bosch Comfort+ II RF programmable thermostat: wireless programmable room control.
- Oilfit plume management kit: moves the plume away from windows and boundaries.
- Stainless steel terminal guard: for terminals within reach.
- Oilfit 90° elbow: needed for side flue outlets.
Installation and guarantee
Installation must be by a Gas Safe registered engineer (oil: OFTEC registered) and commissioned with the Benchmark checklist. Manufacturer guarantees require registration after installation and annual servicing; extended guarantee terms are the manufacturer's and may require their approved filter/installer.
Oil installations also need a correctly sited tank and oil supply line with filter, isolation and a remote-sensing fire valve, to BS 5410 and Building Regulations. Worcester Bosch's current UK product page quotes up to a 7 year guarantee (2 years standard; longer terms need a Greenstar System Filter and Worcester's registration terms).
Delivery and collection
Delivered by pallet/courier (£29.99 per order) or collect free from Leafbridge, Lincoln. Order-in boilers usually 2-4 working days.
Worcester Bosch's Heatslave II External operating instructions and the ErP data sheets for each output are in the PDF downloads at the bottom of this page.
Shop the Worcester Bosch Greenstar oil range
- Greenstar Heatslave II oil combi (internal)
- Greenstar Danesmoor External regular
- Greenstar Danesmoor External System
- Greenstar Danesmoor Utility regular
- Greenstar Danesmoor Utility System
- Greenstar Utility 32/50 and 50/70 regular
Flues and accessories: plume kit · plume extension · plume 90° elbow · plume 45° elbows · terminal guard. Browse all boilers and central heating controls.
PDF Downloads
Manufacturer documents for this product.
